ZSSC3027AC6B_技术文档

ZSSC3027

Low-Power, High-Resolution

Datasheet

16-Bit Sensor Signal Conditioner

Brief Description

Benefits

•

Integrated 18-bit calibration math DSP

The ZSSC3027 is a sensor signal conditioner (SSC)

integrated circuit for high-accuracy amplification and

analog-to-digital conversion of a differential input

signal. Designed for high-resolution altimeter module

applications, the ZSSC3027 can perform offset,

span, and 1^stand 2^ndorder temperature compen-

sation of the measured signal. Developed for correc-

tion of resistive bridge sensors, it can also provide a

corrected temperature output measured with an

internal sensor.

Fully corrected signal at digital output

One-pass calibration minimizes calibration costs

No external trimming, filter, or buffering com-

ponents required

•

Highly integrated CMOS design

Excellent for low-voltage and low-power battery

applications

•

Optimized for operation in calibrated resistive

sensor modules

The measured and corrected bridge values are

provided at the digital output pins, which can be

configured as I²C™* (≤ 3.4MHz) or SPI (≤ 20MHz).

Digital compensation of signal offset, sensitivity,

temperature, and non-linearity is accomplished via

an 18-bit internal digital signal processor (DSP) run-

ning a correction algorithm. Calibration coefficients

are stored on-chip in a highly reliable, non-volatile,

multiple-time programmable (MTP) memory. Pro-

gramming the ZSSC3027 is simple via the serial

interface. The IC-internal charge pump provides the

MTP programming voltage. The interface is used for

the PC-controlled calibration procedure, which pro-

grams the set of calibration coefficients in memory.

Physical Characteristics

•

Supply voltage range: 1.7 to 3.6V

Operating mode current consumption:

930µA (typical)

•

Sleep State current: 20nA (typical)

Temperature resolution: <0.003K/LSB

Operation temperatures: –40°C to +85°C

Small die size

Delivery options: die for wafer bonding

Available Support

The ZSSC3027 provides accelerated signal process-

ing in order to support high-speed control, safety,

and real-time sensing applications. It complements

IDT’s ZSSC30x6 products.

•

ZSSC3026 Evaluation Kit can be used to

evaluate ZSSC3027 capabilities

•

Support Documentation

ZSSC3027 Application Example

Features

•

Flexible, programmable analog front-end design;

up to 16-bit scalable, charge-balancing two-

segment analog-to-digital converter (ADC)

•

Fully programmable gain amplifier accepting

sensors from 14 to 72 (linear factor)

•

Internal auto-compensated temperature sensor

Digital compensation of individual sensor offset;

1^stand 2^ndorder digital compensation of sensor

gain as well as of 1^stand 2^ndorder temperature

gain and offset drift

•

Layout optimized for stacked-die bonding for

high-density chip-on-board assembly

* I²C™ is a trademark of NXP.

** FSO = Full Scale Output.

Typical sensor elements can achieve accuracy of

better than ±0.10% FSO** @ -40 to 85°C

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April 20, 2016

ZSSC3027

Low-Power, High-Resolution

Datasheet

16-Bit Sensor Signal Conditioner

ZSSC3027

VDDB

Vreg int

Block Diagram

VDD

V_TP

Temperature

Reference

Sensor

Voltage

Regulator

AGND / CM

Generator

Bias Current

Generator

VSS

V_TN

Power Ctr.

ZSSC3027

18-bit DSP Core

(Calculations,

Communication)

A

EOC

INP

INN

D

Sensor

Bridge

Pre-

Amplifier

16 Bit

VSSB

SCLK/SCL

SS

MOSI/SDA

MISO

SPI

MTP

System

Control

Unit

Clock

Generator

I²C^TM

ROM

Power-ON

Reset

Ring

Oscillator

Applications

SEL

 Barometric altitude measurement for

portable navigation or emergency call

systems

 Altitude measurement for car navigation

 Inside hard disk pressure measurement

 Weather forecast

 Fan control

 Industrial, pneumatic, and liquid pressure

 High-resolution temperature measurements

Ordering Information (See section 6 in the data sheet for additional options for delivery)

Sales Code Description Delivery Package

ZSSC3027AC1B Die—temperature range: –40°C to +85 °C

ZSSC3027AC6B Die—temperature range: –40°C to +85 °C

ZSSC3027AC7B Die—temperature range: –40°C to +85°C

Wafer (304µm) unsawn, tested

Wafer (725µm) unsawn, tested

Wafer (200µm) unsawn, tested

ZSSC3026-KIT

Evaluation Kit for ZSSC3026, including boards, cable, software, and 1 ZSSC3026 PQFN24 sample

(equivalent to ZSSC3027—kit is recommended for evaluation of the capabilities of the ZSSC3027)

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ZSSC3027 Datasheet

Table of Contents

Table of Figures....................................................................................................................................................4

List of Tables ........................................................................................................................................................5

1

IC Characteristics ..........................................................................................................................................6

1.1. Absolute Maximum Ratings....................................................................................................................6

1.2. Operating Conditions..............................................................................................................................6

1.3. Electrical Parameters .............................................................................................................................7

1.4. Power Supply Rejection Ratio (RSRR) vs. Frequency...........................................................................9

Circuit Description .......................................................................................................................................10

2.1. Brief Description ...................................................................................................................................10

2.2. Signal Flow and Block Diagram............................................................................................................10

2.3. Analog Front End..................................................................................................................................12

2.3.1. Amplifier .........................................................................................................................................12

2.3.2. Analog-to-Digital Converter............................................................................................................13

2.3.3. Temperature Measurement ...........................................................................................................17

2.3.4. Bridge Supply.................................................................................................................................17

2.4. Digital Section.......................................................................................................................................17

2.4.1. Digital Signal Processor (DSP) Core .............................................................................................17

2.4.2. MTP Memory..................................................................................................................................17

2.4.3. Clock Generator.............................................................................................................................18

2.4.4. Power Supervision .........................................................................................................................18

2.4.5. Interface .........................................................................................................................................18

Functional Description.................................................................................................................................19

3.1. Power Up..............................................................................................................................................19

3.2. Measurements......................................................................................................................................19

3.3. Operational Modes ...............................................................................................................................19

3.4. Command Interpretation.......................................................................................................................21

3.4.1. SPI/I²C™ Commands ....................................................................................................................21

3.5. Communication Interface......................................................................................................................24

3.5.1. Common Functionality ...................................................................................................................24

3.5.2. SPI .................................................................................................................................................25

3.5.3. I²C™...............................................................................................................................................28

3.6. Memory.................................................................................................................................................29

3.6.1. Programming Memory ...................................................................................................................30

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ZSSC3027 Datasheet

3.6.2. Memory Status Commands ...........................................................................................................30

3.6.3. Memory Contents...........................................................................................................................31

3.7. Calibration Sequence ...........................................................................................................................37

3.7.1. Calibration Step 1 – Assigning Unique Identification.....................................................................37

3.7.2. Calibration Step 2 – Data Collection..............................................................................................37

3.7.3. Calibration Step 3 – Coefficient Calculations.................................................................................38

3.8. The Calibration Math ............................................................................................................................39

3.8.1. Bridge Signal Compensation .........................................................................................................39

3.8.2. Temperature Signal Compensation ...............................................................................................42

Die Pad Assignments..................................................................................................................................43

Quality and Reliability..................................................................................................................................44

Ordering Sales Codes.................................................................................................................................44

Related Documents.....................................................................................................................................45

Glossary ......................................................................................................................................................45

Document Revision History.........................................................................................................................46

4

5

6

7

8

9

Table of Figures

Figure 2.1 ZSSC3027 Functional Block Diagram...........................................................................................11

Figure 2.2 ADC Offset.....................................................................................................................................16

Figure 3.1 Operational Flow Chart: Power Up................................................................................................20

Figure 3.2 Operational Flow Chart: Command Mode and Normal Mode .......................................................21

Figure 3.3 SPI Configuration CPHA=0 ...........................................................................................................25

Figure 3.4 SPI Configuration CPHA=1 ...........................................................................................................26

Figure 3.5 SPI Command Request.................................................................................................................26

Figure 3.6 SPI Read Status ............................................................................................................................27

Figure 3.7 SPI Read Data...............................................................................................................................27

Figure 3.8 I²C™ Command Request ..............................................................................................................28

Figure 3.9 I²C™ Read Status..........................................................................................................................28

Figure 3.10 I²C™ Read Data ............................................................................................................................29

Figure 3.11 Memory Program Operation ..........................................................................................................30

Figure 4.1 ZSSC3027 Pad Assignments ........................................................................................................43

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ZSSC3027 Datasheet

List of Tables

Table 1.1

Table 1.2

Table 1.3

Table 1.4

Table 2.1

Table 2.2

Table 2.3

Table 2.4

Table 2.5

Table 2.6

Table 2.7

Maximum Ratings ............................................................................................................................6

Operating Conditions .......................................................................................................................6

Requirements for VDD Power-on Reset..........................................................................................7

Electrical Parameters.......................................................................................................................7

Amplifier Gain: Stage 1..................................................................................................................12

Amplifier Gain: Stage 2..................................................................................................................12

Gain Polarity ..................................................................................................................................13

MSB/LSB Segmentation Settings for Bridge Measurement..........................................................14

MSB/LSB Segmentation Settings for Temperature Measurement................................................14

ADC Conversion Times for a Single A2D Conversion...................................................................14

Typical Conversion Times vs. Noise Performance for 16-Bit Results with Full Sensor Signal

Conditioning for AZBM, BM, AZTM, and TM.................................................................................15

Table 2.8

Table 3.1

Table 3.2

Table 3.3

Table 3.4

Table 3.5

Table 3.6

Table 3.7

Table 3.8

Table 4.1

ADC Offset Settings for the Measurement Configuration Register BM_config.............................16

SPI/I²C™ Commands ....................................................................................................................22

Get_Raw Commands ....................................................................................................................23

General Status Byte.......................................................................................................................24

Status Byte for Read Operations...................................................................................................24

Status Byte for Write Operations ...................................................................................................24

Mode Status...................................................................................................................................25

Memory Status Word.....................................................................................................................30

MTP Memory Content Assignments..............................................................................................31

Pad Assignments...........................................................................................................................43

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ZSSC3027 Datasheet

1

IC Characteristics

1.1. Absolute Maximum Ratings

Note: The absolute maximum ratings are stress ratings only. The ZSSC3027 might not function or be operable

above the recommended operating conditions. Stresses exceeding the absolute maximum ratings might also

damage the device. In addition, extended exposure to stresses above the recommended operating conditions

might affect device reliability. IDT does not recommend designing to the “Absolute Maximum Ratings.”

Table 1.1 Maximum Ratings

PARAMETER

SYMBOL

Vss

Min

0

TYP

MAX

0

UNITS

Voltage Reference

V

Analog Supply Voltage

V_DD

-0.4

3.63

Voltage at all Analog and Digital IO Pins

V_{A_IO}, V_{D_IO}

I_IN

V_HBM1

T_STOR

-0.5

-100

4000

-50

V_DD+0.5

100

-

V

mA

V

Input Current into any Pin Except SDA, CLK ¹⁾and Supply Pins ²⁾

Electrostatic Discharge Tolerance – Human Body Model (HBM1) ³⁾

Storage Temperature

125

°C

1)

2)

3)

Latch-up current limit for SCLK/SCL and MOSI/SDA: ±70mA.

Latch-up resistance; reference for pin is 0V.

HBM1: C = 100pF charged to V_HBM1with resistor R = 1.5kΩ in series based on MIL 883, Method 3015.7. ESD protection

referring to the Human Body Model is tested with devices in ceramic dual in-line packages (CDIP) during product qualification.

1.2. Operating Conditions

The reference for all voltages is Vss.

Table 1.2 Operating Conditions

PARAMETER

Supply Voltage

SYMBOL

V_DD

MIN

TYP

MAX

3.6

UNIT

V

1.7

-

VDD Rise Time

t_VDD

200

1.8

μs

Bridge Current

I_VDDB

mA

16.5

85

Operation Temperature Range—Standard

T_AMB

CL

-40

-

°C

nF

External capacitance between VDDB and VSS

0.01

50

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ZSSC3027 Datasheet

A dynamic power-on-reset circuit is implemented in order to achieve minimum current consumption in idle mode.

The VDD low level and the subsequent rise time and VDD rising slope must meet the requirements in Table 1.1 to

guarantee an overall IC reset; lower VDD low levels allow slower rising of the subsequent on-ramp of VDD. Other

combinations might also be possible. For example, the reset trigger can be influenced by increasing the power-

down time and lowering the VDD rising slope requirement.

Table 1.3 Requirements for VDD Power-on Reset

PARAMETER

Power Down Time (duration of VDD Low Level)

VDD Low Level

SYMBOL

t_SPIKE

MIN

3

TYP

MAX

UNIT

µs

-

0.2

-

VDD_low

SR_VDD

0

V

VDD Rising Slope

10

V/ms

1.3. Electrical Parameters

All parameter values are valid only under the specified operating conditions. All voltages are referenced to Vss.

Table 1.4 Electrical Parameters

Note: See important table notes at the end of the table.

Parameter

Symbol

Conditions/Comments

Min

Typ

Max

Unit

Supply

Bridge Supply Voltage,

ADC Reference Voltage

V_DDB

Internally generated

1.60

1.67

1.74

V

Active State, average

Sleep State, idle current

V_DD= 1.8V

930

20

1500

250

µA

nA

dB

Current Consumption

I_VDD

Power Supply Rejection

17

32

20·log₁₀(V_DD/V_DDB

)

PSR_VDD

V_DD,prog

I_VDD,prog

V_DD= 2V

dB

V

(see section 1.4)

Memory Program Voltage

Mean Program Current

Required voltage level at VDD pin

2.9

3.6

20

Mean current consumption during

multiple-time memory (MTP)

programming cycle at VDD

6

mA

MTP program at VDD pin,

dynamic switch-on current draw

Peak Program Current

I_prog,max

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ZSSC3027 Datasheet

Parameter

Symbol

Conditions/Comments

Min

Typ

Max

Unit

Analog-to-Digital Converter (ADC, A2D)

Resolution

r_ADC

f_ADC

10

16

Bit

ADC Clock Frequency

Internal ADC clock

0.92

1

1.08

MHz

V_DDB

Reference Voltage n

Reference Voltage p

V_refn

V_refp

See section 2.3.2.

0.03

*

V_DDB

0.97

*

Offset

A2D_Offset

INL_ADC

8-step programmable offset

Tested / verified within design

1/16

-4

8/16

+4

Integral Nonlinearity (INL)

Differential Nonlinearity

-

LSB

DNL_ADC

-1

+1

Conversion Rate, 16-Bit

Single

Conversions per second for single

16-bit A2D conversion

f_S,raw

6

-

355

Hz

Amplifier

Gain

G_amp

G_err

32 steps

13.2

-2.5

72

Gain Error

Referenced to nominal gain

-

2.5

%

Sensor Signal Conditioning Performance

IC Accuracy Error ¹⁾

Err_A,IC

Accuracy error for ideally linear

sensor (temperature and

measurand)

0.01

175

%FSO

Hz

Conversion per second for fully

corrected 16-bit measurement

Conversion Rate, 16-Bit SSC f_{S, SSC}

3

Input

Input Voltage Range

Bridge Resistance

Power-Up

V_INP, V_INN

Input voltage range at INP and INN

0.65

1

1.05

50

V

Full power supply disturbance

rejection (PSRR) capabilities

Reduced PSRR, but full

functionality

10

kΩ

R_BR

100

999

Ω

V

_DDramp up to interface

t_STA1

t_STA2

t_WUP1

t_WUP2

1

ms

communication (see section 3.1)

Start-up Time

Wake-up Time

V_DDramp up to analog operation

2.5

0.5

2

Sleep to Active State interface

communication

Sleep to Active State analog

operation

Oscillator

Internal Oscillator Frequency

f_CLK

3.7

4

4.3

MHz

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ZSSC3027 Datasheet

Parameter

Symbol

Conditions/Comments

Min

Typ

Max

Unit

Internal Temperature Sensor

For both temperature ranges:

-40°C to +85°C

Temperature Resolution

0.003

K/LSB

Interface and Memory

Maximum capacitance at MISO

line: 40pF @ V_DD=1.8V

SPI Clock Frequency

I²C™ Clock Frequency

Program Time

f_C,SPI

20

3.4

600

MHz

µs

f_C,I2C

MTP programming time per 16-bit

register

t_prog

500

10

Data Retention ²⁾

t_{RET_MTP}

1000h @ 125°C

a

1)

2)

Percentage referred to maximum full-scale output (FSO); e.g. for 16-bit measurements: Err_A,IC[%FSO] = 100 · MAX{ | ADC_meas– ADC_ideal| } / 2¹⁶

.

With maximum ambient temperature of 125°C.

1.4. Power Supply Rejection Ratio (RSRR) vs. Frequency

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ZSSC3027 Datasheet

2 Circuit Description

2.1. Brief Description

The ZSSC3027 provides a highly accurate amplification of bridge sensor signals. The compensation of sensor

offset, sensitivity, temperature drift, and non-linearity is accomplished via an 18-bit DSP core running a correction

algorithm with calibration coefficients stored in a multiple-time programmable (MTP) memory (see section 2.4.2

regarding limitations). The ZSSC3027 can be configured for a wide range of resistive bridge sensor types. A

digital interface (SPI or I²C™*) enables communication. The ZSSC3027 supports two operational modes: Normal

Mode and Command Mode. Normal Mode is the standard operating mode. Typically in Normal Mode, the

ZSSC3027 wakes up from a Sleep State (low power), runs a measurement in Active State, and automatically

returns to the Sleep State. (See section 3.3 for details on operational modes.)

2.2. Signal Flow and Block Diagram

See Figure 2.1 for the ZSSC3027 block diagram. The sensor bridge supply V_DDBand the power supply for analog

circuitry are provided by a voltage regulator, which is optimized for power supply disturbance rejection (PSRR).

See section 1.4 for a graph of PSRR versus frequency. To improve noise suppression, the digital blocks are

powered by a separate voltage regulator. A power supervision circuit monitors all supply voltages and generates

appropriate reset signals for initializing the digital blocks.

The state machine controls the analog circuitry to perform the three measurement types: bridge, temperature, and

offset measurement. The multiplexer selects the signal input to the amplifier, which can be the external signals

from the input pins INP and INN, the internal temperature reference sensor signals, or an input short for

measuring offset. A full measurement request will trigger an automatic sequence of all measurement types and all

input signals. The Temperature Reference Sensor block is based on a resistive sensing element.

* I²C™ is a trademark of NXP.

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April 20, 2016

ZSSC3027 Datasheet

Figure 2.1 ZSSC3027 Functional Block Diagram

VDDB

Vreg int

VDD

VSS

V_TP

Temperature

Reference

Sensor

Voltage

Regulator

AGND / CM

Generator

Bias Current

Generator

V_TN

Power Ctr.

ZSSC3027

18-bit DSP Core

(Calculations,

Communication)

A

EOC

INP

INN

D

16 Bit

Sensor

Bridge

Pre-

Amplifier

VSSB

SCLK/SCL

SS

MOSI/SDA

MISO

SPI

MTP

System

Control

Unit

Clock

Generator

I²C^TM

ROM

Power-ON

Reset

Ring

Oscillator

SEL

The amplifier consists of two stages with programmable gain values. The 1/f noise and inherent offset are

suppressed by auto-zero and chopper stabilizer techniques. This auto-zero sequence is performed before each

bridge sensor and temperature measurement to compensate for the inherent offset of the amplifier.

The ZSSC3027 employs a 2-stage analog-to-digital converter (ADC) based on switched-capacitor technique with

inherit low-pass behavior and noise suppression. The programmable resolution from 10 to 16 bits provides

flexibility for adapting the conversion characteristics. To improve power supply noise suppression, the ADC uses

the bridge supply V_DDBas its reference voltage.

The remaining IC-internal offset and the sensor element offset, i.e., the overall system offset for the amplifier and

ADC, can be canceled by an offset and auto-zero measurement, respectively.

The DSP accomplishes the auto-zero, span, and 1^stand 2^ndorder temperature compensation of the measured

bridge signal. The correction coefficients are stored in the MTP memory.

The ZSSC3027 supports SPI and I²C™ interface communication for controlling the ZSSC3027, configuration, and

measurement result output.

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ZSSC3027 Datasheet

2.3. Analog Front End

2.3.1. Amplifier

The amplifier has a differential architecture and consists of two stages. The amplification of each stage and the

sensor bridge gain polarity are programmable via settings in the Measurement Configuration Register BM_config

(address 10_HEX; see section 3.6.3) in the MTP memory (see section 2.4.2). The first five bits of BM_config are the

programmable gain settings Gain_stage1 and Gain_stage2. The options for the programmable gain settings are

listed in Table 2.1 and Table 2.2.

Table 2.1 Amplifier Gain: Stage 1

Gain_stage1

BM_config Bit G1

BM_config Bit G0

Stage 1 Gain Setting

0

1

12

20

1

0

1

30

40

Table 2.2 Amplifier Gain: Stage 2

Gain_stage2

BM_config Bit G4

BM_config Bit G3

BM_config Bit G2

Stage 2 Gain Setting

0

1

0

1

0

1

0

1

0

1

0

1

0

1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

If needed, the polarity of the sensor bridge gain can be reversed by setting the Gain_polarity bit, which is bit 5 in

the BM_config register (see section 3.6.3). Changing the gain polarity is achieved by inverting the chopper clock.

Table 2.3 gives the settings for the Gain_polarity bit. This feature enables applying a sensor to the ZSSC3027

with swapped input signals at INN and INP; e.g., to avoid crossing wires for the final sensor module’s assembly.

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ZSSC3027 Datasheet

Table 2.3 Gain Polarity

Gain_polarity (BM_config Bit 5)

Gain

Setting Description

0

1

+1

-1

No polarity change.

Gain polarity is inverted.

The inherent amplifier offset is suppressed by means of auto-zero and chopper techniques. The optimal gain (and

offset) setup for a specific sensor element can be determined by these steps:

1) Collect sensor elements’ characteristic, statistical data (over temperature, ambient sensor parameter, and

over production tolerances):

a. Minimum differential output voltage:

b. Maximum differential output voltage:

V_min

V_max

Note: The best possible setup can only be determined if the absolute value of V_maxis bigger than the

absolute value of V_min. If this is not the case, the gain polarity should be reversed.

2) If V_minand V_maxhave different signs (normally: V_maxis positive and V_minis negative), then the required

ADC offset shift can be selected using this ratio: Ratio_Offset= |V_min| / (V_max– V_min).

In this case, the respective offset setup (A2D_offset) is the nearest integer of multiples of 1/16 in the

range of 1/16 to 8/16 (see Table 2.8): A2D_offset = Round_to_x16^th{Ratio_Offset}.

3) Determine which of the two following cases is valid.

a. If Ratio_Offset– A2D_offset ≤ 0 then calculate

Theoretical optimum gain: Gain_opt=(1 – A2D_offset) V_ref/ V_max

*

b. If Ratio_Offset– A2D_offset > 0 then calculate

Theoretical optimum gain: Gain_opt= A2D_offset V_ref/ |V_min

|

*

with:

V_ref= V_refp– V_refn= 0.94·V_DDB,min≈ 1.5V

Finally, select the setup gain (Gain_setup) as the nearest gain to Gain_opt, where Gain_setup≤ Gain_opt.

2.3.2. Analog-to-Digital Converter

A second-order charge-balancing analog-to-digital converter (ADC) is used to convert the amplifier signal. To

allow optimizing the trade-off between conversion time and resolution, the conversion is split into a MSB coarse

conversion and an LSB fine conversion. The final ADC resolution is determined by MSB + LSB. For the bridge

measurement, the MSB-LSB segmentation is programmable via the Msb and Lsb settings in the BM_config

register (10_HEX; see section 3.6.3) stored in the MTP memory (see section 2.4.2). For the temperature

measurement, the MSB-LSB segmentation is programmable via the Temp_ADC settings in the BM_config

register.

The conversion time is proportional to 2^MSB+2^LSB. During the MSB coarse conversion, the ADC input signal is

sampled and integrated 2^MSBtimes, resulting in inherit low-pass behavior and noise suppression. The longer the

MSB coarse conversion is, the better the noise suppression is. Possible settings are listed below in Table 2.4 and

Table 2.5.

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ZSSC3027 Datasheet

Table 2.4 MSB/LSB Segmentation Settings for Bridge Measurement

Msb Setup Bits [7:6]

in BM_config

Number of MSB Coarse

Conversion Bits

Lsb Setup Bits [9:8]

Number of LSB Fine

Conversion Bits

in BM_config

00_BIN

01_BIN

10_BIN

11_BIN

10

12

14

16

00_BIN

01_BIN

10_BIN

11_BIN

0

2

4

6

Table 2.5 MSB/LSB Segmentation Settings for Temperature Measurement

Temp_ADC Setup Bits

[14:13] in BM_config

Number of MSB Coarse

Conversion Bits

Number of LSB Fine

Conversion Bits

01_BIN

10_BIN

11_BIN

16

10

12

0

6

4

Setup according to IDT configuration in reserved memory

(recommended setup for best performance and speed trade-off)

00_BIN

Table 2.6 gives the ADC conversion times for the MSB/LSB settings (yellow indicates 16-bit setups). Useful MSB/

LSB setups are with LSB = 0 (MSB-only conversions) or combinations that result in MSB + LSB ≤ 16. Resolutions

beyond 16-bit mainly digitize the collected front-end noise and typically do not improve the system performance.

Table 2.6 ADC Conversion Times for a Single A2D Conversion

MSB

LSB

Bridge or Temperature Measurement

Conversion Time in µs (typical)

[Bits]

10

12

14

16

10

12

14

10

12

10

0

2

4

6

1170

4625

18450

73745

1180

4635

18460

1200

4660

1300

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April 20, 2016

ZSSC3027 Datasheet

Table 2.7 shows the trade-off between noise performance and typical conversion time for 16-bit results for a sig-

nal that has been fully conditioned using 4 single measurements: the auto-zero bridge measurement (AZBM), the

bridge measurement (BM), auto-zero temperature measurement (AZTM), and temperature measurement (TM).

Table 2.7 Typical Conversion Times vs. Noise Performance for 16-Bit Results with Full Sensor Signal

Conditioning for AZBM, BM, AZTM, and TM

Note: The pink shading indicates IDT’s recommended ADC segmentation for temperature sensor measurement.

ADC Segmentation:

Temperature Sensor

[MSB/LSB]

Typical Measurement

Duration, MEASURE, (AC_HEX

[ms]

Typical 3-Sigma Noise for

SSC-Corrected Output ¹⁾

[counts]

ADC Segmentation: Bridge

)

Sensor [MSB/LSB]

10 / 6

12 / 4

16 / 0

10 / 6

12 / 4

14 / 2

16 / 0

10 / 6

12 / 4

14 / 2

16 / 0

10 / 6

12 / 4

14 / 2

16 / 0

5.8

9.6

7.4

6.8

6.6

9.5

7.3

6.7

6.3

8.1

6.6

5.3

5.2

13.2

43.0

165

13.2

20.5

50.5

170.3

162.6

170.3

200.3

319.5

1)

Reference noise values were obtained with this setup: 17kΩ sensor bridge, 25°C, Gain=54, ADC shift=-1/16 through 15/16 (see below), VDD=1.8V.

The ADC offset is programmable in 8 steps so that the ADC input voltage range can be adapted to the voltage

range at the input pins INP and INN. Possible ADC input voltages and references voltages V_refnand V_refpare

shown in Figure 2.2, where V_AGND≈ V_DDB/2. The ADC offset is controlled by the A2D_Offset setting bits [12:10] in

the Measurement Configuration Register BM_config (10_HEX; see section 3.6.3) in the MTP memory (see section

2.4.2). The ADC offset settings are listed in Table 2.8. See section 1.4 for typical values for V_refnand V_refp

.

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ZSSC3027 Datasheet

Figure 2.2 ADC Offset

ADC_out

1

V_INP, A2D_Offset = 1/16

V_INN, A2D_Offset = 1/16

8/16

V_INP, A2D_Offset = 8/16

V_INN, A2D_Offset = 8/16

1/16

V_IN, V_IP

0

V_refn

V_AGND

V_refp

Table 2.8 ADC Offset Settings for the Measurement Configuration Register BM_config

Z2

Z1

Z0

ADC Differential Input Range/V_ref

Where V_ref= V_refp- V_refn

A2D_Offset

(BM_config bit 12)

(BM_config bit 11)

(BM_config bit 10)

0

1

0

1

0

1

0

1

0

1

0

1

0

1

-1/16 to 15/16

-2/16 to 14/16

-3/16 to 13/16

-4/16 to 12/16

-5/16 to 11/16

-6/16 to 10/16

-7/16 to 9/16

-8/16 to 8/16

1/16

2/16

3/16

4/16

5/16

6/16

7/16

8/16

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ZSSC3027 Datasheet

2.3.3. Temperature Measurement

The ZSSC3027 provides an internal temperature sensor measurement to allow compensation for temperature

effects. See section 1.3 for the temperature sensor resolution. The temperature sensor uses bipolar transistors.

Any transistor circuitry mismatch is suppressed by the dynamic element matching technique. The temperature

output signal is a differential voltage that is adapted by the amplifier for the ADC input.

For temperature measurements, the ADC offset and amplifier gain setting are defined by IDT. The ADC MSB/LSB

segmentation is programmable by the user for optimizing noise immunity or conversion time (see section 2.3.2).

2.3.4. Bridge Supply

The ZSSC3027 provides dedicated bridge supply pins VDDB and VSSB. The ADC reference voltages for the

sensor bridge measurement are derived from these internal voltages so that bridge supply disturbances are

suppressed. The current drive ability of V_DDBis limited (see I_VDDBin section 1.2).

2.4. Digital Section

2.4.1.

Digital Signal Processor (DSP) Core

The DSP Core block performs the algorithm for correcting the sensor signal. The resulting coefficients are stored

in the MTP memory. When the measurement results are available, the "end of conversion" signal is set at the

EOC pin. The internal EOC information is valid only if both the measurement and calculation have been

completed.

2.4.2.

MTP Memory

The ZSSC3027’s memory is designed with an OTP (one-time programmable) structure. The memory is organized

in 4 one-time programmable pages. When data in the currently valid memory page needs to be updated, normally

a new page must be selected by increasing the page counter and the whole memory content must be written in its

updated version. The user has access to a 24 x 16 bit storage area for values such as calibration coefficients.

Dedicated calibration values are stored in an area not accessible to the user. The required programming voltage

is generated internally in the ZSSC3027 whereas increased ZSSC3027 power supply requirements must be

fulfilled during programming (see Memory Programming Voltage in section 1.3). There is no over-write or erase

function for the MTP memory. See section 3.4.1 for further details.

The physical memory function is such that each single bit that has not yet been set to 1 (i.e., remains 0) can still

be changed to 1, so it is possible to (partially) re-program an MTP register as shown in the following example:

•

Assume MTP address 11_HEXwas written with 8421_HEXwhich is 1000 0100 0010 0001_BIN.

Changing the register contents to A6A7_HEX(i.e., 1010 0110 1010 0111_binary) can be achieved by either

writing A6A7_HEX(any already written bit will be ignored automatically) or just writing the difference

compared to 8421_HEX, which is 2286_HEX

The content of a re-written register can generally be determined by

content_Register= content_old(BITWISE_OR) content_new

.

If content_Registerequals content_new, a re-write is possible; e.g., this is not the case for content_old= FFFF_HEXand

content_new≠ FFFF_HEX. Depending on the former and the newly intended MTP addresses and register contents, a

re-programming could be possible.

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ZSSC3027 Datasheet

2.4.3.

Clock Generator

The clock generator, implemented as a ring oscillator, provides a 4MHz clock signal. The frequency is trimmed

during production test.

2.4.4.

Power Supervision

The power supervision block as a part of the voltage regulator combined with the digital section monitors all

power supplies to ensure a defined reset of all digital blocks during power-up or power supply interruptions.

2.4.5.

Interface

The ZSSC3027 can communicate with the user’s PC via an SPI or I²C™ interface ^†. The interface type is select-

able via the voltage level on the SEL pin:

• SEL = 0 -> SPI Mode

• SEL = 1 -> I²C™ Mode

If the SEL pin is not connected, I²C™ communication will be selected (IC-internal pull-up at SEL pin). The SPI-

specific pins (SS, MISO) do not need to be connected for I²C™ operation.

To also provide interface accessibility in Sleep State (all features inactive except for the digital interface logic), the

interface circuitry is directly supplied by VDD.

† Functional I²C™ interface properties correspond to the NXP I²C™ bus specification Rev. 0.3 (June 2009).

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ZSSC3027 Datasheet

3

Functional Description

3.1.

Power Up

Specifications for this section are given in sections 1.2 and 1.3. On power-up, the ZSSC3027 communication

interface is able to receive the first command after a time t_STA1from when the VDD supply is within operating

specifications. The ZSSC3027 can begin the first measurement after a time of t_STA2from when the VDD supply is

operational. The wake up time from Sleep State to Active State (see section 3.3) after receiving the activating

command is defined as t_WUP1and t_WUP2(see section 1.3). In Command Mode, subsequent commands can be sent

after t_WUP1. The first measurement starts after t_WUP2if a measurement request was sent.

3.2.

Measurements

Available measurement procedures are

• AZBM: auto-zero bridge measurement

• BM: bridge measurement

• AZTM: auto-zero temperature measurement

• TM: temperature measurement

AZBM: The configuration for bridge measurements is loaded. The Multiplexer block connects the amplifier input

to the AGND analog ground reference. An analog-to-digital conversion is performed so that the inherent system

offset for the bridge configuration is converted by the ADC to a 16-bit digital word.

BM: The configuration for bridge measurements is loaded. The Multiplexer connects the amplifier input to the

bridge pins INP and INN. An analog-to-digital conversion is performed. The result is a 16-bit digital word.

AZTM: The configuration for temperature measurements is loaded. The Multiplexer connects the amplifier input to

AGND. An analog-to-digital conversion is performed so that the inherent system offset for the temperature

configuration is converted by the ADC to a 16-bit digital word.

TM: The configuration for temperature measurements is loaded. The Multiplexer connects the Amplifier input to

the internal temperature sensor. An analog-to-digital conversion is performed. The result is a 16-bit digital word.

The typical application’s measurement cycle is a complete SSC measurement (using the command AC_HEX) with

AZBM, BM, AZTM, and TM followed by a signal correction calculation.

3.3.

Operational Modes

Figure 3.1 illustrates the ZSSC3027 power-up sequence and subsequent operation depending on the selected

interface communication mode (I²C™ or SPI) as determined by the SEL pin voltage level (see section 2.4.5). With

either interface, after the voltage regulators are switched on, the ZSSC3027’s low voltage section (LV) is active

while the related interface configuration information is read from memory. Then the LV section is switched off, the

ZSSC3027 goes into Sleep State, and the interface is ready to receive commands. Since the interface is always

powered by V_DD, it is referred to as the high voltage section (HV).

See Table 3.1 for definitions of the commands. Figure 3.2 shows the ZSSC3027 operation in Normal Mode and

Command Mode including when the LV and HV sections are active as indicated by the color legend.

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ZSSC3027 Datasheet

The Normal Mode automatically returns to Sleep State after executing the requested measurements. In

Command Mode, the ZSSC3027 remains active if a dedicated command (Start_NOM) was sent, which is helpful

during calibration. Command Mode can only be entered if Start_CM is the first command received after POR.

Figure 3.1 Operational Flow Chart: Power Up

IC Power On

I²C™ Interface

SPI Interface

IO_mode = I²C^TM

yes (I²C^TM

)

SEL==1

no (SPI)

IO_mode = SPI

Command: load IC-I²C Addr.

Power up LV

Switch off pull-up at SEL

Command: load I/O setup

Power up LV

LV Operation

Save: IC I²C Address /

Data / Status

LV Operation

CommandMode

==active

Save: Setup / Data /

Status

yes

no

Power down (switch

off LV and wait for

command)

CommandMode

==active

yes

no

Power down (switch

off LV and wait for

command)

Receive: Command

Received I²C

Slave_Addr == IC I²C

Slave_Addr

no

yes

SS == 1

Read_bit == 1

(Data fetch)

yes

Receive: Command

yes

Execute: Data Fetch

Received CMD ==

Read_DF

yes

Color Legend:

Execute: Data Fetch

LV-Operation

HV-Operation

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ZSSC3027 Datasheet

Figure 3.2 Operational Flow Chart: Command Mode and Normal Mode

Start LV

Get command from HV

CM active

CMD==Start_CM

yes

Receive: Command

INVALID_CMD

Case (Command)

no

Start_NOM

Case (Command)

REGULAR_CMD

CM inactive

INVALID_CMD

REGULAR_CMD

Execute: Command

Color Legend:

LV Operation

HV Operation

End LV

Command Mode

Sleep Mode

3.4. Command Interpretation

3.4.1.

SPI/I²C™ Commands

The user-accessible section of memory includes addresses 00_HEXthrough 17_HEXin the OTP memory that is

designated by the user memory page pointer. Because each of the four OTP memory pages cannot be rewritten

or erased, the memory page pointer must be incremented to the next OTP memory page in order to write to

memory again (see Table 3.1 for the command). After all four user-accessible OTP memory pages have been

used, further write operations are not possible and the “Memory Full” bit is returned as set in the status byte after

write operations (see section 3.5.1).

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ZSSC3027 Datasheet

The SPI/I²C™ commands supported by the ZSSC3027 are listed in Table 3.1. The command to read an address

in the user memory is the same as its address. The command to read the 16-bit memory status of the data at an

address in user memory is the address plus 20_HEX. The command to write to an address in user memory is the

address plus 40_HEX

.

There is a IDT-reserved section of memory that can be read but not over-written by the user.

Table 3.1 SPI/I²C™ Commands

Note: Every return starts with a status byte followed by the data word as described in section 3.5.1.

Command

(Byte)

Normal

Mode

Command

Mode

Return

16-bit user data

Description

00_HEXto 17_HEX

Read data in the user memory address

(00_HEXto 17_HEX) matching the command

(might not be using all addresses).

yes

20_HEXto 37_HEX

16-bit user memory status

Read memory status for address specified by

command minus 20_HEX(addresses 00_HEXto

17_HEXrespectively; see section 3.6.2 for a

description of the memory status).

yes

no

yes

40_HEXto 57_HEX

followed by data

(0000_HEXto

—

Write data to user memory at address

specified by command minus 40_HEX

(addresses 00_HEXto 17_HEXrespectively; might

not be using all addresses).

yes

FFFF_HEX

)

70_HEXto 7E_HEX

16-bit IDT-reserved memory Read data in IDT-reserved memory at

data

address specified by command minus 70_HEX

(second set of addresses 00_HEXto 0E_HEX

respectively).

80_HEXto 8E_HEX

16-bit IDT-reserved memory Read memory status bytes for IDT-reserved

status

memory data at address specified by

command minus 80_HEX(second set of

addresses 00_HEXto 0E_HEXrespectively; see

section 3.6.2 for a description of the memory

status bytes).

5E_HEX

—

Increment user memory page pointer.

no

yes

Get_Raw This command can be used to

perform a measurement and write the raw

ADC data into the output register. The LSB of

the command determines how the AFE

configuration register is loaded for the

Get_Raw measurement (see Table 3.2).

A0_HEXto A7_HEX

followed by

XXXX_HEX

16-bit wide raw data

yes

(see Table 3.2)

Start_NOM Exit Command Mode and

transition to Normal Mode.

A8_HEX

A9_HEX

—

no

yes

no

Start_CM Exit Normal Mode and transition

yes

to Command Mode.

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ZSSC3027 Datasheet

Command

(Byte)

Normal

Mode

Command

Mode

Return

Description

Write_ChecksumC If not yet written, the

checksum for the valid user MTP page is cal-

culated and written to MTP.

AA_HEX

—

no

yes

Measure Triggers full measurement cycle

(AZBM, BM, AZTM, and TM, as described in

section 3.2) and calculation and storage of

data in interface (configurations from MTP).

AC_HEX

16-bit fully corrected bridge

measurement data + 16-bit

corrected internal

yes

temperature

NOP Only valid for SPI (see 3.5.1 and 3.5.2).

FX_HEX

Status followed by last data

yes

Table 3.2 Get_Raw Commands

Command

Measurement

AFE Configuration Register

A0_HEXfollowed by 0000_HEX

A1_HEXfollowed by ssss_HEX

BM – Bridge Measurement

BM_Config

ssss is the user’s configuration setting for the measure-

ment provided via the interface. The format and pur-

pose of configuration bits must be according to the

definitions for BM_Config.

A2_HEXfollowed by 0000_HEX

A3_HEXfollowed by ssss_HEX

BM-AZBM – Auto-Zero Corrected

Bridge Measurement ¹⁾

BM_Config

BM-AZBM – Auto-Zero Corrected

Bridge Measurement ²⁾

ssss is the user’s configuration setting for the measure-

ment provided via the interface. The format and pur-

pose of configuration bits must be according to the

definitions for BM_Config.

A4_HEXfollowed by 0000_HEX

A5_HEXfollowed by ssss_HEX

TM – Temperature Measurement

IDT-defined register

ssss is the user’s configuration setting for the measure-

ment provided via the interface. The format and pur-

pose of configuration bits must be according to the

definitions for BM_Config being valid for temperature

measurement in this case (bits [15:13] will be ignored).

A6_HEXfollowed by 0000_HEX

A7_HEXfollowed by ssss_HEX

TM-AZTM – Auto-Zero Corrected

Temperature Measurement ¹⁾

IDT-defined register

TM-AZTM – Auto-Zero Corrected

Temperature Measurement ²⁾

ssss is the user’s configuration setting for the measure-

ment provided via the interface. The format and pur-

pose of configuration bits must be according to the

definitions for BM_Config being valid for temperature

measurement in this case (bits [15:13] will be ignored).

1)

2)

Recommended for raw data collection during calibration coefficient determination using measurement setups pre-programmed in MTP.

Recommended for raw data collection during calibration coefficient determination using un-programmed (i.e., not in MTP), external measurement

setups; e.g., for evaluation purposes.

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ZSSC3027 Datasheet

3.5.

Communication Interface

Common Functionality

3.5.1.

Commands are handled by the command interpreter in the low-voltage (LV) section. Commands that need

additional data are not treated differently than other commands because the high-voltage (HV) interface is able to

buffer the command and all the data that belongs to the command and the command interpreter is activated as

soon as a command byte is received.

Every response starts with a status byte followed by the data word. The data word depends on the previous

command. It is possible to read the same data more than once if the read request is repeated (I²C™) or a NOP

command is sent (SPI). If the next command is not a read request (I²C™) or a NOP (SPI), it invalidates any

previous data.

The status byte contains the following bits (see Table 3.3, Table 3.4, and Table 3.5 for sequence):

• Power indication (bit 6): 1 if the device is powered (V_DDBon); 0 if not powered. This is needed for SPI Mode

where the master reads all zeros if the device is not powered or in power-on reset (POR).

• Busy indication (bit 5): 1 if the device is busy, which indicates that the data for the last command is not

available yet. No new commands are processed if the device is busy.

• Actual ZSSC3027 mode (bits 4:3): 00 = Normal Mode; 01 = Command Mode; 1X = IDT-reserved.

• Memory integrity/error flag (bit 2): 0 if integrity test passed, 1 if test failed. This bit indicates whether the

checksum-based integrity check passed or failed. Correctable errors are not reported but can be queried

with the memory status commands (see section 3.6.2). The memory error status bit is calculated only

during the power-up sequence, so a newly written CRC will only be used for memory verification and status

update after a subsequent ZSSC3027 power-on reset (POR).

• Data transfer/correction (bit 1): If the last command was a memory write, this bit is 0 if the last memory

write was successful (memory not full yet); otherwise it is 1 (e.g., page increase but already on last MTP

page). If the last command was a memory read, this bit is 1 if the data was corrected.

Table 3.3 General Status Byte

Bit

7

6

5

4

3

2

1

0

Meaning

0

Powered?

Busy?

Mode

Memory error?

Internal data

transfer

Special

Table 3.4 Status Byte for Read Operations

Bit

7

6

5

4

3

2

1

0

Meaning

0

Powered?

Busy?

Mode

Memory error?

Data corrected?

ALU saturation?

Table 3.5 Status Byte for Write Operations

Bit

7

6

5

4

3

2

1

0

Meaning

0

Powered?

Busy?

Mode

Memory error?

Memory full? 

Don’t care

MTP write reject?

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ZSSC3027 Datasheet

Table 3.6 Mode Status

Status[4:3]

Mode

00

01

10

Normal Mode

Command Mode

IDT-Reserved

11

Command Mode and Reserved

Further status information is provided by the EOC pin. The EOC pin is set when a measurement and calculation

have been completed.

3.5.2.

SPI

The SPI Mode is available when the SEL pin = 0. The polarity and phase of the SPI clock are programmable via

the CKP_CKE setting in address 02_HEXas described in Table 3.8. CKP_CKE is two bits: CPHA (bit 10), which

selects which edge of SCLK latches data, and CPOL (bit 11), which indicates whether SCLK is high or low when it

is idle. The polarity of the SS signal and pin are programmable via the SS_polarity setting (bit 9). The different

combinations of polarity and phase are illustrated in the figures below.

Figure 3.3 SPI Configuration CPHA=0

CPHA=0

SCLK (CPOL=0)

SCLK (CPOL=1)

MOSI

MISO

MSB

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

LSB

/SS

SAMPLE

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ZSSC3027 Datasheet

Figure 3.4 SPI Configuration CPHA=1

CPHA=1

SCLK (CPOL=0)

SCLK (CPOL=1)

MOSI

MISO

MSB

Bit6

Bit5

Bit4

Bit3

Bit2

Bit1

LSB

/SS

SAMPLE

In SPI mode, each command except NOP is started as shown in Figure 3.5. After the execution of a command

(busy = 0), the expected data can be read as illustrated in Figure 3.6 or if no data are returned by the command,

the next command can be sent. The status can be read at any time with the NOP command (see Figure 3.7).

Figure 3.5 SPI Command Request

Command Request

Command

other than

NOP

CmdDat

<15:8>

CmdDat

<7:0>

MOSI

MISO

Status

Data

Note: A command request always consists of 3 bytes. If the command is shorter, then it must be completed with 0s.

The data on MISO depend on the preceding command.

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ZSSC3027 Datasheet

Figure 3.6 SPI Read Status

Read Status

Command

MOSI

= NOP

MISO

Status

Figure 3.7 SPI Read Data

Read Data

(a) Example: after the completion of a Memory Read command

Command

= NOP

MOSI

MISO

00_HEX

MemDat

<15:8>

MemDat

<7:0>

Status

(b) Example: after the completion of a Full Measurement command (AC_HEX

)

Command

= NOP

MOSI

MISO

00_HEX

BridgeDat BridgeDat TempDat

<15:8> <7:0> <15:8>

TempDat

<7:0>

Status

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ZSSC3027 Datasheet

3.5.3.

I²C™

I²C Mode is selected by the SEL pin = 1. In I²C Mode, each command is started as shown in Figure 3.8. Only the

number of bytes that is needed for the command must be sent. An exception is the HS-mode where 3 bytes must

always be sent as in SPI Mode. After the execution of a command (busy = 0), the expected data can be read as

illustrated in Figure 3.10 or if no data are returned by the command, the next command can be sent. The status

can be read at any time as described in Figure 3.9.

Figure 3.8 I²C™ Command Request

Command Request (I²C™ Write)

from master to slave

from slave to master

S

P

A

N

START condition

STOP condition

acknowledge

S

SlaveAddr

0

A

Command A P

write

0

CmdDat

<15:8>

CmdDat

<7:0>

S

SlaveAddr

A

Command

A

A P

not acknowledge

write

Figure 3.9 I²C™ Read Status

Read Status (I²C™ Read)

S

SlaveAddr

1

A

Status

N P

read

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ZSSC3027 Datasheet

Figure 3.10 I²C™ Read Data

Read Data (I²C™ Read)

(a) Example: after the completion of a Memory Read command

MemDat

<15:8>

MemDat

<7:0>

S

SlaveAddr

1

A

Status

A

N P

read

(b) Example: after the completion of a Full Measurement command (AC_HEX

)

BridgeDat

<15:8>

BridgeDat

<7:0>

TempDat

<15:8>

TempDat

<7:0>

S

SlaveAddr

1

A

Status

A

N P

read

All mandatory I²C-bus protocol features are implemented. Optional features like clock stretching, 10-bit slave

address, etc., are not supported by the ZSSC3027’s interface.

In I²C-High-Speed Mode, a command consists of a fixed length of three bytes.

3.6.

Memory

In the ZSSC3027, the memory is organized page-wise and can be programmed multiple (4) times (MTP). Each

register can only be programmed once per page. The valid page is determined by the page counter which can be

incremented with the command 5E_HEX– this leads to a “reset” of all registers and a re-programming is necessary.

Increasing the customer page counter will disable all old register contents of the former page. It is possible to

(re-)program a total of 4 pages. Resetting the page counter is not possible. The page counter starts with 0 and

can be incremented to a maximum of 3. If the 4^thmemory page has been used, no further changes in the memory

are possible – careful writing and page incrementing is strongly recommended. There are two MTP page types:

• Customer Page: Accessible by means of regular write operations (40_HEXto 57_HEX). It contains the customer

ID, interface setup data, measurement setup information, and calibration coefficients, etc.

• IDT Page:

Only accessible for write operations by IDT. The IDT page contains specific trim

information and is programmed during manufacturing test by IDT.

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ZSSC3027 Datasheet

3.6.1.

Programming Memory

Programming memory requires a specific supply voltage level (>2.9V) at the VDD pin (see section 1.3 for

specifications). The MTP programming voltage itself is generated by means of an implemented charge pump,

generating an internal memory programming voltage (VPP); no additional, external voltage, other than VDD

needed. The program timing is shown in Figure 3.11. Supplying the ZSSC3027 with VDD>2.9V during memory

programming is required. After the memory is programmed, it must be read again to verify the validity of the

memory contents.

Figure 3.11 Memory Program Operation

command

VPP

Start_CM

MemWr

MemRd

t_VPP

MemWr memory write customer address

MemRd memory read customer address

3.6.2.

Memory Status Commands

The 16-bit memory status answer for the commands 20_HEXto 37_HEXand 80_HEXto 8E_HEXcontains the following

information:

• One bit indicating if the data read was corrected.

• Two bits indicating the current page in use.

Table 3.7 Memory Status Word

Bit

Description

15 (MSB)

Data was corrected (0: no, 1: yes)

Current page

14

13

12:0

Undefined – do not use

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ZSSC3027 Datasheet

3.6.3.

Memory Contents

Table 3.8 MTP Memory Content Assignments

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

Customer ID byte 0 (combines with memory word

01_HEXto form customer ID)

00_HEX

15:0

0000_HEX

Cust_ID0

Customer ID byte 1 (combines with memory word

00_HEXto form customer ID)

01_HEX

Cust_ID1

Interface Configuration

I²C™ slave address; valid range: 00_HEXto 7F_HEX

(default: 00_HEX

)

6:0

8:7

000 0000_BINSlave_Addr

Note: address codes 04_HEXto 07_HEXare reserved for

entering the I²C™ High Speed Mode.

00_BIN

-

Reserved

Determines the polarity of the Slave Select pin (SS)

for SPI operation:

•

0  Slave Select is active low (SPI and

ZSSC3027 are active if SS==0)

9

0_BIN

SS_polarity

•

1  Slave Select is active high (SPI and

ZSSC3027 are active if SS==1)

02_HEX

Clock polarity and clock-edge select—determines

polarity and phase of SPI interface clock with the

following modes:

•

00  SCLK is low in idle state, data latch with

rising edge and data output with falling edge

11:10

15:12

00_BIN

CKP_CKE

01  SCLK is low in idle state, data latch with

falling edge and data output with rising edge

10  SCLK is high in idle state, data latch with

falling edge and data output with rising edge

11  SCLK is high in idle state, data latch with

rising edge and data output with falling edge

-

Not assigned

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April 20, 2016

ZSSC3027 Datasheet

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

Signal Conditioning Parameters

Bridge offset, bit[16]—functions as the MSB and

combines with Offset_B[15:0] in 05_HEXto form the

17-bit coefficient’s absolute value

0

1

2

3

0_BIN

Offset_B[16]

Sign for sensor bridge offset (Offset_B):

0 => a positive value or

0_BIN

Offset_B_sign

Gain_B[16]

1 => a negative value

Bridge gain, bit[16] —functions as the MSB and

combines with Gain_B[15:0] in 06_HEXto form the

17-bit coefficient’s absolute value

0_BIN

Sign of the sensor bridge gain (Gain_B):

0 => a positive value or

0_BIN

Gain_B_sign

1 => a negative value

1^st-order temperature coefficient of the bridge gain,

bit[16] —functions as the MSB and combines with

Tcg[15:0] in 07_HEXto form the 17-bit coefficient’s

absolute value

4

5

6

7

8

0_BIN

Tcg[16]

Sign of 1^st-order temperature coefficient (Tcg):

0 => a positive value or

Tcg_sign

Tco[16]

1 => a negative value

1^st-order temperature coefficient of the bridge offset,

bit[16] —functions as the MSB and combines with

Tco[15:0] in 08_HEXto form the 17-bit coefficient’s

absolute value

03_HEX

Sign of 1^st-order temperature coefficient (Tco):

0 => a positive value or

Tco_sign

SOT_tco[16]

1 => a negative value

2^nd-order temperature coefficient of the bridge offset,

bit[16] —functions as the MSB and combines with

SOT_tco[15:0] in 09_HEXto form the 17-bit

coefficient’s absolute value

Separate sign setting for 2^nd-order temperature

coefficient (SOT_tco):

9

0_BIN

SOT_tco_sign

SOT_tcg[16]

SOT_tcg_sign

0 => a positive value or

1 => a negative value

2^nd-order temperature coefficient of the bridge gain,

bit[16] —functions as the MSB and combines with

SOT_tcg[15:0] in 0A_HEXto form the 17-bit

coefficient’s absolute value

10

11

Separate sign setting for 2^nd-order temperature

coefficient (SOT_tcg):

0 => a positive value or

1 => a negative value

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April 20, 2016

ZSSC3027 Datasheet

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

2^nd-order coefficient of the bridge signal, bit[16] —

functions as the MSB and combines with

SOT_bridge[15:0] in 0B_HEXto form the 17-bit

coefficient’s absolute value

12

0_BIN

SOT_bridge[16]

Separate sign setting for 2^nd-order bridge coefficient

(SOT_bridge):

13

14

0_BIN

SOT_bridge_sign

SOT_curve

0 => a positive value or

1 => a negative value

Type of second-order curve correction for the bridge

sensor signal.

0_BIN

0  parabolic curve

1  s-shaped curve

Separate sign setting for T_SETL:

0 => a positive value or

15

0

0_BIN

TSETL_sign

Gain_T[16]

1 => a negative value

Temperature gain of temperature sensor, bit[16] —

functions as the MSB and combines with

Gain_T[15:0] in 0D_HEXto form the 17-bit coefficient’s

absolute value

0_BIN

Separate sign setting for the temperature gain

(Gain_T):

1

2

3

4

0_BIN

Gain_T_sign

SOT_T[16]

0 => a positive value or

1 => a negative value

2^nd-order temperature coefficient of temperature

sensor, bit[16] — functions as the MSB and

combines with SOT_T[15:0] in 0E_HEXto form the

17-bit coefficient’s absolute value

Separate sign setting for 2^nd-order temperature

coefficient (SOT_T):

04_HEX

SOT_T_sign

Offset_T[16]

0 => a positive value or

1 => a negative value

Temperature offset of temperature sensor, bit[16] —

functions as the MSB and combines with

Offset_T[15:0] in 0C_HEXto form the 17-bit

coefficient’s absolute value

Separate sign setting for the temperature offset

(Offset_T):

5

0_BIN

Offset_T_sign

-

0 => a positive value or

1 => a negative value

0000000000_BIN

15:6

Not assigned

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April 20, 2016

ZSSC3027 Datasheet

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

Bits [15:0] of the bridge offset correction coefficient,

which is an 18-bit wide absolute value (the

respective MSBs Offset_B[16] and sign,

Offset_B_sign, are under bits[1:0] in 03_HEX

)

Valid settings:

[-1/16 to 15/16] = 7000_HEX

[-2/16 to 14/16] = 6000_HEX

[-3/16 to 13/16] = 5000_HEX

[-4/16 to 12/16] = 4000_HEX

[-5/16 to 11/16] = 3000_HEX

[-6/16 to 10/16] = 2000_HEX

[-7/16 to 9/16] = 1000_HEX

[-8/16 to 8/16] = 0000_HEX

05_HEX

15:0

0000_HEX

Offset_B[15:0]

Bits[15:0] of 17-bit wide absolute value of the bridge

gain coefficient (the respective MSBs, Gain_B[16]

06_HEX

07_HEX

08_HEX

09_HEX

0A_HEX

0B_HEX

15:0

0000_HEX

Gain_B[15:0]

Tcg[15:0]

and sign, Gain_B_sign, are under bits[3:2] in 03_HEX

)

Coefficient for temperature correction of the bridge

gain term (the respective MSBs, Tcg[16] and sign,

Tcg_sign, are under bits[5:4] in 03_HEX

)

Coefficient for temperature correction of the bridge

Tco[15:0]

offset term (the respective MSBs, Tco[16] and sign,

Tco_sign, are under bits[7:6] in 03_HEX

)

2

^ndorder term applied to Tco (the respective MSBs,

SOT_tco[16] and sign, SOT_tco_sign, are under

bits[9:8] in 03_HEX

SOT_tco[15:0]

SOT_tcg[15:0]

SOT_bridge[15:0]

)

2

^ndorder term applied to Tcg (the respective MSBs,

SOT_tcg[16] and sign, SOT_tcg_sign, are under

bits[11:10] in 03_HEX

)

2^ndorder term applied to the sensor bridge readout

(the respective MSBs, SOT_bridge[16] and sign,

SOT_bridge_sign are under bits[13:12] in 03_HEX

)

Bits [15:0] of the temperature offset correction

coefficient (the respective MSBs, Offset_T[16] and

sign, Offset_T_sign, are under bits[5:4] in 04_HEX

)

Valid settings:

[-1/16 to 15/16] = 7000_HEX

[-2/16 to 14/16] = 6000_HEX

[-3/16 to 13/16] = 5000_HEX

[-4/16 to 12/16] = 4000_HEX

[-5/16 to 11/16] = 3000_HEX

[-6/16 to 10/16] = 2000_HEX

[-7/16 to 9/16] = 1000_HEX

[-8/16 to 8/16] = 0000_HEX

0C_HEX

15:0

0000_HEX

Offset_T[15:0]

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April 20, 2016

ZSSC3027 Datasheet

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

Bits [15:0] of the absolute value of the temperature

gain coefficient (the respective MSBs, Gain_T[16]

and sign, Gain_T_sign, are under bits[1:0] in 04_HEX

0D_HEX

15:0

0000_HEX

Gain_T[15:0]

)

2

^ndorder term applied to the temperature reading

(the respective MSBs, SOT_T[16] and sign,

SOT_T_sign, are under bits[3:2] in 04_HEX

0E_HEX

0F_HEX

15:0

0000_HEX

SOT_T[15:0]

T_SETL

)

Stores raw temperature reading at the temperature

at which low calibration points were taken

Measurement Configuration Register (BM_config)

Gain setting for the 1^stPREÀMP stage with

Gain_stage1:

•

00  12

01  20

10  30

11  40

1:0

00_BIN

Gain_stage1

Gain setting for the 2^ndPREAMP stage with

Gain_stage2:

•

000  1.1

001  1.2

010  1.3

011  1.4

100  1.5

101  1.6

110  1.7

111  1.8

4:2

000_BIN

Gain_stage2

10_HEX

Set up the polarity of the sensor bridge’s gain

(inverting of the chopper) with

5

0_BIN

Gain_polarity

•

0  positive (no polarity change)

1  negative (180° polarity change)

Absolute number of bits for the MSB conversion in

the ADC with Msb:

00_BIN

•

00  10-bit

01  12-bit

10  14-bit

11  16-bit

7:6

Msb

(11_BIN

)

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April 20, 2016

ZSSC3027 Datasheet

MTP

Address

Word / Bit

Range

Default

Setting

Description

Notes / Explanations

Absolute number of bits for the LSB conversion in

the ADC with Lsb:

•

00  0-bit (single-stage ADC)

01  2-bit

9:8

00_BIN

Lsb

10  4-bit

11  6-bit

ADC offset and resulting A2D input range [Vref] with

A2D_Offset:

•

000  1/16 results in range [-1/16, 15/16]

001  2/16 results in range [-2/16, 14/16

010  3/16 results in range [-3/16, 13/16]

011  4/16 results in range [-4/16, 12/16]

100  5/16 results in range [-5/16, 11/16]

101  6/16 results in range [-6/16, 10/16]

110  7/16 results in range [-7/16, 9/16]

111  8/16 results in range [-8/16, 8/16]

12:10

000_BIN

A2D_Offset

Selection between fixed ADC segmentations for

temperature measurements:

•

00  setup according to IDT-reserved memory

(recommended setup for best performance and

speed trade-off)

14:13

15

00_BIN

Temp_ADC

•

01  MSB=16, LSB=0 (16-bit)

10  MSB=10, LSB=6 (16-bit)

11  MSB=12, LSB=4 (16-bit)

0_BIN

-

Reserved

Customer Registers

11_HEX

12_HEX

13_HEX

14_HEX

15_HEX

16_HEX

Arbitrary customer use

Generated (checksum) for user page through a

linear feedback shift register (LFSR); signature is

checked with power-up to ensure memory content

integrity

17_HEX

15:0

-

ChecksumC

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April 20, 2016

ZSSC3027 Datasheet

The memory integrity checksum (referred to as CRC) is generated through a linear feedback shift register with the

polynomial:

g(x) = x¹⁶+ x¹⁵+ x²+ 1

with the initialization value: FFFF_HEX.

3.7. Calibration Sequence

Calibration essentially involves collecting raw signal and temperature data from the sensor-IC system for different

known bridge values and temperatures. This raw data can then be processed by the calibration master (assumed

to be a PC), and the calculated calibration coefficients can then be written to MTP memory. Below is a brief

overview of the steps involved in calibrating the ZSSC3027.

There are three main steps to calibration:

1. Assigning a unique identification to the ZSSC3027. This identification is written to shadow RAM and later

programmed in MTP memory. This unique identification can be stored in the two 16-bit registers

dedicated to customer ID. It can be used as an index into a database stored on the calibration PC. This

database will contain all the raw values of bridge readings and temperature readings for that part, as well

as the known bridge measurand conditions and temperature to which the bridge was exposed.

2. Data collection. Data collection involves getting uncorrected or raw data from the bridge at different

known measurand values and temperatures. Then this data is stored on the calibration PC using the

unique identification of the device as the index to the database.

3. Coefficient calculation and storage in MTP memory. After enough data points have been collected to

calculate all the desired coefficients, the coefficients can be calculated by the calibrating PC and written

to the shadow RAM. After that, MTP memory is programmed with the contents of the shadow RAM.

4. Result. The sensor signal and the characteristic temperature effect on output will be linearized according

to the setup-dependent maximum output range.

It is essential to perform the calibration with a fixed programming setup during the data collection phase. In order

to prevent any accidental misprocessing, it is further recommended to keep the MTP memory setup stable during

the whole calibration process as well as in the subsequent operation. A ZSSC3027 calibration only fits the single

setup used during its calibration. Changes of functional parameters after a successful calibration can decrease

the precision and accuracy performance of the ZSSC3027 as well as of the whole application.

3.7.1.

Calibration Step 1 – Assigning Unique Identification

Assign a unique identification number to the ZSSC3027 by using the memory write command (40_HEXfollowed by

two bytes of identification data and 41_HEXfollowed by two bytes of identification data; see Table 3.1 and Table 3.8)

to write the identification number to Cust_ID0 at memory address 00_HEXand Cust_ID1 at address 01_HEXas

described in section 3.6.1. These two 16-bit registers allow for more than 4 trillion unique devices.

3.7.2.

Calibration Step 2 – Data Collection

The number of unique points (measurand and/or temperature) at which calibration must be performed generally

depends on the requirements of the application and the behavior of the resistive bridge in use. The minimum

number of points required is equal to the number of bridge coefficients to be corrected with a minimum of three

different temperatures at three different bridge values. For a full calibration resulting in values for all 7 possible

bridge coefficients and 3 possible temperature coefficients, a minimum of 7 pairs of bridge with temperature

measurements must be collected.

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April 20, 2016

ZSSC3027 Datasheet

Within this minimum 3x3 measurements field, data must be collected for the specific value pairs (at known

conditions) and then processed to calculate the coefficients. In order to obtain the potentially best and most robust

coefficients, it is recommended that measurement pairs (temperature vs. measurand) be collected at the outer

corners of the intended operation range or at least at points that are located far from each other. It is also

essential to provide highly precise reference values as nominal, expected values.

Note: The measurement precision of the external calibration-measurement equipment should be ten times more

accurate than the expected ZSSC3027 output precision after calibration in order to avoid precision losses caused

by the nominal reference values (e.g., measurand signal and temperature deviations).

Note: An appropriate selection of measurement pairs can significantly improve the overall system performance.

The determination of the measurand-related coefficients will use all of the measurement pairs. For the

temperature-related correction coefficients, three of the measurement pairs (at three different temperatures) will

be used.

Note: There is an inherent redundancy in the 7 bridge-related and 3 temperature-related coefficients. Since the

temperature is a necessary output (which also needs correction), the temperature-related information is

mathematically separated, which supports faster and more efficient DSP calculations during the normal usage of

the sensor-IC system.

The recommended approach for data collection is to make use of the raw-measurement commands:

• For bridge sensor values:

•

A2_HEX+ 0000_HEX

:

Single bridge measurement for which the configuration register will be loaded

from the BM_Config register (10_HEXin MTP); preprogramming the measurement

setup in the MTP is required.

A3_HEX+ ssss_HEX

:

Single bridge measurement for which the BM_Config configuration register

(Gain, ADC, Offset, etc.) will be loaded as ssss_HEX, which is sent as the data

following the A3_HEXcommand.

• For temperature values (grey text indicates values that are possible but will overwrite IDT settings):

•

A6_HEX+ 0000_HEX

:

Single temperature measurement for which the configuration register will be

loaded from an internal temperature configuration register (preprogrammed by

IDT in MTP); preprogramming of the respective configuration is done by IDT prior

to IC delivery. This is the recommended approach for temperature data

collection.

A7_HEX+ ssss_HEX

:

Single temperature measurement for which the configuration register (Gain,

ADC, Offset, etc.) will be loaded as ssss_HEXand must be provided externally via

the interface. The data composition of the temperature configuration register is

similar to the BM_config (address 10_HEX) register for the bridge sensor.

3.7.3.

Calibration Step 3 – Coefficient Calculations

The math to perform the coefficient calculation is complicated and will not be discussed in detail. There is a brief

overview in the next section. IDT will provide software (DLLs) to perform the coefficient calculation (external to the

sensor-IC system) based on auto-zero corrected values. After the coefficients are calculated, the final step is to

write them to the MTP memory of the ZSSC3027.

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April 20, 2016

ZSSC3027 Datasheet

3.8. The Calibration Math

3.8.1.

Bridge Signal Compensation

The saturation check in the ZSSC3027 is enhanced compared with older SSCs from IDT. Even saturation effects

of the internal calculation steps are detected, allowing the final correction output to still be determined. It is

possible to get potentially useful signal conditioning results even if there has been an intermediate saturation

during the calculations – these cases are detectable by observing the status bit[0] for each measurement result.

Details about the saturation limits and the valid ranges for values are provided in the following equations.

SOT_curve selects whether second-order equations compensate for sensor nonlinearity with a parabolic or

S-shaped curve. The parabolic compensation is recommended.

The correction formula for the differential signal reading is represented as a two-step process depending on the

SOT_curve setting.

Equations for the parabolic SOT_curve setting (SOT_curve = 0):

Simplified equations:

∆T = T _ Raw −T_SETL

(1)

(2)

∆T SOT_tcg









K₁= 2¹⁵+

⋅

⋅∆T +Tcg



2¹⁵



∆T SOT_tco







K₂= Offset_ B + BR _ Raw+

⋅

⋅∆T +Tco





(3)

(4)

(5)

2¹⁵



K₁

2¹⁵

Gain _ B

(delimited to positive number range)

Z_BP

=

⋅

⋅ K₂+ 2¹⁵

2¹⁵

Z_BP

SOT_ bridge









B

=

⋅

⋅ Z _BP+ 2¹⁵

2¹⁵





Where

B

=

Corrected bridge reading output via I²C™ or SPI; range [0_HEXto FFFF_HEX

Raw bridge reading from ADC after AZ correction; range [-1FFFF_HEXto 1FFFF_HEX

Bridge gain term; range [-1FFFF_HEXto 1FFFF_HEX

Bridge offset term; range [-1FFFF_HEXto 1FFFF_HEX

Temperature coefficient gain term; range [-1FFFF_HEXto 1FFFF_HEX

Temperature coefficient offset term; range [-1FFFF_HEXto 1FFFF_HEX

]

BR_Raw

=

]

Gain_B

Offset_B

Tcg

]

Tco

]

T_Raw

Raw temperature reading after AZ correction; range [-1FFFF_HEXto 1FFFF_HEX

]

T_SETL

T_Raw reading at which low calibration was performed (e.g., 25°C);

range [-FFFF_HEXto FFFF_HEX

]

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April 20, 2016

ZSSC3027 Datasheet

SOT_tcg

SOT_tco

=

Second-order term for Tcg non-linearity; range [-1FFFF_HEXto 1FFFF_HEX

Second-order term for Tco non-linearity; range [-1FFFF_HEXto 1FFFF_HEX

]

SOT_bridge = Second-order term for bridge non-linearity; range [-1FFFF_HEXto 1FFFF_HEX

]

Z_BPIntermediary term

=

Complete equations:

2

¹⁷−1

(6)

(7)

∆T =

[

T _ Raw −T_SETL

]

−2¹⁷

2

¹⁷−1

2

¹⁷−1











²

¹⁷−1











²



∆T

2

SOT_tcg

15

K = 2 +

⋅ 

⋅∆T

+Tcg



1

15

2¹⁵





17

₋₂









17

₋₂





17

₋₂





17

₋₂

2

¹⁷−1

2

¹⁷−1









2

¹⁷−1











²



¹⁷−1









²



∆T

2

SOT_tco



K = Offset_ B + BR _ Raw +

⋅

⋅∆T

+Tco

(8)

(9)



2

15

2¹⁵









17

₋₂









17

₋₂







17



₋₂



17



₋₂



17



₋₂

¹⁷−1



²

2

¹⁷−1



²









K

Gain _ B







=

⋅

+ 2¹⁵

1



Z_BP

⋅ K₂

15

2¹⁵

2

17









₋₂

17

₋₂





₀

2

¹⁶−1

¹⁷−1

²



¹⁷−1









²



Z

SOT_ bridge

B

=

⋅

⋅ Z _BP

+ 2¹⁵

(10)



BP

15



2

2¹⁵







17

₋₂







17

₋₂







₀

Where

= absolute value

= bound/saturation number range from ll to ul; over/under-flow is reported as saturation in status byte



ul

ll

[



]

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April 20, 2016

ZSSC3027 Datasheet

Equations for the S-shaped SOT_curve setting (SOT_curve = 1):

Simplified equations:

K₁

Gain _ B

Z_BS

=

⋅

⋅ K₂

(11)

(12)

2¹⁵

Z_BS

SOT_ bridge







⋅ Z _BS+ 2¹⁵+ 2¹⁵

(delimited to positive number range)

B

=

⋅



2¹⁵





Complete equations:

2

¹⁷−1







K

Gain _ B



²



1

15



Z_BS

=

⋅

⋅ K₂

(13)

(14)

2¹⁵

2

17





₋₂





17

₋₂

16

²



2

¹⁷−1



²



¹⁷−1











²



Z

SOT_ bridge

B

=

⋅ Z _BS

+ 2¹⁵

BS

15



⋅



2¹⁵







17

2

₋₂







17

₋₂







17

₋₂





₀



41

April 20, 2016

ZSSC3027 Datasheet

3.8.2.

Temperature Signal Compensation

Temperature is measured internally. Temperature correction contains both linear gain and offset terms as well as

a second-order term to correct for any nonlinearities. For temperature, second-order compensation for non-

linearity is always parabolic. Again, the correction formula is best represented as a two-step process as follows:

Simplified equations:

Gain _T

(delimited to positive number range)

Z_T=

⋅

(

T _ Raw + Offset _T

+ 2¹⁵

)

(15)

(16)

2¹⁵

Z_T

SOT_T

2¹⁵









⋅ Z_T+ 2¹⁵

(delimited to positive number range)

T

=

⋅

2¹⁵





Complete equations:

¹⁷−1

²

¹⁷−1



₋₁²



2¹⁷

Gain _T

Z_T= 

⋅

[

T _ Raw + Offset _T

]

+ 2¹⁵

(17)

(18)

−2¹⁷

2¹⁵







17

₋₂







₀

2

¹⁶−1

¹⁷−1

²



¹⁷−1











²





Z

SOT_T

2¹⁵

+ 2¹⁵

T

15



T

=

⋅

⋅ Z _T







17

2

₋₂







17

₋₂







₀

Where

Gain_T

T_Raw

=

Gain coefficient for temperature; range [-1FFFF_HEXto 1FFFF_HEX

Raw temperature reading after AZ correction; range [-1FFFF_HEXto 1FFFF_HEX

Offset coefficient for temperature; range [-1FFFF_HEXto 1FFFF_HEX

Second-order term for temperature source non-linearity; range [-1FFFF_HEXto 1FFFF_HEX

]

=

]

Offset_T

]

SOT_T

]

ul

ll

=

bound/saturation number range from ll to ul; over/under-flow is reported as saturation in

[ ]



status byte

42

April 20, 2016

ZSSC3027 Datasheet

4 Die Pad Assignments

The ZSSC3027 is available in die form. See Figure 4.1 for pad assignments.

Note that the ZMDI-test pads are for IDT use only.

Figure 4.1 ZSSC3027 Pad Assignments

Table 4.1 Pad Assignments

Name

VDD

VSS

Direction

IN

Type

Supply

Analog

Digital

Description

IC positive supply voltage for the ZSSC3027; regular bond pad

Ground reference voltage signal

Positive bridge supply

IN

VDDB

INN

OUT

IN

Negative bridge signal

EOC

OUT

End of conversion; regular bond pad

43

April 20, 2016

ZSSC3027 Datasheet

Name

MISO

Direction

Type

Digital

Analog

Digital

-

Description

OUT

IN

Data output for SPI

SCLK/SCL

MOSI/SDA

VSSB

Clock input for I²C™/SPI

Data input for SPI; data in/out for I²C™

Negative bridge supply (bridge sensor ground)

Positive bridge signal

IN/Out

OUT

IN

INP

SEL

IN

I²C™ or SPI interface select

Slave select for SPI

SS

IN

ZMDI-test

-

Do not connect to these pads

5 Quality and Reliability

The ZSSC3027 is available in a standard qualification version. For the standard version ZSSC3027CCxxx, all

data specified parameters are guaranteed if not stated otherwise.

6 Ordering Sales Codes

Sales Code

Description

Package

ZSSC3027AC1B

ZSSC3027AC6B

ZSSC3027AC7B

ZSSC3026-KIT

Die—temperature range: –40°C to +85 °C

Die—temperature range: –40°C to +85°C

Wafer (304µm) unsawn, tested

Wafer (725µm) unsawn, tested

Wafer (200µm) unsawn, tested

Evaluation Kit for ZSSC3026, including boards, cable, software, and 1 ZSSC3026 PQFN24 sample.

The ZSSSC3026 is equivalent to the ZSSC3027. IDT recommends using the ZSSC3026 Evaluation Kit

to evaluate the capabilities of the ZSSC3027 because the ZSSC3027 is only available as die.

Contact IDT Sales for additional information.

44

April 20, 2016

ZSSC3027 Datasheet

7


型号：	ZSSC3027AC6B
厂家：	RENESAS TECHNOLOGY CORP
描述：	Low-Power, High-Resolution 16-Bit Sensor Signal Conditioner
文件：	总47页 (文件大小：905K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

ZSSC3027AC6B [RENESAS]

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