AD8251ARZ-R7 [ADI]

12MHz 20V/us G=1,2,4,8 Programmable Gain iCMOS Instrumentation Amplifier; 12MHz的20V / us的G = 1,2,4,8可编程增益的iCMOS仪表放大器


型号：	AD8251ARZ-R7
厂家：	ADI
描述：	12MHz 20V/us G=1,2,4,8 Programmable Gain iCMOS Instrumentation Amplifier 12MHz的20V / us的G = 1,2,4,8可编程增益的iCMOS仪表放大器仪表放大器放大器电路光电二极管
文件：	总8页 (文件大小：124K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

12MHz 20V/μs G=1,2,4,8 Programmable

Gain

CMOS™ Instrumentation Amplifier

Preliminary Technical Data

AD8251

FEATURES

Easy to Use

GENERAL DESCRIPTION

Programmable Gains: 1, 2, 4, 8

Digital or Pin Programmable Gain Setting

Temp Range -40°C to 85°C

The AD8251 is a digitally gain programmable

instrumentation amplifier that has high GΩ input

impedance and low distortion making it suitable for sensor

interfacing and driving high sample rate analog to digital

converters. It has high bandwidth of 12MHz, low distortion

and settle time of 0.5us to 0.01%. Offset drift and gain drift

are limited to 1uV/°C and 10ppm/°C respectively. In

addition to its wide input common-voltage range, it boasts a

high common-mode rejection of 80dB at G=1 from DC to

50kHz. The combination of precision DC performance

coupled with high speed capabilities make the AD8251 an

excellent candidate for data acquisition and medical

applications. Furthermore, this monolithic solution

simplifies design, manufacturing and boosts performance of

instrumentation by maintaining tight match of internal

resistors and amplifiers.

EXCELLENT DC PERFORMANCE

High CMRR 98dB G=8

Low Gain Drift: 10ppm/°C

Low Offset Drift: 1uV/°C

Low Offset: 75uV G=8

EXCELLENT AC PERFORMANCE

Fast Settle Time: 0.5us to 0.01%

High Slew Rate: 20V/μs

High CMRR over Frequency: 80dB to 50kHz

Low Noise: 13nV√Hz, G=8

Low Power: 3.5 mA (typ)

Supply: ±5V to ±12V

The AD8251’s user interface comprises of a parallel port that

allows users to set the gain in one of three different ways. A

two bit word sent to A1 and A2, via a bus may be latched

Applications

Data Acquisition

Bio-Medical Analysis

Test and Measurement

High Performance System Monitoring

using the

input. An alternative is to set the gain within

1μs by using the gain port in transparent mode where the

state of A0 and A1 directly set the gain. The last method is

to strap A1 and A2 to a high or low voltage potential,

permanently setting the gain.

DGD

Logic

-IN

The AD8251 is available in a 10 pin MSOP package and

specified over -40°C to 85°C, making it an excellent solution

for applications where size and packing density are

important considerations.

OUT

+IN

AD8251

+VS

-VS

REF

Figure 1. Functional Block Diagram

Rev.PrB

Information furnished by Analog Devices is believed to be accurate and reliable.

However, no responsibility is assumed by Analog Devices for its use, nor for any

infringements of patents or other rights of third parties that may result from its use.

Specifications subject to change without notice. No license is granted by implication

or otherwise under any patent or patent rights of Analog Devices. Trademarks and

registered trademarks are the property of their respective companies.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700

Fax: 781.326.8703

www.analog.com

AD8251

Preliminary Technical Data

TABLE OF CONTENTS

AD8251—Specifications.................................................................. 3

Transparent Gain Setting Mode: .................................................5

Write Enable Gain Setting Mode:................................................5

Outline Dimensions..........................................................................5

ESD Caution...................................................................................5

Preliminary Revision : B

Timing Diagram ........................................................................... 5

Absolute Maximum Ratings............................................................ 5

Pin Configurations And Functional Descriptions ....................... 5

REVISION HISTORY

Rev. PrB | Page 2 of 8

Preliminary Technical Data

AD8251

AD8251—SPECIFICATIONS

Table 1. V_S= 12 V, V_REF= 0 V (@T_A= 25^oC, G = +1, R_L= 2 kΩ, unless otherwise noted.)

AD8251ARM

Typ Max

Parameter

Conditions

Min

Unit

COMMON-MODE REJECTION RATIO

(CMRR)

CMRR to 60 Hz with 1 kΩ Source

Imbalance

V_CM= -10 V to +10 V

G = 1

G = 2

G = 4

G = 8

CMRR to 50kHz

V_CM= -10 V to +10 V

G = 1

G = 2

G = 4

G = 8

NOISE

Voltage Noise, 1kHz

G=1

G=2

G=4

G=8

G=1

G=2

G=4

G=8

nV/√Hz

ꢀV p-p

fA/√Hz

RTI, 0.1 Hz to 10 Hz

Current Noise

VOLTAGE OFFSET

Offset, V_OS

f = 1kHz

G=1, V_S= ±5 V to ±12 V

T = -40°C to +85°C

G=2, V_S= ±5 V to ±12 V

T = -40°C to +85°C

G=4, V_S= ±5 V to ±12 V

T = -40°C to +85°C

G=8, V_S= ±5 V to ±12 V

T = -40°C to +85°C

250

150

100

μV

Over Temperature

Average TC

μV

μV/°C

μV

Offset, V_OS

Over Temperature

Average TC

μV

μV/°C

μV

Offset, V_OS

Over Temperature

Average TC

μV

μV/°C

μV

Offset, V_OS

Over Temperature

Average TC

μV

μV/°C

Offset Referred to the Input vs.

Supply (PSR)

V_S= ±8 V to ±12 V

G = 1

G = 2

G = 4

G = 8

115

110

INPUT CURRENT

Input Bias Current

Over Temperature

T = -40°C to +85°C

Rev. PrB| Page 3 of 8

AD8251

Preliminary Technical Data

AD8251ARM

Parameter

Conditions

Min

Typ Max

Unit

Average TC

pA/°C

Input Offset Current

Over Temperature

Average TC

T = -40°C to +85°C

1.5

pA/°C

DYNAMIC RESPONSE

Small Signal -3dB Bandwidth

MHz

G=1

G=2

G=4

G=8

Settling Time 0.01%

10 V Step

G=1

0.5

μS

G=2

G=4

G=8

Settling Time 0.001%

10 V Step

G=1

1.5

μS

G=2

G=4

G=8

Slew Rate

G=1

G=2

G=4

G=8

V/μS

Total Harmonic Distortion +

Noise

RL = 100kOhms, G=1

RL = 2kOhms, G=1

GAIN

Gain Range: 1, 2, 4, 8

Gain Error

V/V

V_OUT= ±10 V

G=1

0.05

G=2

G=4

G=8

Gain Nonlinearity

V_OUT= –10 V to +10 V

G=1, R_L= 10 kΩ

G=2, R_L= 10 kΩ

G=4, R_L= 10 kΩ

G=8, R_L= 10 kΩ

G=1-8, R_L= 2 kΩ

All Gains

ppm

Gain Nonlinearity

Gain vs. Temperature

ppm

ppm/°C

INPUT

Input Impedance

Differential

1|| 2

GΩ|| pF

Common Mode

+Vs

1.5

Input Operating Voltage Range

Over Temperature

V_S= ±5 V to ±12 V

T = -40°C to +85°C

-Vs + 1

Rev. PrB | Page 4 of 8

Preliminary Technical Data

AD8251

AD8251ARM

Typ Max

Parameter

Conditions

Min

Unit

OUTPUT

R_L= 10 kΩ,

–Vs +

1.5

+Vs –

1.5

Output Swing

V_S= ±5 V to ±12 V

T = -40°C to +85°C

Over Temperature

Short Circuit Current

REFERENCE INPUT

R_IN

kΩ

μA

I_IN

V_IN+, V_IN–, V_REF= 0

–Vs

+Vs

Voltage Range

Gain to Output

V/V

Digital Logic Inputs

Digital Ground Voltage, DGND

Digital Input Voltage Low

Digital Input Voltage High

Digital Input Leakage Current

Gain Switching Time

T_SU

Referenced to DGND

T_HD

T_{WR_LO}

T_{WR_HI}

POWER SUPPLY

Operating Range³

Quiescent Current

Over Temperature

TEMPERATURE RANGE

Specified Performance

±5

±12

3.5

T = -40°C to +85°C

–40

+85

°C

TIMING DIAGRAM

WR-LO

WR-HI

A0, A1

Figure 2.Timing Diagram

Rev. PrB| Page 5 of 8

AD8251

Preliminary Technical Data

ABSOLUTE MAXIMUM RATINGS

Board)

Table 2. AD8251 Absolute Maximum Ratings

Package Glass Transition

Temperature

°C

Parameter

Rating

ESD (Human Body Model)

ESD (Charge Device Model)

ESD (Machine Model)

Supply Voltage

+/-14V

Power Dissipation

See Figure 2

Output Short Circuit Current

Common-Mode Input Voltage

Differential Input Voltage

Storage Temperature

Operating Temperature Range

-Vs – 0.5 V to +Vs + 0.5 V

Stresses above those listed under Absolute Maximum Ratings

may cause permanent damage to the device. This is a stress

rating only and functional operation of the device at these or

any other condition s above those indicated in the operational

section of this specification is not implied. Exposure to absolute

maximum rating conditions for extended periods may affect

device reliability.

–65°C to +125°C

–40°C to +85°C

°C

Lead Temperature Range

(Soldering 10 sec)

Junction Temperature

°C

Θ_JA(4 layer JEDEC Standard

°C/W

Rev. PrB | Page 6 of 8

Preliminary Technical Data

AD8251

PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS

TRANSPARENT GAIN SETTING MODE:

-IN

DGND

-VS

10 +IN

VREF

In this mode, the gain is set by toggling A0 and A1 to HIGH or

LOW. To enable transparent mode, tie to –Vs. This

AD8251

+VS

TOP VIEW

(Not to Scale)

VOUT

configures the AD8251 to change gains when A0 and A1 are set

according to Table 4.

NC = NO CONNECT

Table 4. . Transparent Mode Gain Settings

Figure 3. 10-Lead MSOP

WR A1 A0

-Vs LO LO

-Vs LO HI

-Vs HI LO

-Vs HI HI

WRITE ENABLE GAIN SETTING MODE:

In this mode, the gains are changed only during the negative

edge of the

strobe. So for instance, the gain is determined

by the two bit value held on A0 and A1 at the time the

strobe transitions from HIGH to LOW.

Table 3. Pin Function Descriptions—

10-Lead MSOP(ARM PACKAGE)

Pin No.

Name

Description

WR-LO

WR-HI

-IN

Inverting Input Terminal (True

differential input)

DGND

-Vs

Digital Ground.

Negative Supply Terminal

Gain Setting Pin (LSB)

Gain Setting Pin (MSB)

Write Enable

A0, A1

Table 5. : Write Enable Mode Gain Settings

Gain (changes to) WR A1 A0

VOUT

+Vs

VREF

Output Terminal

Positive Supply Terminal

Reference Voltage Terminal (drive this

pin with a low impedance voltage

source to level shift the output signal)

HI -> LO LO LO

HI -> LO LO HI

HI -> LO HI LO

HI -> LO HI HI

+IN

Non-inverting Input Terminal (True

differential input)

No Change

X = don’t care

LO->LO

LO->HI

HI-> HI

GAIN SETTING

The AD8251’s gains are set digitally. The A0 and A1 pins must

be set either HIGH or LOW with respect to digital ground,

DGND. The

pin is a tri-state switch. It may be set to one of

three levels, HIGH, LOW or to –VS. A HIGH signal is typically

greater than 4V but less than 6V and a LOW signal is typically

less than 1V but higher than DGND, 0V. Gains can be

programmed using the following methods:

Rev. PrB| Page 7 of 8

AD8251

Preliminary Technical Data

OUTLINE DIMENSIONS

3.10

3.00

2.90

5.15

4.90

4.65

3.10

3.00

2.90

PIN 1

0.50 BSC

0.95

0.85

0.75

1.10 MAX

0.80

0.60

0.40

8°

0°

0.15

0.05

0.33

0.17

SEATING

PLANE

0.23

0.08

COPLANARITY

0.10

COMPLIANT TO JEDEC STANDARDS MO-187-BA

Figure 4. 10 Lead MSOP (RM) – Dimensions shown in millimeters

ESD CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the

human body and test equipment and can discharge without detection. Although this product features

proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy

electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance

degradation or loss of functionality.

Table 6. Ordering Guide

AD00000 Products

Temperature Package

Package Description

10-Lead MSOP

Package Option

RM-10

Branding

AD8251ARZ

–40°C to +85°C

AD8251ARZ-RL

AD8251ARZ-R7

AD8251-EVAL

–40°C to +85°C

10-Lead MSOP

RM-10

–40°C to +85°C

10-Lead MSOP

RM-10

Evaluation Board

Rev. PrB | Page 8 of 8

AD8251ARZ-R7 [ADI]

相关型号：

AD8251ARZ-RL

AD8251_07

AD8253

AD8253-EVALZ

AD8253-EVALZ1

AD8253ARMZ

AD8253ARMZ-R7

AD8253ARMZ-R71

AD8253ARMZ-RL

AD8253ARMZ-RL1

AD8253ARMZ1

AD8253_08