ADM1023ARQ-REEL [ROCHESTER]
SPECIALTY ANALOG CIRCUIT, PDSO16, MO-137AB, QSOP-16;
| 型号： | ADM1023ARQ-REEL |
| 厂家： | 
Rochester Electronics |
| 描述： | SPECIALTY ANALOG CIRCUIT, PDSO16, MO-137AB, QSOP-16 光电二极管 |
| 文件： | 总21页 (文件大小：1266K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
ACPI-Compliant, High Accuracy
Microprocessor System Temperature Monitor
ADM1023
FEATURES
GENERAL DESCRIPTION
The ADM10231 is a 2-channel digital thermometer and under-
and overtemperature alarm for use in personal computers and
other systems requiring thermal monitoring and management.
Optimized for the Pentium® III, the higher accuracy allows
Next generation upgrade of ADM1021
On-chip and remote temperature sensing
Offset registers for system calibration
1°C accuracy and resolution on local channel
0.125°C resolution/1°C accuracy on remote channel
Programmable over/under temperature limits
Programmable conversion rate
systems designers to safely reduce temperature guard banding
and increase system performance. The device can measure the
temperature of a microprocessor using a diode-connected PNP
transistor, which may be provided on-chip with the Pentium III
or similar processors; or it can be a low-cost, discrete NPN/PNP
device such as the 2N3904/2N3906. A novel measurement
technique cancels out the absolute value of the transistor’s base
emitter voltage so that no calibration is required. The second
measurement channel measures the output of an on-chip
temperature sensor to monitor the temperature of the device
and its environment.
ALERT
Supports system management bus (SMBus)
2-wire SMBus serial interface
200 μA max operating current (0.25 conversions/second)
1 μA standby current
3 V to 5.5 V supply
Small 16-lead QSOP package
APPLICATIONS
The ADM1023 communicates over a 2-wire serial interface
compatible with SMBus standards. Under- and overtemperature
limits can be programmed into the device over the serial bus,
Desktop computers
Notebook computers
Smart batteries
ALERT
and an
temperature is out of range. This output can be used as an
ALERT
output signals when the on-chip or remote
Industrial controllers
Telecomm equipment
Instrumentation
interrupt or as an SMBus
.
FUNCTIONAL BLOCK DIAGRAM
ADDRESS POINTER
REGISTER
ONE-SHOT
REGISTER
CONVERSION RATE
REGISTER
OFFSET
REGISTERS
ON-CHIP
TEMPERATURE
SENSOR
LOCAL TEMPERATURE
LOW-LIMIT REGISTER
LOCAL TEMPERATURE
VALUE REGISTER
LOCAL TEMPERATURE
LOW-LIMIT COMPARATOR
LOCAL TEMPERATURE
HIGH-LIMIT COMPARATOR
LOCAL TEMPERATURE
HIGH-LIMIT REGISTER
3
4
D+
D–
A-TO-D
CONVERTER
ANALOG
MUX
REMOTE TEMPERATURE
LOW-LIMIT COMPARATOR
REMOTE TEMPERATURE
LOW-LIMIT REGISTERS
BUSY RUN/STANDBY
REMOTE TEMPERATURE
HIGH-LIMIT COMPARATOR
REMOTE TEMPERATURE
VALUE REGISTERS
REMOTE TEMPERATURE
HIGH-LIMIT REGISTERS
CONFIGURATION
REGISTER
15
11
STBY
EXTERNAL DIODE OPEN-CIRCUIT
INTERRUPT
MASKING
ALERT
STATUS REGISTER
ADM1023
SMBus INTERFACE
1
2
5
7
8
9
13
16
12
14
10
6
NC
V
NC GND GND NC
NC
NC
SDATA
SCLK
ADD0
ADD1
DD
NC = NO CONNECT
Figure 1.
1 Protected by U.S. Patents 5,195,827; 5,867,012; 5,982,221; 6,097,239; 6,133,753; 6,169,442; other patents pending.
Rev. H
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 owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
© 2005 Analog Devices, Inc. All rights reserved.
ADM1023
TABLE OF CONTENTS
Specifications..................................................................................... 3
Serial Bus Interface..................................................................... 12
Address Pins................................................................................ 12
Absolute Maximum Ratings............................................................ 4
Thermal Characteristics .............................................................. 4
ESD Caution.................................................................................. 4
Pin Configuration and Function Description .............................. 5
Typical Performance Characteristics ............................................. 6
Theory of Operation ........................................................................ 8
Functional Description................................................................ 8
Measurement Method.................................................................. 9
ALERT
Output............................................................................ 14
Low Power Standby Modes....................................................... 15
Sensor Fault Detection .............................................................. 15
Applications..................................................................................... 16
Factors Affecting Accuracy....................................................... 16
Layout Considerations............................................................... 16
Application Circuits................................................................... 17
Outline Dimensions....................................................................... 18
Ordering Guide .......................................................................... 18
Sources of Errors on Thermal Transistors Measurement
Method........................................................................................... 9
Temperature Data Format......................................................... 10
Register Functions...................................................................... 10
REVISION HISTORY
7/05—Rev. G to Rev. H
9/02—Rev. C to Rev. D
Changes to Table 1.............................................................................3
Outline Dimensions updated...........................................................13
2/05—Rev. F to Rev. G
5/02—Rev. B to Rev. C
Updated Format.................................................................. Universal
Changes to Specifications.................................................................3
Changes to Absolute Maximum Ratings........................................4
Changes to Figure 14.........................................................................8
Changes to Figure 21.......................................................................17
Changes to Ordering Guide ...........................................................18
Figures 2 to 11 changed to TPCs 1–10, renumbered figures
accordingly .........................................................................................4
Text change to Figure 9 (TPC 8)......................................................5
Callouts in text added for Tables IV–VI.........................................8
Change to Serial Bus Interface section ...........................................9
4/00—Revision 0: Initial Version
4/03—Rev. E to Rev. F
Added Reference to Figure 1............................................................2
4/03—Rev. D to Rev. E
Added ESD Caution ..........................................................................3
Updated Outline Dimensions........................................................13
Rev. H | Page 2 of 20
ADM1023
SPECIFICATIONS
TA = TMIN to TMAX1, VDD = 3.0 V to 3.6 V, unless otherwise noted.
Table 1.
Parameter
Min
Typ
Max Unit Test Conditions/Comments
POWER SUPPLY AND ADC
Temperature Resolution, Local Sensor
Temperature Resolution, Remote Sensor
Temperature Error, Local Sensor
1
°C
°C
Guaranteed no missed codes
Guaranteed no missed codes
TA = 60°C to 100°C
0.125
−1.5
−3
−1
−3
0.5 +1.5 °C
1
+3
+1
+3
°C
°C
°C
TA = 0°C to 120°C
Temperature Error, Remote Sensor
TA, TD = 60°C to 100°C2
TA, TD = 0°C to 120°C2
TA = 60°C to 100°C
Relative Accuracy
Supply Voltage Range3
0.25 °C
3
2.55
3.6
2.8
V
V
mV
V
mV
μA
μA
μA
μA
ms
Undervoltage Lockout Threshold
Undervoltage Lockout Hysteresis
Power-On Reset Threshold
POR Threshold Hysteresis
Standby Supply Current
2.7
25
1.7
50
VDD input, disables ADC, rising edge
VDD, falling edge4
0.9
2.2
5
1
4
VDD = 3.3 V, no SMBus activity
SCLK at 10 kHz
0.25 conversions/sec rate
2 conversions/sec rate
From stop bit to conversion complete
(both channels) D+ forced to D− + 0.65 V
Average Operating Supply Current
Autoconvert Mode, Averaged Over 4 Sec
Conversion Time
130
225
115
200
370
170
65
Remote Sensor Source Current
120
7
205
12
0.7
50
300
16
μA
μA
V
High level4
Low level4
D-Source Voltage
Address Pin Bias Current (ADD0, ADD1)
SMBus INTERFACE
μA
Momentary at power-on reset
See Figure 3
Logic Input High Voltage, VIH
STBY, SCLK, SDATA
2.2
V
V
VDD = 3 V to 5.5 V
Logic Input Low Voltage, VIL
STBY, SCLK, SDATA
0.8
VDD = 3 V to 5.5 V
SMBus Output Low Sink Current
6
1
mA
mA
μA
pF
kHz
μs
μs
μs
μs
μs
SDATA forced to 0.6 V
ALERT
forced to 0.4 V
ALERT
Output Low Sink Current
Logic Input Current, IIH, IIL
SMBus Input Capacitance, SCLK, SDATA
SMBus Clock Frequency
SMBus Clock Low Time, tLOW
SMBus Clock High Time, tHIGH
SMBus Start Condition Setup Time, tSU:STA
SMBus Start Condition Hold Time, tHD:STA
SMBus Stop Condition Setup Time, tSU:STO
SMBus Data Valid to SCLK Rising Edge Time, tSU:DAT
SMBus Bus Free Time, tBUF
−1
+1
5
400
1.3
0.6
0.6
0.6
0.6
100
1.3
tLOW between 10% points
tHIGH between 90% points
Time from 10% of SDATA to 90% of SCLK
Time from 90% of SCLK to 10% of SDATA
Time for 10% or 90% of SDATA to 10% of SCLK
Between start/stop condition
Master clocking in data
ns
μs
ns
ns
SCLK SDATA Rise Time, tR MAX
SCLK SDATA Fall Time, tF MAX
300
300
VDD = 0 V
1 TMAX = 120°C, TMIN = 0°C.
2 TD is the temperature of the remote thermal diode; TA, TD = 60°C to 100°C.
3 Operation at VDD = 5 V guaranteed by design; not production tested.
4 Guranteed by design; not production tested.
Rev. H | Page 3 of 20
ADM1023
ABSOLUTE MAXIMUM RATINGS
Table 2.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions 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.
Parameters
Ratings
Positive Supply Voltage (VDD) to GND
D+, ADD0, ADD1
D− to GND
−0.3 V to +6 V
−0.3 V to VDD + 0.3 V
−0.3 V to +0.6 V
−0.3 V to +6 V
50 mA
ALERT STBY
SCLK, SDATA,
Input Current
,
Input Current, D−
1 mA
ESD Rating, All Pins (Human Body Model) 2000 V
Continuous Power Dissipation
THERMAL CHARACTERISTICS
Up to 70°C
650 mW
16-lead QSOP package:
Derating Above 70°C
6.7 mW/°C
−55°C to +125°C
150°C
−65°C to +150°C
300°C
θ
θ
JA = 105°C/W
JC = 39°C/W
Operating Temperature Range
Maximum Junction Temperature (TJ MAX
Storage Temperature Range
Lead Temperature (Soldering 10 sec)
IR Reflow Peak Temperature
)
220°C
IR Reflow Peak Temperature for Pb-Free
260°C
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.
Rev. H | Page 4 of 20
ADM1023
PIN CONFIGURATION AND FUNCTION DESCRIPTION
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
NC
NC
V
STBY
SCLK
NC
DD
D+
ADM1023
TOP VIEW
(Not to Scale)
D–
NC
SDATA
ALERT
ADD0
NC
ADD1
GND
GND
NC = NO CONNECT
Figure 2. Pin Configuration
Table 3. Pin Function Descriptions
Pin No.
Mnemonic
Description
No Connect.
1, 5, 9, 13, 16
NC
2
VDD
Positive Supply, 3 V to 5.5 V.
3
4
6
7, 8
10
11
12
14
15
D+
D−
ADD1
GND
ADD0
ALERT
SDATA
SCLK
STBY
Positive Connection to Remote Temperature Sensor.
Negative Connection to Remote Temperature Sensor.
Three-State Logic Input, Higher Bit of Device Address.
Supply 0 V Connection.
Three-State Logic Input, Lower Bit of Device Address.
Open-Drain Logic Output Used as Interrupt or SMBus
Logic Input/Output, SMBus Serial Data. Open-drain output.
Logic Input, SMBus Serial Clock.
Logic Input Selecting Normal Operation (High) or Standby Mode (Low).
ALERT
.
tHD;STA
tR
tLOW
tF
SCL
SDA
tHD;DAT
tSU;STA
tSU;DAT
tHIGH
tSU;STO
tHD;STA
tBUF
S
P
P
S
Figure 3. Diagram for Serial Bus Timing
Rev. H | Page 5 of 20
ADM1023
TYPICAL PERFORMANCE CHARACTERISTICS
20
3
2
15
D+ TO GND
10
UPPER SPEC LEVEL
5
0
1
–5
0
–10
D+ TO V
DD
–1
–2
–3
–15
–20
–25
–30
LOWER SPEC LEVEL
1
10
LEAKAGE RESISTANCE (MΩ)
100
50
60
70
80
90
100
110
120
TEMPERATURE (°C)
Figure 4. Temperature Error vs. Resistance from Track to VDD and GND
Figure 7. Temperature Error of ADM1023 vs. Pentium III Temperature
5
14
12
10
8
4
250mV p-p REMOTE
3
2
6
4
100mV p-p REMOTE
1
2
0
0
100
–2
1k
10k
100k
1M
10M
100M
2
4
6
8
10
12
14
16
18
20
22
24
FREQUENCY (Hz)
CAPACITANCE (nF)
Figure 5. Remote Temperature Error vs. Supply Noise Frequency
Figure 8. Temperature Error vs. Capacitance Between D+ and D−
9
70
60
50
40
100mV p-p
8
7
6
5
4
V
= 3.3V
DD
30
20
10
0
3
50mV p-p
2
1
V
= 5V
DD
25mV p-p
1M 10M
0
1
10
100
1k
10k
100k
100M
1
5
10
25
50
75
100 250 500 750 1000
FREQUENCY (Hz)
SCLK FREQUENCY (kHz)
Figure 6. Temperature Error vs. Common-Mode Noise Frequency
Figure 9. Standby Supply Current vs. SCLK Frequency
Rev. H | Page 6 of 20
ADM1023
4
3
2
1
100
80
60
40
20
0
10mV p-p
0
100k
–20
1M
10M
FREQUENCY (Hz)
100M
1G
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
SUPPLY VOLTAGE (V)
Figure 10. Temperature Error vs. Differential-Mode Noise Frequency
Figure 12. Standby Supply Current vs. Supply Voltage
550
500
450
400
350
300
250
125
100
75
50
25
0
REMOTE
TEMPERATURE
INT
TEMPERATURE
200
3.3V
150
100
5V
50
0.0625 0.1250 0.2500 0.5000 1.0000 2.0000 4.0000 8.0000
CONVERSION RATE (Hz)
0
1
2
3
4
5
6
7
8
9
10
TIME (Seconds)
Figure 11. Operating Supply Current vs. Conversion Rate, VDD = 5 V and 3.3 V
Figure 13. Response to Thermal Shock
Rev. H | Page 7 of 20
ADM1023
THEORY OF OPERATION
FUNCTIONAL DESCRIPTION
limits are stored as 8-bit values and the remote temperature
limits as 11-bit values. Out-of-limit comparisons generate flags
that are stored in the status register, and one or more out-of-
The ADM1023 contains a two-channel analog-to-digital
converter (ADC) with special input-signal conditioning to
enable operation with remote and on-chip diode temperature
sensors. When the ADM1023 is operating normally, the ADC
operates in a free-running mode. The analog input multiplexer
alternately selects either the on-chip temperature sensor to
measure its local temperature or the remote temperature sensor.
These signals are digitized by the ADC, and the results are
stored in the local and remote temperature value registers. Only
the eight most significant bits (MSBs) of the local temperature
value are stored as an 8-bit binary word. The remote tempera-
ture value is stored as an 11-bit binary word in two registers.
The eight MSBs are stored in the remote temperature value
high byte register at Address 0x01. The three least significant
bits (LSBs) are stored, left justified, in the remote temperature
value low byte register at Address 0x10.
ALERT
limit results cause the
output to pull low.
Registers can be programmed, and the device controlled and
configured, via the serial system management bus (SMBus).
The contents of any register can also be read back via the
SMBus.
Control and configuration functions consist of
• Switching the device between normal operation
and standby mode.
ALERT
• Masking or enabling the
• Selecting the conversion rate.
output.
On initial power-up, the remote and local temperature values
default to −128°C. The device normally powers up converting,
making a measure of local and remote temperature. These
values are then stored before making a comparison with the
stored limits. However, if the part is powered up in standby
Error sources such as PCB track resistance and clock noise
can introduce offset errors into measurements on the remote
channel. To achieve the specified accuracy on this channel,
these offsets must be removed, and two offset registers are
provided for this purpose at Address 0x11 and Address 0x12.
STBY
mode (
pin pulled low), no new values are written to the
register before a comparison is made. As a result, both RLOW
and LLOW are tripped in the status register, thus generating an
An offset value may automatically be added to or subtracted
from the measurement by writing an 11-bit, twos complement
value to Register 0x11 (high byte) and Register 0x12 (low byte,
left-justified).
ALERT
output. This may be cleared in one of two ways:
•
Change both the local and remote lower limits to –128°C
and read the status register (which in turn clears the
The offset registers default to 0 at power-up and have
no effect if nothing is written to them.
ALERT
output).
•
Take the part out of standby and read the status register
ALERT
when the measured values are within the limit values.
The measurement results are compared with local and remote,
high and low temperature limits, stored in six on-chip limit
registers. As with the measured value, the local temperature
(which in turn clears the
output). This works only
V
DD
I
N × I
I
BIAS
D+
1
V
OUT+
C1
TO ADC
REMOTE
SENSING
TRANSISTOR
BIAS
DIODE
V
D–
OUT–
LOW-PASS FILTER
fC = 65kHz
1
CAPACITOR C1 IS OPTIONAL. IT IS ONLY NECESSARY IN NOISY ENVIRONMENTS.
C1 = 1000pF MAX.
Figure 14. Input Signal Conditioning
Rev. H | Page 8 of 20
ADM1023
MEASUREMENT METHOD
SOURCES OF ERRORS ON THERMAL TRANSISTORS
MEASUREMENT METHOD
A simple method of measuring temperature is to exploit the
negative temperature coefficient of a diode, or the base emitter
voltage of a transistor, operating at constant current. Thus, the
temperature may be obtained from a direct measurement of VBE
where
The Effect Of Ideality Factor (n)
The effects of ideality factor (n) and beta (β) of the temperature
measured by a thermal transistor are described in this section.
For a thermal transistor implemented on a submicron process,
such as the substrate PNP used on a Pentium III processor, the
temperature errors due to the combined effect of the ideality
factor and beta are shown to be less than 3°C. Equation 2 is
optimized for a substrate PNP transistor (used as a thermal
diode) usually found on CPUs designed on submicron CMOS
processes such as the Pentium III processor. There is a thermal
diode on board each of these processors. The n in Equation 2
represents the ideality factor of this thermal diode. This ideality
factor is a measure of the deviation of the thermal diode from
ideal behavior.
(
IC
)
nKT
(1)
VBE
=
×1n
q
IS
This technique, however, requires calibration to nullify the
effect of the absolute value of VBE, which varies from device
to device.
The technique used in the ADM1023 is to measure the change
in VBE when the device is operated at two different collector
currents.
This is given by
According to Pentium III processor manufacturing specifications,
measured values of n at 100°C are
nKT
(2)
Δ VBE
=
×1n
(N)
q
nMIN = 1.0057 < nTYPICAL = 1.008 < nMAX = 1.0125
where:
K is Boltzmann’s constant.
The ADM1023 takes this ideality factor into consideration
when calculating temperature TTD of the thermal diode. The
ADM1023 is optimized for nTYPICAL = 1.008; any deviation
on n from this typical value causes a temperature error that
is calculated below for the nMIN and nMAX of a Pentium III
processor at TTD = 100°C.
q is the charge on the electron (1.6 × 10–19 Coulombs).
T is the absolute temperature in Kelvins.
N is the ratio of the two collector currents.
1.0057 − 1.008
n is the ideality factor of the thermal diode (TD).
Δ TMIN
=
×
×
(
273.15 Kelvin + 100oC
)
)
= −0.85oC
1.008
To measure ΔVBE, the sensor is switched between operating
currents of I and NI. The resulting waveform is passed through
a low-pass filter to remove noise, then to a chopper-stabilized
amplifier that performs the functions of amplification and
rectification of the waveform to produce a dc voltage propor-
tional to ΔVBE. This voltage is measured by the ADC, which
gives a temperature output in binary format. To further reduce
the effects of noise, digital filtering is performed by averaging
the results of 16 measurement cycles. Signal conditioning and
measurement of the internal temperature sensor are performed
in a similar manner.
1.0125 − 1.008
Δ TMAX
=
(
273.15 Kelvin + 100oC
= +1.67oC
1.008
Thus, the temperature error due to variation on n of the
thermal diode for a Pentium III processor is about 2.5°C.
In general, this additional temperature error of the thermal
diode measurement due to deviations on n from its typical
value is given by
n −1.008
Δ T =
×
(
273.15 Kelvin + TTD
)
Figure 14 shows the input signal conditioning used to measure
the output of an external temperature sensor. This figure shows
the external sensor as a substrate PNP transistor, provided for
temperature monitoring on some microprocessors, but it could
equally well be a discrete transistor. If a discrete transistor is
used, the collector is not grounded and should be connected
to the base. To prevent ground noise from interfering with the
measurement, the more negative terminal of the sensor is not
referenced to ground but is biased above ground by an internal
diode at the D− input. If the sensor is operating in a noisy
environment, C1 may optionally be added as a noise filter.
Its value is 1000 pF maximum. See the Layout Considerations
section for more information on C1.
1.008
where TTD is in °C.
Beta of Thermal Transistor (β)
In Figure 14, the thermal diode is a substrate PNP transistor
where the emitter current is forced into the device. The deriva-
tion of Equation 2 assumed that the collector currents were
scaled by N as the emitter currents were also scaled by N.
Thus, this assumes that beta (β) of the transistor is constant
for various collector currents. Figure 15 shows typical β
variation vs. collector current for Pentium III processors at
100°C. The maximum β is 4.5 and varies less than 1% over
the collector current range from 7 μA to 300 μA.
Rev. H | Page 9 of 20
ADM1023
β
< 4.5
Table 5. Extended Temperature Resolution
(Remote Temperature Low Byte)
MAX
I
E
Δβ
Extended Resolution (°C)
Remote Temperature Low Byte
0.000
0.125
0.250
0.375
0.500
0.625
0.750
0.875
0000 0000
0010 0000
0100 0000
0110 0000
1000 0000
1010 0000
1100 0000
1110 0000
β
β
I
=
I
E
C
β+1
I
(mA)
C
7
300
Figure 15. Variation of β with Collector Currents
Expressing the collector current in terms of the emitter current
IC = IE [β/(β + 1)]
where:
REGISTER FUNCTIONS
The ADM1023 contains registers that are used to store the
results of remote and local temperature measurements and high
and low temperature limits, and to configure and control the
device. A description of these registers follows, and further
details are given in Table 6 to Table 10. Most of the registers
for the ADM1023 are dual-port and have different addresses
for read and write operations. Attempting to write to a read
address or to read from a write address produces an invalid
result. Register addresses above 0x14 are reserved for future
use or factory test purposes and should not be written to.
β(300 μA) = β(7 μA)(1 + ε ).
ε = Δβ/β and β = β(7 μA).
Rewriting the equation for ΔVBE, to include the ideality factor,
n, and beta, β yields
⎡
⎢
⎣
⎤
⎥
⎦
(
1 + ε
)
×
)
(
β + 1
)
nKT
q
(3)
Δ VBE
=
× ln
× N
(
1 + ε β + 1
All β variations of less than 1% (ε < 0.01) contribute to
temperature errors of less than 0.4°C.
Address Pointer Register
The address pointer register does not have, nor does it require,
an address, because it is the register to which the first data byte
of every write operation is automatically written. This data byte
is an address pointer that sets up one of the other registers for
the second byte of the write operation or for a subsequent read
operation.
TEMPERATURE DATA FORMAT
One LSB of the ADC corresponds to 0.125°C, so the ADM1023
can measure from 0°C to 127.875°C. The temperature data
format and extended temperature resolution are shown in
Table 4 and Table 5.
Value Registers
Table 4. Temperature Data Format
(Local Temperature and Remote Temperature High Byte)
Temperature (°C)1
The ADM1023 has three registers to store the results of local
and remote temperature measurements. These registers are
written to by the ADC and can only be read over the SMBus.
Digital Output
0 000 0000
0 000 0001
0 000 1010
0 001 1001
0 011 0010
0 100 1011
0 110 0100
0 111 1101
0 111 1111
0
1
The Offset Register
Two offset registers are provided at Address 0x11 and
Address 0x12. These are provided so that the user may remove
errors from the measured values of remote temperature. These
errors may be introduced by clock noise and PCB track resis-
tance. See Table 7 for an example of offset values.
10
25
50
75
100
125
127
The offset value is stored as an 11-bit, twos complement value
in Register 0x11 (high byte) and Register 0x12 (low byte, left
justified). The value of the offset is negative if the MSB of
Register 0x11 is 1, and it is positive if the MSB of Register 0x11
is 0. This value is added to the remote temperature. These
registers default to 0 at power-up and have no effect if nothing
is written to them. The offset register can accept values from
−128.875°C to +127.875°C. The ADM1023 detects overflow so
the remote temperature value register does not wrap around
+127°C or −128°C.
1 The ADM1023 differs from the ADM1021 in that the temperature resolution
of the remote channel is improved from 1°C to 0.125°C, but it cannot
measure temperatures below 0°C. If negative temperature measurement is
required, the ADM1021 should be used.
The results of the local and remote temperature measurements
are stored in the local and remote temperature value registers
and are compared with limits programmed into the local and
remote high and low limit registers.
Rev. H | Page 10 of 20
ADM1023
Table 6. List of ADM1023 Registers
Read Address (Hex)
Write Address (Hex)
Name
Power-On Default
Not applicable
Not applicable
Address pointer
Undefined
00
01
02
Not applicable
Not applicable
Not applicable
Local temperature value
Remote temperature value high byte
Status
1000 0000 (0x80) (−128°C)
1000 0000 (0x80) (−128°C)
Undefined
03
09
Configuration
0000 0000 (0x00)
04
0A
Conversion rate
0000 0010 (0x02)
05
06
07
08
0B
0C
0D
0E
0F1
Local temperature high limit
Local temperature low limit
Remote temperature high limit high byte
Remote temperature low limit high byte
One-shot
0111 1111 (0x7F) (+127°C)
1100 1001 (0xC9) (−55°C)
0111 1111 (0x7F) (+127°C)
1100 1001 (0xC9) (−55°C)
Not applicable
10
11
12
13
14
19
20
FE
FF
Not applicable
11
12
13
Remote temperature value low byte
Remote temperature offset high byte
Remote temperature offset low byte
Remote temperature high limit low byte
Remote temperature low limit low byte
Reserved
Reserved
Manufacturer device ID
Die revision code
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000
Undefined
0100 0001 (0x41)
0011 xxxx (0x3x)
14
Not applicable
21
Not applicable
Not applicable
1 Writing to Address 0F causes the ADM1023 to perform a single measurement. It is not a data register as such; thus, it does not matter what data is written to it.
Table 7. Offset Values
Reading the status register clears the five flag bits, provided the
Remote
Temperature
(With
Remote
Temperature
(Without
Offset)
18°C
error conditions that caused the flags to be set have gone away.
While a limit comparator is tripped due to a value register
containing an
out-of-limit measurement or the sensor is open-circuit, the
corresponding flag bit cannot be reset. A flag bit can be reset
only if the corresponding value register contains an in-limit
measurement, or the sensor is good.
Offset Registers
Offset
Value
−4°C
0x11
0x12
Offset)
14°C
1111 1100
1111 1111
1111 1111
0000 0000
0000 0000
0000 0001
0000 0100
0000 0000
0000 0000
1110 0000
0000 0000
0010 0000
0000 0000
0000 0000
−1°C
17°C
18°C
−0.125°C
0°C
17.875°C
18°C
18°C
18°C
+0.125°C
+1°C
18.125°C
19°C
18°C
ALERT
register, but it resets when the
The
interrupt latch is not reset by reading the status
output has been serviced
18°C
ALERT
+4°C
22°C
18°C
by the master reading the device address, provided the error
condition has gone away and the status register flag bits have
been reset.
Status Register
Bit 7 of the status register (see Table 8) indicates that the ADC
is busy converting when it is high. Bit 6 to Bit 3 are flags indi-
cating the results of the limit comparisons.
Table 8. Status Register Bit Assignments
Bit
Name
Function
7
6
5
4
3
2
BUSY
At 1 when ADC converting
If the local and/or remote temperature measurement is above
the corresponding high temperature limit or below the corre-
sponding low temperature limit, one or more of these flags will
be set. Bit 2 is a flag that is set if the remote temperature sensor
is open-circuit. These five flags are NOR’d together, so that if
LHIGH1
LLOW1
RHIGH1
RLOW1
OPEN1
At 1 when local high temp limit tripped
At 1 when local low temp limit tripped
At 1 when remote high temp limit tripped
At 1 when remote low temp limit tripped
At 1 when remote sensor open-circuit
Reserved
any of them are high, the
interrupt latch is set, and the
ALERT
1 to 0
output goes low.
ALERT
1 These flags stay high until the status register is read or they are reset by POR.
Rev. H | Page 11 of 20
ADM1023
Configuration Register
Limit Registers
Two bits of the configuration register are used. If Bit 6 is 0,
which is the power-on default, the device is in operating mode
with the ADC converting (see Table 9). If Bit 6 is set to 1, the
device is in standby mode and the ADC does not convert.
The ADM1023 has six limit registers to store local and remote,
high and low temperature limits. These registers can be written
to and read back over the SMBus. The high limit registers
perform a > comparison, while the low limit registers perform
a < comparison. For example, if the high limit register is pro-
grammed as a limit of 80°C, measuring 81°C results in an alarm
condition. Even though the temperature range is 0 to 127°C,
it is possible to program the limit register with negative values.
This is for backward-compatibility with the ADM1021.
STBY
Standby mode can also be selected by taking the
pin low.
In standby mode, the values of remote and local temperature
remain at the value they were before the part was placed in
standby mode.
Bit 7 of the configuration register is used to mask the
output. If Bit 7 is 0, which is the power-on default, the
ALERT
ALERT
One-Shot Register
The one-shot register is used to initiate a single conversion and
comparison cycle when the ADM1023 is in standby mode, after
which the device returns to standby. This is not a data register
as such, and it is the write operation that causes the one-shot
conversion. The data written to this address is irrelevant and
is not stored.
output is enabled. If Bit 7 is set to 1, the
disabled.
output is
ALERT
Table 9. Configuration Register Bit Assignments
Bit
Name
Function
Power-On Default
7
MASK1
0 = ALERT Enabled
1 = ALERT Masked
0
SERIAL BUS INTERFACE
6
RUN/STOP 0 = Run
1 = Standby
Reserved
0
0
Control of the ADM1023 is carried out via the serial bus. The
ADM1023 is connected to this bus as a slave device, under the
control of a master device. Note that the SMBus SDA and SCLK
pins are three-stated when the ADM1023 is powered down, and
they do not pull down the SMBus.
5 to 0
Conversion Rate Register
The lowest three bits of this register are used to program the
conversion rate by dividing the ADC clock by 1, 2, 4, 8, 16, 32,
64, or 128, to give conversion times from 125 ms (Code 0x07)
to 16 seconds (Code 0x00). This register can be written to and
read back over the SMBus. The higher five bits of this register
are unused and must be set to 0. Use of slower conversion times
greatly reduces the device’s power consumption, as shown in
Table 10.
ADDRESS PINS
In general, every SMBus device has a 7-bit device address
(except for some devices that have extended, 10-bit addresses).
When the master device sends a device address over the bus,
the slave device with that address responds. The ADM1023
has two address pins, ADD0 and ADD1, to allow selection of
the device address, so that several ADM1023s can be used on
the same bus and to avoid conflict with other devices. Although
only two address pins are provided, these pins are three-state
and can be grounded, left unconnected, or tied to VDD, so that a
total of nine different addresses are possible, as shown in Table 11.
Table 10. Conversion Rate Register Code
Average Supply Current
μA Typ at VCC = 3.3 V
Data
Conversion/Sec
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0.0625
0.125
0.25
0.5
1
2
4
8
150
150
150
150
150
150
160
180
Note that the state of the address pins is sampled only at power-
up, so changing them after power-up has no effect.
Table 11. Device Addresses1
ADD0
ADD1
Device Address
0011 000
0011 001
0011 010
0101 001
0101 010
0101 011
1001 100
1001 101
1001 110
0
0
0
NC
NC
NC
1
1
1
0
NC
1
0
NC
1
0
NC
1
0x08 to 0xFF
Reserved
1 ADD0 and ADD1 are sampled at power-up only.
Rev. H | Page 12 of 20
ADM1023
The serial bus protocol operates as follows:
the slave device. Transitions on the data line must occur
during the low period of the clock signal and remain stable
during the high period, because a low-to-high transition
when the clock is high may be interpreted as a stop signal.
The number of data bytes that can be transmitted over the
serial bus in a single read or write operation is limited only
by what the master and slave devices can handle.
1. The master initiates data transfer by establishing a start
condition, defined as a high-to-low transition on the serial
data line, SDATA, while the serial clock line, SCLK, remains
high. This indicates that an address/data stream will follow.
All slave peripherals connected to the serial bus respond to
the start condition and shift in the next 8 bits. These bits
W
3. When all data bytes have been read or written, stop condi-
tions are established. In write mode, the master pulls the
data line high during the 10th clock pulse to assert a stop
condition. In read mode, the master device overrides the
Acknowledge bit by pulling the data line high during the
low period before the ninth clock pulse. This is known as
No Acknowledge. The master then takes the data line low
during the low period before the 10th clock pulse, then high
during the 10th clock pulse to assert a stop condition.
consist of a 7-bit address (MSB first) plus an R/ bit, which
determines the direction of the data transfer, that is, whether
data is written to, or read from, the slave device.
The peripheral whose address corresponds to the transmitted
address responds by pulling the data line low during the low
period before the ninth clock pulse, known as the Acknowl-
edge bit. All other devices on the bus remain idle while the
selected device waits for data to be read from or written to it.
W
If the R/ bit is 0, the master writes to the slave device. If the
W
R/ bit is 1, the master reads from the slave device.
2. Data is sent over the serial bus in sequences of nine clock
pulses, 8 bits of data followed by an Acknowledge bit from
1
9
1
9
SCLK
D6
D2
0
1
0
1
1
A1
A0
D7
D5
D4
D3
D1
SDATA
START BY
D0
R/W
ACK. BY
ACK. BY
ADM1023
MASTER
ADM1023
FRAME 1
SERIAL BUS ADDRESS BYTE
FRAME 2
ADDRESS POINTER REGISTER BYTE
1
9
SCLK (CONTINUED)
SDATA (CONTINUED)
D2
D1
D7
D6
D5
D4
D3
D0
ACK. BY
STOP BY
ADM1023 MASTER
FRAME 3
DATA BYTE
Figure 16. Writing a Register Address to the Address Pointer Register, then Writing Data to the Selected Register
1
0
9
1
9
SCLK
D6
D2
SDATA
1
0
1
1
A1
A0
R/W
D7
D5
D4
D3
D1
D0
START BY
MASTER
ACK. BY
ADM1023
ACK. BY
ADM1023
STOP BY
MASTER
FRAME 1
SERIAL BUS ADDRESS BYTE
FRAME 2
ADDRESS POINTER REGISTER BYTE
Figure 17. Writing to the Address Pointer Register Only
1
9
1
9
SCLK
R/W
A5
A1
A0
D2
A6
A4
A3
A2
D7
D5
D4
D3
D1
SDATA
D6
D0
NO ACK.
ACK. BY
ADM1023
STOP BY
START BY
MASTER
BY MASTER MASTER
FRAME 1
SERIAL BUS ADDRESS BYTE
FRAME 2
DATA BYTE FROM ADM1023
Figure 18. Reading Data from a Previously Selected Register
Rev. H | Page 13 of 20
ADM1023
•
Do not forget that ADM1023 registers have different
addresses for read and write operations. The write address
of a register must be written to the address pointer if data
is to be written to that register, but it is not possible to read
data from that address. The read address of a register must
be written to the address pointer before data can be read
from that register.
Any number of bytes of data may be transferred over the serial
bus in one operation, but it is not possible to mix read and write
in one operation because the type of operation is determined
at the beginning and cannot subsequently be changed without
starting a new operation.
For the ADM1023, write operations contain either one or two
bytes, while read operations contain one byte and perform the
following functions:
ALERT OUTPUT
ALERT
The
output goes low whenever an out-of-limit measure-
To write data to one of the device data registers or read data
from it, the address pointer register must be set so that the
correct data register is addressed. Data can then be written into
that register or read from it. The first byte of a write operation
always contains a valid address that is stored in the address
pointer register. If data is to be written to the device, the write
operation contains a second data byte that is written to the
register selected by the address pointer register.
ment is detected or if the remote temperature sensor is open-
circuit. It is an open drain and requires a 10 kΩ pull-up to VDD
.
Several
outputs can be wire-AND’ed together, so that
ALERT
the common line goes low if one or more of the
goes low.
outputs
ALERT
ALERT
The
output can be used as an interrupt signal to a
. Slave devices
processor, or it may be used as an
SMBALERT
This is illustrated in Figure 16. The device address is sent over
on the SMBus normally cannot signal to the master that they
SMBALERT
the bus followed by R/ set to 0. This is followed by two data
W
want to talk, but the
function allows them to do so.
bytes. The first data byte is the address of the internal data
register to be written to, which is stored in the address pointer
register. The second data byte is the data to be written to the
internal data register.
ALERT
One or more
SMBALERT
SMBALERT
outputs are connected to a common
line connected to the master. When the
line is pulled low by one of the devices, the
procedure shown in Figure 19 occurs.
When reading data from a register, there are two possibilities:
MASTER
RECEIVES
SMBALERT
1. If the ADM1023’s address pointer register value is unknown
or not the desired value, it is necessary to set it to the correct
value before data can be read from the desired data register.
This is done by performing a write to the ADM1023 as
before, but only the data byte containing the register read
address is sent, as data is not to be written to the register.
This is shown in Figure 17.
ALERT RESPONSE
DEVICE
ADDRESS
NO
ACK
START
RD ACK
STOP
ADDRESS
MASTER SENDS
ARA AND READ
COMMAND
DEVICE SENDS
ITS ADDRESS
SMBALERT
Figure 19. Use of
SMBALERT
Process
SMBALERT
1.
pulled low.
A read operation is then performed consisting of the serial
bus address, R/ bit set to 1, followed by the data byte read
from the data register. This is shown in Figure 18.
2. Master initiates a read operation and sends the alert response
address (ARA = 0001 100). This is a general call address that
must not be used as a specific device address.
W
2. If the address pointer register is known to be at the desired
address already, data can be read from the corresponding
data register without first writing to the address pointer
register.
ALERT
3. The device whose
output is low responds
to the ARA and the master reads its device address.
The address of the device is now known, and it can
be interrogated in the usual way.
ALERT
4. If more than one device’s
output is low, the one
NOTES
with the lowest device address has priority, in accordance
with normal SMBus arbitration.
•
It is possible to read a data byte from a data register with-
out first writing to the address pointer register. However,
it is not possible to write data to a register without writing
to the address pointer register even if the address pointer
register is already at the correct value. This is because the
first data byte of a write is always written to the address
pointer register.
5. Once the ADM1023 has responded to the ARA, it resets its
output, provided that the error condition that caused
ALERT
ALERT
SMBALERT
line remains
the
low, the master sends ARA again, and so on until all devices
whose outputs were low have responded.
no longer exists. If the
ALERT
Rev. H | Page 14 of 20
ADM1023
LOW POWER STANDBY MODES
SENSOR FAULT DETECTION
The ADM1023 can be put into a low power standby mode using
The ADM1023 has a fault detector at the D+ input that detects
if the external sensor diode is open-circuit. This is a simple
voltage comparator that trips if the voltage at D+ exceeds
STBY
hardware or software, that is, by taking the
input low or
is
by setting Bit 6 of the configuration register. When
STBY
high or Bit 6 is low, the ADM1023 operates normally. When
is pulled low or Bit 6 is high, the ADC is inhibited, and
VCC − 1 V (typical). The output of this comparator is checked
when a conversion is initiated and sets Bit 2 of the status
register if a fault is detected.
STBY
any conversion in progress is terminated without writing the
result to the corresponding value register.
If the remote sensor voltage falls below the normal measuring
range, for example, due to the diode being short-circuited,
the ADC outputs –128°C (1000 0000 000). Because the normal
operating temperature range of the device extends only down
to 0°C, this output code is never seen in normal operation and
can be interpreted as a fault condition.
The SMBus is still enabled. Power consumption in the standby
mode is reduced to less than 10 μA if there is no SMBus activity,
or 100 μA if there are clock and data signals on the bus.
STBY
These two modes are similar but not identical. When
is
low, conversions are completely inhibited. When Bit 6 is set,
In this respect, the ADM1023 differs from, and improves upon,
competitive devices that output 0 if the external sensor goes
short-circuit. Unlike the ADM1023, these other devices can
misinterpret a genuine 0°C measurement as a fault condition.
STBY
but
is high, a one-shot conversion of both channels can
be initiated by writing any data value to the one-shot register
(Address 0x0F).
If the external diode channel is not being used and is shorted
ALERT
out, the resulting
may be cleared by writing 0x80
(−128°C) to the low limit register.
Rev. H | Page 15 of 20
ADM1023
APPLICATIONS
FACTORS AFFECTING ACCURACY
LAYOUT CONSIDERATIONS
Remote Sensing Diode
Digital boards can be electrically noisy environments, and the
ADM1023 is measuring very small voltages from the remote
sensor; therefore, care must be taken to minimize noise induced
at the sensor inputs. The following precautions are needed:
The ADM1023 is designed to work with substrate transistors
built into processors or with discrete transistors. Substrate
transistors are generally PNP types with the collector connected
to the substrate. Discrete types can be either PNP or NPN,
connected as a diode (base-shorted to collector). If an NPN
transistor is used, the collector and base are connected to D+
and the emitter to D−. If a PNP transistor is used, the collector
and base are connected to D− and the emitter to D+.
•
Place the ADM1023 as close as possible to the remote
sensing diode. Provided that the worst noise sources, such as
clock generators, data/address buses, and CRTs, are avoided,
this distance can be 4 to 8 inches.
•
•
Route the D+ and D− tracks close together, in parallel, with
grounded guard tracks on each side. Provide a ground plane
under the tracks if possible (see Figure 20).
The user has no choice with substrate transistors, but if a
discrete transistor is used, the best accuracy is achieved
by choosing devices according to the following criteria:
Use wide tracks to minimize inductance and reduce noise
pickup. 10 mil track minimum width and spacing is
recommended.
•
Base emitter voltage greater than 0.25 V at 6 μA, at the
highest operating temperature.
•
Base emitter voltage less than 0.95 V at 100 μA, at the
lowest operating temperature.
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
GND
D+
•
•
Base resistance less than 100 Ω.
Small variation in hfe (approximately 50 to 150),
which indicates tight control of VBE characteristics.
D–
GND
Transistors such as 2N3904, 2N3906, or equivalents in SOT-23
packages are suitable devices to use.
Figure 20. Arrangement of Signal Tracks
Thermal Inertia and Self-Heating
•
Try to minimize the number of copper/solder joints, which
can cause thermocouple effects. Where copper/solder joints
are used, make sure that they are in both the D+ and D−
path and at the same temperature.
Accuracy depends on the temperature of the remote-sensing
diode and/or the internal temperature sensor being at the same
temperature as that being measured, and a number of factors
can affect this. Ideally, the sensor should be in good thermal
contact with the part of the system being measured, such as the
processor, for example. If it is not in good thermal contact, the
thermal inertia caused by the mass of the sensor causes a lag in
the response of the sensor to a temperature change. With the
remote sensor, this should not be a problem, as it will be either
a substrate transistor in the processor or a small package device,
such as SOT-23, placed in close proximity to it.
Thermocouple effects should not be a major problem as 1°C
corresponds to about 240 μV, and thermocouple voltages are
about 3 μV/°C of temperature difference. Unless there are
two thermocouples with a big temperature differential
between them, thermocouple voltages should be much less
than 240 μV.
•
•
•
Place a 0.1 μF bypass capacitor close to the VDD pin and
1000 pF input filter capacitors across D+, D− close to the
ADM1023.
The on-chip sensor, however, is often remote from the proces-
sor and monitors only the general ambient temperature around
the package. The thermal time constant of the QSOP-16
package is about 10 seconds.
If the distance to the remote sensor is more than 8 inches, the
use of twisted pair cable is recommended. This is effective
up to approximately 6 to 12 feet.
In practice, the package has electrical, and hence thermal,
connection to the printed circuit board. Therefore, the
temperature rise due to self-heating is negligible.
For longer distances (up to 100 feet), use shielded, twisted-
pair cable such as Belden #8451 microphone cable. Connect
the twisted pair to D+ and D−, and connect the shield to
GND close to the ADM1023. Leave the remote end of the
shield unconnected to avoid ground loops.
Rev. H | Page 16 of 20
ADM1023
Because the measurement technique uses switched current
sources, excessive cable and/or filter capacitance can affect
the measurement. When using long cables, the filter capacitor
may be reduced or removed.
The SCLK and SDATA pins of the ADM1023 can be interfaced
directly to the SMBus of an I/O chip. Figure 22 shows how the
ADM1023 might be integrated into a system using this type of
I/O controller.
Cable resistance can also introduce errors. A 1 Ω series
resistance introduces about 1°C error.
D–
ADM1023
PROCESSOR
D+
APPLICATION CIRCUITS
Figure 21 shows a typical application circuit for the ADM1023,
using a discrete sensor transistor connected via a shielded,
SYSTEM BUS
ALERT
twisted-pair cable. The pull-ups on SCLK, SDATA, and
DISPLAY
are required only if they are not already provided elsewhere in
the system.
SYSTEM
MEMORY
GMCH
DISPLAY
CACHE
PCI SLOTS
0.1μF
3V
HARD
V
DD
TO 5.5V
CD ROM
DISK
ADM1023
D+
SCLK
D–
PCI BUS
10kΩ 10kΩ 10kΩ
IN
ICH I/O
CONTROLLER
HUB
2 IDE PORTS
1000pF
SHIELD
TO
CONTROL
CHIP
SMBUS
SDATA
I/O
OUT
SUPER I/O
2N3904
ALERT
ADD0
USB USB
SET TO
REQUIRED
ADDRESS
FWH
(FIRMWARE
HUB)
2 USB PORTS
ADD1
GND
Figure 22. System Using ADM1023 and I/O Controller
Figure 21. Typical Application Circuit
Rev. H | Page 17 of 20
ADM1023
OUTLINE DIMENSIONS
0.193
BSC
16
1
9
8
0.154
BSC
0.236
BSC
PIN 1
0.069
0.053
0.065
0.049
8°
0°
0.010
0.004
0.025
BSC
0.012
0.008
0.050
0.016
SEATING
PLANE
0.010
0.006
COPLANARITY
0.004
COMPLIANT TO JEDEC STANDARDS MO-137-AB
Figure 23. 16-Lead Shrink Small Outline Package [QSOP]
(RQ-16)
Dimensions shown in inches
ORDERING GUIDE
Model
ADM1023ARQ
ADM1023ARQ-REEL
ADM1023ARQ-REEL7
ADM1023ARQZ1
ADM1023ARQZ-REEL1
ADM1023ARQZ-REEL71
EVAL-ADM1023EB
Temperature Range
Package Description
Package Option
RQ-16
RQ-16
RQ-16
RQ-16
0°C to 120°C
0°C to 120°C
0°C to 120°C
0°C to 120°C
0°C to 120°C
0°C to 120°C
16-Lead Shrink Small Outline Package [QSOP]
16-Lead Shrink Small Outline Package [QSOP]
16-Lead Shrink Small Outline Package [QSOP]
16-Lead Shrink Small Outline Package [QSOP]
16-Lead Shrink Small Outline Package [QSOP]
16-Lead Shrink Small Outline Package [QSOP]
Evaluation Board
RQ-16
RQ-16
1 Z = Pb-free part.
Rev. H | Page 18 of 20
ADM1023
NOTES
Rev. H | Page 19 of 20
ADM1023
NOTES
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2005 Analog Devices, Inc. All rights reserved. Trademarks and
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C00058–0–7/05(H)
Rev. H | Page 20 of 20
相关型号：
ADM1024ARU-REEL
IC 9-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO24, MO-153AD, TSSOP-24, Power Management Circuit
ADI
ADM1024ARU-REEL7
IC 9-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO24, MO-153AD, TSSOP-24, Power Management Circuit
ADI
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