ADM1020AR-REEL-ADM1020AR-REEL7 Fast Delivery |IC PHOENIX CO.,LIMITED

ADM1020AR-REEL ,8-Lead, Low-Cost, System Temperature MonitorSpecifications subject to change without notice.–2– REV. 0ADM1020ABSOLUTE MAXIMUM RATINGS* PIN FUNC ..
ADM1020AR-REEL7 ,8-Lead, Low-Cost, System Temperature MonitorSPECIFICATIONSA MIN MAX DDParameter Min Typ Max Units Test Conditions/CommentsPOWER SUPPLY AND ADCT ..
ADM1021 ,The ADM1021 has been replaced by the ADM1021ASPECIFICATIONSA MIN MAX DDParameter Min Typ Max Unit Test Conditions/CommentsPOWER SUPPLY AND ADCTe ..
ADM1021AARQ ,Low-Cost Microprocessor System Temperature MonitorSPECIFICATIONSA MIN MAX DDParameter Min Typ Max Unit Test Conditions/CommentsPOWER SUPPLY AND ADCTe ..
ADM1021AARQ-REEL ,Remote Temperature Sensor with Serial InterfaceAPPLICATIONSthe serial bus, and an ALERT output signals when the on-chipDesktop Computersor remote ..
ADM1021AARQ-REEL ,Remote Temperature Sensor with Serial InterfaceSPECIFICATIONSA MIN MAX DDParameter Min Typ Max Unit Test Conditions/CommentsPOWER SUPPLY AND ADCTe ..
AH0014CD ,Dual DPST-TTL/DTL Compatible MOS Analog SwitchesAH0014/AH0014CDPDT,AH0015/AH0015CQuadSPST,AH0019/AH0019CDualDPST-TTL/DTLCompatibleMOSAnalogSwitches ..
AH0014CD ,Dual DPST-TTL/DTL Compatible MOS Analog SwitchesAH0014/AH0014CDPDT,AH0015/AH0015CQuadSPST,AH0019/AH0019CDualDPST-TTL/DTLCompatibleMOSAnalogSwitches ..
AH0015CD ,Dual DPST-TTL/DTL Compatible MOS Analog SwitchesFeaturesries is available in hermetic dual-in-line package.YgLarge analog voltage switching 10VThes ..
AH0019CD ,Dual DPST-TTL/DTL Compatible MOS Analog SwitchesFeaturesries is available in hermetic dual-in-line package.YgLarge analog voltage switching 10VThes ..
AH0019CD ,Dual DPST-TTL/DTL Compatible MOS Analog Switchesapplications such as commutators in data ac-YOperation over wide range of power suppliesquisition s ..
AH0019CD ,Dual DPST-TTL/DTL Compatible MOS Analog SwitchesAH0014/AH0014CDPDT,AH0015/AH0015CQuadSPST,AH0019/AH0019CDualDPST-TTL/DTLCompatibleMOSAnalogSwitches ..

ADM1020AR-REEL-ADM1020AR-REEL7
8-Lead, Low-Cost, System Temperature Monitor
REV.0
8-Lead, Low-Cost, System
Temperature Monitor
FUNCTIONAL BLOCK DIAGRAM
PRODUCT DESCRIPTION
The ADM1020 is a two-channel digital thermometer and
under/over temperature alarm, intended for use in personal
computers and other systems requiring thermal monitoring and
management. The device can measure the temperature of a
microprocessor using a diode-connected NPN or PNP transis-
tor, which may be provided on-chip in the case of the Pentium®
II or similar processors, or can be a low-cost discrete device
such as the 2N3904. 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 chan-
nel measures the output of an on-chip temperature sensor, to
monitor the temperature of the device and its environment.
The ADM1020 communicates over a two-wire serial interface
compatible with System Management Bus (SMBus) standards.
Under and over temperature limits can be programmed into the
devices over the serial bus, and an ALERT output signals when
the on-chip or remote temperature is out of range. This output
can be used as an interrupt, or as an SMBus alert.
SMBus is a trademark of Intel Corporation.
Pentium is a registered trademark of Intel Corporation.
FEATURES
On-Chip and Remote Temperature Sensing
No Calibration Necessary
18C Accuracy for On-Chip Sensor
38C Accuracy for Remote Sensor
Programmable Over/Under Temperature Limits
Programmable Conversion Rate
2-Wire SMBus™ Serial Interface
Supports SMBus Alert
70 mA Max Operating Current
3 mA Standby Current
+3 V to +5.5 V Supply
8-Lead SOIC Package
APPLICATIONS
Desktop Computers
Notebook Computers
Smart Batteries
Industrial Controllers
Telecommunication Equipment
Instrumentation
ADM1020–SPECIFICATIONS(TA = TMIN to TMAX, VDD = 3.0 V to 3.6 V, unless otherwise noted)
NOTESOperation at VDD = +5 V guaranteed by design, not production tested.Guaranteed by design, not production tested.
Specifications subject to change without notice.
ABSOLUTE MAXIMUM RATINGS*
Positive Supply Voltage (VDD) to GND . . . . . . . .–0.3 V, +6 V
D+, ADD . . . . . . . . . . . . . . . . . . . . . . . .–0.3 V, VDD + 0.3 V
D– to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . .–0.3 V, +0.6 V
SCLK, SDATA, ALERT . . . . . . . . . . . . . . . . . . . . .–0.3 V, +6 V
Input Current, SDATA . . . . . . . . . . . . . . . . . . . . .–1, –50 mA
Input Current, D– . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–1 mA
ESD Rating, all Pins (Human Body Model) . . . . . . . .4000 V
Continuous Power Dissipation
Up to +70°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . .650 mW
Derating above +70°C . . . . . . . . . . . . . . . . . . . .6.7 mW/°C
Operating Temperature Range . . . . . . . . . .–55°C to +125°C
Maximum Junction Temperature (TJ max) . . . . . . . . .+150°C
Storage Temperature Range . . . . . . . . . . . .–65°C to +150°C
Lead Temperature, Soldering
Vapor Phase 60 sec . . . . . . . . . . . . . . . . . . . . . . . . .+215°C
Infrared 15 sec . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+200°C
*Stresses above those listed under Absolute Maximum Ratings may cause perma-
nent 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.
THERMAL CHARACTERISTICS
8-Lead SOIC Package: qJA = 150°C/Watt.
PIN FUNCTION DESCRIPTION
PIN CONFIGURATION
VDD
ADD
SCLK
SDATA
ALERT
GND
ORDERING GUIDE
*REEL contains 2500 pieces; REEL7 contains 1000 pieces.
ADM1020
LEAKAGE RESISTANCE – MV
TEMPERATURE ERROR – 30
–20
Figure 1.Temperature Error vs. PC Board Track Resistance
FREQUENCY – Hz50M500
TEMPERATURE ERROR – 50k500k5M
Figure 2.Temperature Error vs. Power Supply Noise
Frequency
FREQUENCY – Hz50M500
TEMPERATURE ERROR – 50k500k5M
Figure 3.Temperature Error vs. Common-Mode Noise
Frequency
MEASURED TEMPERATURE11010
READING304050
100708090100
Figure 4.Pentium II Temperature Measurement vs.
ADM1020 Reading
Figure 5.Temperature Error vs. Capacitance Between
D+ and D–

SCLK FREQUENCY – Hz1M1k
SUPPLY CURRENT – 10k25k50k75k100k250k500k750k
Figure 6.Standby Supply Current vs. Clock Frequency
–Typical Performance Characteristics
FREQUENCY – Hz50M500
TEMPERATURE ERROR – 50k500k5M
100k25M
Figure 7.Temperature Error vs. Differential-Mode Noise
Frequency
CONVERSION RATE – Hz
SUPPLY CURRENT –
120
Figure 8.Operating Supply Current vs. Conversion
Rate
Figure 9.Standby Supply Current vs. Supply Voltage
Figure 10.Response to Thermal Shock
FUNCTIONAL DESCRIPTION
The ADM1020 contains a two-channel A-to-D converter with
special input-signal conditioning to enable operation with
remote and on-chip diode temperature sensors. When the
ADM1020 is operating normally, the A-to-D converter 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 stored in the local and
remote temperature value registers as 8-bit, twos complement
words.
The measurement results are compared with local and remote,
high and low temperature limits, stored in four on-chip regis-
ters. Out of limit comparisons generate flags that are stored in
the Status Register, and one or more out-of-limit results will
cause the ALERT output to pull low.
The limit registers can be programmed, and the device con-
trolled and configured, via the serial System Management Bus
(SMBus). The contents of any register can also be read back via
Control and configuration functions consist of:switching the device between normal operation and standby
mode.masking or enabling the ALERT output.selecting the conversion rate.
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, operated at constant current. Unfortu-
nately, this technique requires calibration to null out the effect
of the absolute value of VBE, which varies from device to device.
The technique used in the ADM1020 is to measure the change
in VBE when the device is operated at two different currents.
This is given by:
DVBE = KT/q · ln (N)
where:
ADM1020
Figure 11 shows the input signal conditioning used to measure
the output of an external temperature sensor. This figure shows
the external sensor as a substrate transistor, provided for tem-
perature monitoring on some microprocessors, but it could
equally well be a discrete transistor. If a discrete transistor is
used, the collector will not be grounded, and should be linked to
the base. To prevent ground noise interfering with the measure-
ment, 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 typi-
cally 2200 pF but should be no more than 3000 pF. See the
section on Layout Considerations for more information on C1.
To measure DVBE, the sensor is switched between operating
currents of I and N · I. The resulting waveform is passed
through a 65 kHz low-pass filter to remove noise, hence to a
chopper-stabilized amplifier that performs the functions of am-
plification and rectification of the waveform to produce a dc
voltage proportional to DVBE. This voltage is measured by the
ADC to give a temperature output in 8-bit twos complement
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 tempera-
ture sensor is performed in a similar manner.
TEMPERATURE DATA FORMAT
One LSB of the ADC corresponds to 1°C, so the ADC can
theoretically measure from –128°C to +127°C, although the
practical lowest value is limited to –65°C due to device maxi-
mum ratings. The temperature data format is shown in Table I.
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.
REMOTE
SENSING
TRANSISTOR
VOUT+
TO ADC
VOUT–
*CAPACITOR C1 IS OPTIONAL.
IT IS ONLY NECESSARY IN NOISY ENVIRONMENTS.
C1 = 2.2nF TYPICAL, 3nF MAX.
Figure 11.Input Signal Conditioning
Table I.Temperature Data Format
ADM1020 REGISTERS
The ADM1020 contains nine registers that are used to store the
results of remote and local temperature measurements, high and
low temperature limits, and to configure and control the device.
A description of these registers follows, and further details are
given in Tables II to IV. It should be noted that the ADM1020’s
registers 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, will produce an invalid result. Regis-
ter addresses above 0F are reserved for future use or used for
factory test purposes and should not be written to.
Address Pointer Register
The Address Pointer Register itself does not have, or require, an
address, as 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.

Partno	Mfg	Dc	Qty	Available	Descript
ADM1020AR-REEL \|ADM1020ARREEL	ADI	N/a	11000	avai	8-Lead, Low-Cost, System Temperature Monitor
ADM1020AR-REEL7 \|ADM1020ARREEL7	AD	N/a	8000	avai	8-Lead, Low-Cost, System Temperature Monitor