ADM1021AARQZ-REEL ON Semiconductor, ADM1021AARQZ-REEL Datasheet
ADM1021AARQZ-REEL
Specifications of ADM1021AARQZ-REEL
Related parts for ADM1021AARQZ-REEL
ADM1021AARQZ-REEL Summary of contents
Page 1
ADM1021A Low Cost Microprocessor System Temperature Monitor Microcomputer The ADM1021A is a two−channel digital thermometer and under/overtemperature alarm, intended for use in personal computers and other systems requiring thermal monitoring and management. The device can measure the temperature of a ...
Page 2
ON−CHIP TEMPERATURE LOCAL TEMPERATURE SENSOR VALUE REGISTER D+ 3 A−TO−D ANALOG MUX D- CONVERTER 4 BUSY RUN/STANDBY REMOTE TEMPERATURE VALUE REGISTER EXTERNAL DIODE OPEN−CIRCUIT ADM1021A GND GND NC DD ABSOLUTE MAXIMUM ...
Page 3
PIN ASSIGNMENT Pin No. Mnemonic D− ADD1 7 GND 8 GND ADD0 11 ALERT 12 SDATA SCLK 15 STBY 16 NC ELECTRICAL CHARACTERISTICS ...
Page 4
ELECTRICAL CHARACTERISTICS Parameter SMBus Interface (See Figure 2) Logic Input High Voltage STBY, SCLK, SDATA Logic Input Low Voltage STBY, SCLK, SDATA SMBus Output Low Sink Current ALERT Output Low Sink Current Logic Input Current, I ...
Page 5
TYPICAL PERFORMANCE CHARACTERISTICS GND –5 – –15 –20 –25 – LEAKAGE RESISTANCE (M ) Figure 3. Temperature Error vs. PC Board Track Resistance 9 100mV p−p ...
Page 6
TYPICAL PERFORMANCE CHARACTERISTICS 4 3 10mV p− 100k 1M 10M 100M FREQUENCY (Hz) Figure 9. Temperature Error vs. Differential−Mode Noise Frequency 100 –20 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 SUPPLY ...
Page 7
Functional Description The ADM1021A 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 ADM1021A is operating normally, the A−to−D converter operates in free−running mode. The analog input multiplexer ...
Page 8
To measure DV , the sensor is switched between BE operating currents of I and N × I. The resulting waveform is passed through a 65 kHz low−pass filter to remove noise, and then to a chopper−stabilized amplifier that performs ...
Page 9
Bit flag that is set if the remote temperature sensor is open−circuit. These five flags are NOR’d together so that if any of them ...
Page 10
Table 4. Configuration Register Bit Assignments Bit Name Function 7 MASK1 0 = ALERT Enabled 1 = ALERT Masked 6 RUN/STOP 0 = Run 1 = Standby Reserved Conversion Rate Register The lowest three bits of this ...
Page 11
The serial bus protocol operates as follows: 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 ...
Page 12
SCLK A6 SDATA A5 A4 START BY MASTER SERIAL BUS ADDRESS BYTE Figure 15. Writing to the Address Pointer Register Only 1 SCLK SDATA START BY MASTER SERIAL BUS ADDRESS BYTE Figure 16. Reading Data from ...
Page 13
Once the ADM1021A has responded to the alert response address, it resets its ALERT output, provided that the error condition that caused the ALERT no longer exists. If the SMBALERT line remains low, the master sends the ARA again, ...
Page 14
... ADM1021AARQZ 0°C to +100°C ADM1021AARQZ−R 0°C to +100°C ADM1021AARQZ−R7 0°C to +100°C †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. *The “Z’’ suffix indicates Pb−Free part. ...
Page 15
... Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada Fax: 303− ...