The ADM1021 is a low cost microprocessor system temperature monitor with the following features: Replacement for MAX1617; On-Chip and Remote Temperature Sensing; No Calibration Necessary; 1°C Accuracy for On-Chip Sensor; 3°C Accuracy for Remote Sensor; Programmable Conversion Rate and Delay; Support Programmable Alerts; Support Programmable Interrupts; SMBus Bus Interface.
The ADM1021 provides a low‑cost solution for monitoring processor and system temperatures. It measures an on‑chip sensor and a remote diode‑connected transistor, delivering temperature data over a two‑wire SMBus compatible serial interface. Programmable high and low temperature limits generate an ALERT output that can be used as an interrupt or SMBus alert.
The device operates from 3.0 V to 5.5 V, consumes only a few tens of picoamps in standby, and is supplied in a 16‑lead QSOP package. Detailed register maps, pin functions, and timing diagrams are included to aid hardware and firmware integration.
| Supply Voltage Range | 3.0 V – 5.5 V |
|---|---|
| Standby Supply Current | 3 pA – 10 pA |
| Operating Temperature Range | -55 °C to +125 °C |
| Package | 16‑Lead QSOP |
| Conversion Rate (lowest code) | 0.0625 Hz |
It uses a two‑wire SMBus serial interface compatible with SMBus standards.
High and low temperature limits are programmed over the SMBus and stored in the device’s limit registers.
The standby supply current is between 3 pA and 10 pA at 3.3 V with no SMBus activity.
Pin 11 (ALERT) is an open‑drain logic output used as an interrupt or SMBus alert.