ADM1025ARQZ

Overview

The ADM1025ARQZ is a hardware monitor ASIC manufactured by onsemi, housed in a 16-lead QSOP package. It operates within a supply voltage range of 3.0 V to 5.5 V with a typical active current of 2.5 mA and standby current of 500 µA. The device features five analog voltage inputs for monitoring 2.5 V, 3.3 V, 5 V, and 12 V supplies, plus an internal core voltage monitor. It includes an on-chip temperature sensor with ±3 °C accuracy and supports external diode sensing with ±5 °C accuracy. Communication occurs via an I²C compatible SMBus interface.

Feature Summary

• Provides up to eight measurement channels including five dedicated voltage inputs, one processor core voltage input, and two temperature sensing options.
• Features programmable digital inputs for reading processor VID bits, with integrated pull-up resistors on the standard ADM1025 variant.
• Includes a programmable open-drain output pin configurable as a reset generator or interrupt signal for limit violations.

Applications

• Network servers and personal computers
• Microprocessor-based office equipment
• Test equipment and measuring instruments

Procurement Notes

Verify component authenticity through authorized distribution channels. Confirm that the specific ordering suffix matches the required package type and lead finish specifications. Ensure compliance with relevant environmental directives applicable to the intended deployment region before finalizing procurement orders.

Selection Notes

Select this component when system design requires comprehensive monitoring of multiple power rails and thermal conditions via a serial bus interface. Consider the ADM1025A variant if open-drain VID inputs are preferred over the internal pull-ups found in the standard ADM1025 model. Evaluate the 16-lead QSOP package constraints against available PCB real estate.

Part Context

This component belongs to the ADM1025/ADM1025A family of low-cost PC hardware monitor ASICs. Originally developed by Analog Devices, the product line was transferred to onsemi. These devices are designed specifically for microprocessor-based systems requiring reliable status reporting and protection mechanisms.

Replacement Considerations

Direct replacements include the ADM1025AARQZ variant, which differs primarily in VID input configuration. Verify pinout compatibility and register mapping before substituting other hardware monitor ICs from different manufacturers.

FAQ

How is the SMBus address determined?

The seven-bit address consists of fixed upper bits (01011) and two lower bits determined by the logic state of the ADD pin at power-up.

What is the conversion time for external temperature measurements?

External temperature measurements take nominally 34.8 ms due to averaging over 16 conversions to reduce noise.

Can the device monitor its own supply voltage?

Yes, the VCC pin serves as both the power supply input and an analog input to monitor the processor core voltage.