ON Semiconductor MAX809STRG Microprocessor Supervisor Circuit, 3-pin SOT-23

The ON Semiconductor MAX809STRG is a high-performance, 3-pin microprocessor supervisor circuit designed to monitor the VCC supply voltage in digital systems. It provides a reliable, active-low reset signal to a host processor to ensure proper system initialisation and operation, preventing data corruption during power-up, power-down, or brown-out conditions.

This integrated circuit requires no external components for its core function, simplifying board design and saving space. It features a factory-trimmed timeout delay of 460ms, ensuring the reset signal is held active for a sufficient period after VCC rises above the threshold voltage. The device is optimised to reject fast transient glitches on the VCC line, providing excellent immunity to power supply noise and enhancing overall system reliability.

A key benefit is its very low supply current, which makes it ideal for power-sensitive applications. The RESET output is guaranteed to be valid down to a VCC of just 1V, and its compatibility with hot-plug applications adds to its versatility in modular or serviceable systems.

Primary Features & Benefits

• Integrated Solution: No external components required for basic reset monitoring.
• High Reliability: Provides a guaranteed reset signal during power anomalies.
• Transient Immunity: Effectively filters out fast glitches on the supply line.
• Low Power: Very low supply current is ideal for portable and battery-powered devices.
• Wide Voltage Range: Operates from a supply voltage of 1V to 5.5V.
• Compact Package: Supplied in a space-saving SOT-23-3 surface-mount package.

Specifications

• Reset Threshold Voltage: 2.93V (nominal)
• Reset Output Type: Active-Low, Push-Pull
• Delay Time: 460ms (factory-trimmed)
• Supply Voltage Range: 1V to 5.5V
• Number of Pins: 3