FM803RS3X

Supervisors Overview

The FM803RS3X is a voltage supervisory circuit manufactured by onsemi, formerly Fairchild Semiconductor. It monitors a single input voltage within a range of 1.1 V to 5.5 V. The device features an active low open-drain reset output with an internal pull-up resistor. Key electrical parameters include a typical reset delay time of 560 ms and a quiescent current of 6 uA. It operates reliably across a temperature range of -40°C to +105°C and is housed in a compact SOT-23-3 surface-mount package.

Supervisors Feature Summary

• Generates a reset pulse automatically when the monitored supply voltage falls outside specified tolerance limits
• Provides a guaranteed minimum reset pulse width to ensure proper system initialization upon power-up
• Integrates an internal pull-up resistor on the active low open-drain output for simplified circuit design

Supervisors Applications

• Microprocessor and microcontroller system supervision
• Portable battery-powered electronic devices
• General-purpose power supply monitoring circuits

Supervisors Procurement Notes

Verify component authenticity through authorized distribution channels as this part may be discontinued or subject to lifecycle changes. Confirm that the SOT-23-3 package dimensions and pinout align with existing PCB footprints. Ensure the specific threshold voltage variants meet the design requirements for the target application voltage levels before finalizing procurement plans.

Supervisors Selection Notes

Select this component for applications requiring low standby current and minimal board space due to its small footprint. Consider the fixed threshold voltages available for standard system rails such as 3.3V or 5.0V. Evaluate the operating temperature range to ensure suitability for industrial or automotive environments if required by the system specifications.

Supervisors Part Context

The FM803 series belongs to a family of 3-pin microprocessor supervisor circuits originally developed by Fairchild Semiconductor. Following the acquisition of Fairchild by onsemi, these products are now managed under the onsemi portfolio. The series provides essential power management functions for digital logic systems, ensuring reliable operation during power transitions.

Supervisors Replacement Considerations

Consult official cross-reference tools for parametrically similar parts from onsemi or other manufacturers. Verify compatibility regarding threshold voltages, reset delays, and package types before substituting.