FAN7687AMX

Power Supply Controllers, Monitors Overview

The FAN7687AMX is a secondary side monitoring integrated circuit manufactured by Fairchild Semiconductor, designed for PC power supply output supervision. It operates within a voltage range of 4 V to 15 V with a supply current of 1 mA. The device provides comprehensive protection including overvoltage, undervoltage, and overcurrent detection for 3.3V, 5V, and 12V outputs. It features dual overcurrent protection specifically for the 12V rail. The component utilizes an open-drain fault protection output and an open-drain power good output with a 300 ms delay. It supports latch functions controlled by the PSON pin and includes debounce timing of 2.3 ms.

Power Supply Controllers, Monitors Feature Summary

• Provides complete supervisory circuitry for switched mode power supply secondary sides
• Includes overvoltage, undervoltage, and overcurrent protection for standard rails
• Features dual overcurrent protection capability for 12V outputs
• Offers open-drain fault and power good outputs with configurable delays

Power Supply Controllers, Monitors Applications

• PC power supply output monitoring
• Switched mode power supply secondary side supervision
• System protection for 3.3V, 5V, and 12V rails

Power Supply Controllers, Monitors Procurement Notes

Verify the specific suffix 'AMX' against official datasheets to confirm package type and temperature range, as variations exist within the FAN768x family. Confirm RoHS compliance status and check for end-of-life notifications given the manufacturer's history. Ensure the open-drain output configurations match system requirements for pull-up resistors.

Power Supply Controllers, Monitors Selection Notes

Select this component when dual overcurrent protection on the 12V rail is required alongside standard OVP and UVP for multiple voltages. Consider the 300 ms power good delay and 38 ms PSON on/off delay for timing-sensitive applications. Verify that the 14-DIP or compatible surface mount package fits the PCB layout constraints.

Power Supply Controllers, Monitors Part Context

The FAN7687AMX belongs to the FAN7685/FAN7686/FAN7687 series of output supervisory circuits. These devices are engineered to replace discrete logic solutions in PC power supplies, reducing external component count while providing robust fault protection. The series integrates precise threshold detection and debouncing to prevent false triggering during transient events.

Power Supply Controllers, Monitors Replacement Considerations

FAN7685AN and FAN7686AN are related parts in the same series but lack the dual overcurrent protection feature found in the FAN7687.