Power Supply Supervisory/Over and Undervoltage Protection Circuit

The MC3425 is a power supply supervisory circuit containing all the necessary functions required to monitor over and undervoltage fault conditions. These integrated circuits contain dedicated over and undervoltage sensing channels with independently programmable time delays. The overvoltage channel has a high current Drive Output for use in conjunction with an external SCR Crowbar for shutdown. The undervoltage channel input comparator has hysteresis which is externally programmable, and an open−collector output for fault indication.

• Dedicated Over and Undervoltage Sensing

• Programmable Hysteresis of Undervoltage Comparator

• Internal 2.5 V Reference

• 300 mA Overvoltage Drive Output

• 30 mA Undervoltage Indicator Output

• Programmable Time Delays

• 4.5 V to 40 V Operation