App note: Automotive power circuit handles interruptions and 72volt spikes
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This entry was posted in app notes and tagged automotive electronics, circuit, MAX6495.This circuit maintains power to the load regardless of momentary shorts or opens in the supply voltage, and includes a low-current overvoltage-protection IC (MAX6495) that protects the load against transient voltages up to 72V.
Comments
Q1 & Q2 are opposite polarity, but have the same part number. Likewise for Q3 & Q4. Hmmm…
IRF7105 has one P-channel and one N-channel MOSFET in it, so actually Q1 is IC1-A, Q2 is IC1-B
Also Q3 and Q4 are mirror images.
Would this still require a Schottkey diode for reverse voltage protection?
I don’t think you necessarily need a Schottky for reverse-voltage protection – any diode should do. The Schottky has a low forward-voltage drop, but there are other LDO diodes out there.
If there is a chance that the input will have reverse polarity, then you should check the MAX6495 data sheet for voltage tolerance on the pin 1 input. Q1 and Q3 should handle negative voltages, but I can’t be sure without checking their data sheets, too.