In the publications that describe several variable DC power supply (regulated, variable or fixed voltage, for bench or hobby type stuff) are also described several overvoltage protection schemes. Some of them use an MC3423P to fire an SCR to blow a fuse. The nice thing about this IC is that it fires at about 2.5 volts so to use it a voltage divider is needed - in that voltage divider is a potentiometer that allows adjustment of the trip setting. The publications recommend the use to protect against pass transistor failure - so it doesnt' ruin whatever you have connected to the power supply. I might use it to set an upper limit if I were experimenting with a variable supply - just in case I screw up and go too far.
The MC34223P has been around a while. Any better ICs or similar adjustable schemes available??
Thanks.
The MC34223P has been around a while. Any better ICs or similar adjustable schemes available??
Thanks.