Using a (linear) regulator with enable pin as a load switch…

It is a common (hardware) design principle that the regulated/supply voltage remain on the PCB and that it is not provided on any connector external to the board.

I need to provide power to an external switch which when closed will be shorted to ground.
The switch will be normally closed.

I want the circuit to be bulletproof, but as simple as possible (if that isn't mutually exclusive).

I know of a couple of approaches but was interested to hear what people say...

1. I could use a series resistor connected to Vcc (i.e. a pull-up) to power the switch
2. I could make a current limited load switch out of discrete components
3. Has it been done before to use a linear regulator (with enable pin) as a protected load switch

I'm mostly interested in "3"...
Most regulators are quite robust - have low Iq, over temp, short circuit/over current protection, some even reverse polarity... and the output is regulated

Thanks, Bye

As long as the voltage at the EN input is within the operating limits of the device (think ESD strikes on the switch, etc) that will work fine.

There are plenty of dedicated load switch ICs that might meet you needs, what voltage and current ranges are you looking at switching? Also, do you know what the nature of the load will be (purely resistive, inductive, etc)?

Hi,Sam Manning

Refer my file attached your requirement is there.
review my rating good luck.

V.Sambath kumar

Hi Sam Manning,

Forgot to attach the file here it is.


V.Sambath kumar.