I have a circuit dilemma that I was hoping someone might be able to help with. I'm trying to drive a load with MOSFET, but the load is located far away from the circuit, and needs to be driven with a cable (in this case it's a solenoid and a lamp, but maybe something else tomorrow). The most common way to drive things with a MOSFET that I've seen to to connect the load up to V+ and have the FET provide a path to ground, like this:
Now my dillema is that I'm connecting it over a cable, more like this:
If I do it like this, one of the cable pins are always going to be at +24V relative to ground, so that if there's a short near the load (or something grounded touches the pins while plugging it in, etc.), current will flow, even if the device is "switched off" - that is the logic line is low.
I'm wondering if there's an easy way to configure the circuit so that the cable pins are [0V, GND] when off, and [24V, GND] when on (rather than [24V, ?] when off and [24V, GND] when on)?
Any suggestions are greatly appreciated!!