Can someone tell me if the following circuit is sane? It's a fairly standard lowside switch, but I've added an LED plus resistor. V_GS on an IRF530 is about 2v, so I assume that a small LED won't lead to excessive voltage drop.

my attempt at a circuit

If that's not okay, is there a way to wire the LED in 'parallel' with the gate?

For the record, I also have NTD5867NLs, so that's an option. I know it has a lower V_GS.


It probably won't work - for 2 reasons;

  1. The LED will have a voltage drop (1.5V - 2.5V depending on type - independent of "size").
  2. The current through the LED will be ~0.5mA - you may or may not even see the glow.

You COULD run the LED (plus current limiting resistor) in parallel with the gate, but it would seem more sensible to use with the load.

  • so if I put one on the load side, how should I run it 'parallel' with the load so the load doesn't run through the resistor/led combo? I don't think true parallel is the right way to do it, as it would vary based on the load itself.
    – tedder42
    May 21 '18 at 1:21
  • 1
    @tedder42 a LED (plus current limiting resistor) can be run in parallel with the load, independent of what the load is doing, and will have ~5V across the LED plus resistor - indeed this is the only reliable of running specialist LED with a high voltage drop (blue LED can require up to 3.7V).
    – Milliways
    May 21 '18 at 1:42

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