[sdiy] Will clamping diode work when power is off?

[MTG]

This is a cool idea, but I'm curious about the OP's problem. What's the 
use-case here where part of the rig is powered? Is this just 
power-on-off timing situation or is powering part of the system a normal 
part of using it?


On 5/29/2021 5:10 AM, S Ridley via Synth-diy wrote:
> 
> Another option is to invert the gate in the software, use the pin's 
> internal input pull-up and use an npn transistor to switch it to 0v.  I 
> suppose current might flow through the BC junction if the power is off, 
> but you'd be using a much higher base resistor on the input so current 
> through that route can be minimised.
> 
> Steve
>