I have an rather complex circuit with button micro-switch in the middle (actually, it's RF remote control with 3 buttons).
I would like to be able to simulate the micro-switch click on it with one of the pins from my micro-controller.
To do so, I decided to install transistor in parallel manner. The problem is, micro-switch is neither the last nor the first element in circuit. And as I recall transistor needs to be connected to ground (NPN) and not just "somewhere in the middle".
My non-modified circuit with switch in the middle, between two LEDs (they are there just to make a concept of some "black box" before and after the micro-switch):
When I add an NPN transistor and tries to simulate the switch with it, the current is different:
If remove the part of the circuit that is "behind" switch (to GND), it works as switch simulator just fine:
What should I do in such case, when the circuit is already built, and I want to simulate switch "click" without moving the switch from it's place?