Two Transistors in a single circuit

Hello everyone,

For my project it is neccessary to change the current direction inside the circuit.
I figured that it would be best to do so using 4 Transistors to be able to switch each pole.

Therefor i need to control two Transistor with one pin, but i struggle on doing so.

Assuming a valid data sheet my transistor strukture is ECB.
I built a test circuit to try control two transistors at once.

The tansistors are functional, because the circuit works if I take one of them out.

Why does’nt this work? What function of the transistors did i get wrong?

Please see Picture below.

Thanks

Hi,
Welcome to the forum.

You need to google arduino H-Bridge.

Your circuit will not reverse the current.

Your LED will not work if you reverse the current through it, unless it is a special two or three colour LED.

Tom.... :slight_smile:

I know, this is just an example using the led.

However If i get this to work, I believe it will fix my real project.

F**ing has a perfectly good Schematic view. The breadboard view looks pretty but it's actually worse than useless.

H-bridge motor controllers are so widely available that I would always choose a pre-built motor controller for this, even if I'm only switching one or two LEDs. I note that you didn't tell us what you actually want to switch - how many amps and volts do you really need?

This site may help you: www.xyproblem.info

Hi,

Felix_N:
I know, this is just an example using the led.?

However If i get this to work, I believe it will fix my real project.

What is your REAL project, we may be able to help you with a simple solution.
If you don't give us the full picture, after many pages we may find the solution will not fit "THE REAL PROJECT"

Tom... :slight_smile: