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Hi, I have virtually no experience in schematic design. I want to be able to switch a load of approximately 2A (@5V) from the GPIO of a raspberry PI.

I provided an example schematic here: https://www.circuitlab.com/circuit/r5pm7s/switch-raspberry-pi/

Unfortunately I don't know how to continue without breaking stuff. How do I continue from here?

@tback,

Hello and welcome to CL.

Sorry but you need to provide more info.

:)

Do you want to switch (a) 5V to a grounded load or (b) have the load connected to 5V and switch the ground end?

Do you want the switch protected against short circuits to:

for (a): ground

or

for (b) 5V?

How much voltage drop can you tolerate across the switch?

How fast do you need to switch (on/off edge times, on duration, off duration, pulse repetition frequency, etc.)?

What high and low level logic output voltages does the RaPi provide to control the switch?

What logic level output currents can the RasPi outputs source and sink to control the switch?

Is the control output from the RasPi a push-pull or open drain type of output?

If open drain then what max high level voltage can safely be applied to the RasPi output from an external source?

What logic sense do you want: high = switch closed or high = switch open?

That should give people enough to go on for now.

In the meanwhile, please see the section on "A design process" in:

https://www.circuitlab.com/forums/support/topic/58b454g6/op-amp-output-different-than-real-world/#comment_2195

Also have a read of:

https://www.circuitlab.com/forums/basic-electronics/topic/6n4hgm38/pnp-transistor-as-a-switch/#comment_3258