ADHD input buffer, Q5 wrong?

[mstrat]

Unless I'm misunderstanding, the schematic for ADHD v2 and the board are contradictory for Q5.

The schematic has the Drain going toward R27 to VCC, and the Source going to R29 and R26 toward ground.

The board, at least as pictured on https://www.pedalpcb.com/product/adhd/ has those two reversed.

Can anyone shed some light on this? e.g. is the silkscreen wrong on the board? Or is the schematic drawn incorrectly?

 

[Robert]

Nope, the schematic and silkscreen are both correct.

Look closely, Q5 is inverted on the schematic. (Although it's probably irrelevant, this matches the original)

 

[mstrat]

So the Source is in fact connected to R27? and the drain toward the ground?

Sorry I guess I'm not familiar with that inversion (the arrow moved to the top?)

Thanks again!

 

[Robert]

That's correct. The source and drain and interchangeable so it really should make no difference either way.

I assume it was done that way on the original to aide in trace routing. Rather than change it I just left it as-is.