MOSFETs, N to P channel

[almondcity]

Hi all,

I'm trying to replace some N-channel BS170 MOSFETs for P-channel BS250s and something's not going right. I'm wondering if this zener could be my issue, does it need to reverse directions? I've read that it's static protection.



I'm trying to build this circuit:

Fuzzhead Fx MOSFET Pie V2

Verified

dirtboxlayouts.blogspot.com

Any direction would be helpful. I'm using a charge pump to get -9V power but otherwise I haven't changed anything. I'm measuring around -5-6V on the drains of all MOSFETs except the first one, which is at -9V. Wondering if I have something going on there, I expected it to have a similar lower voltage.

Thanks

 

[jwin615]

Zener is for esd. If you inverted the rails you could reverse it, or just temporarily remove it and ground yourself well

 

[almondcity]

FYI removing the zener fixed my issue, which I guess means I had it reversed