Kliche mini wrong voltage

[flippy69]

Hello, I built a Kliche mini for someone and as soon as they got it, they plugged into 12 v despite my repeated instructions NOT TO. I build him a new one and have the damaged one here. My question is: before I open it up, what am I looking at in terms of damage? What should I look for and what’s the best fix? Although I have been working on pedals for years, I never actually had someone do something so idiotic so I have never had to do such a repair. Thanks in advance.

 

[zgrav]

if you're lucky, you may only need to replace a fried charge pump. a visual and smell inspection may detect any caps that were too juiced before the charge pump gave up.

 

[flippy69]

Caps look good but I only use 50v on these ( thankfully) and the z diode is toast. The IC socket looks like it went through a tough time for sure.

 

[Robert]

The charge pump can handle 12V but that is the absolute maximum, anything above 12 (and sometimes 12) will damage them.

The zener should have prevented anything above 12V from reaching the charge pump, that's it's whole purpose, but it will likely be damaged.

Powering on 12V would have subjected the TL072 ICs to around 36V which is also their absolute maximum voltage.

So basically the most likely candidates for failure would be the zener, charge pump, and opamps...

You can just remove the zener for test purposes as long as you don't power it above 9V.

 

[flippy69]

Thank you!!

 

[flippy69]

The charge pump can handle 12V but that is the absolute maximum, anything above 12 (and sometimes 12) will damage them.

The zener should have prevented anything above 12V from reaching the charge pump, that's it's whole purpose, but it will likely be damaged.

Powering on 12V would have subjected the TL072 ICs to around 36V which is also their absolute maximum voltage.

So basically the most likely candidates for failure would be the zener, charge pump, and opamps...

You can just remove the zener for test purposes as long as you don't power it above 9V.

Well the diode was so burned that it melted the IC socket next to it. I replaced but kept the new diode raised because I wasn’t even sure if it was going to work and I didn’t want to further damage. I realize it looks slightly sloppy.
I then decided to have a little fun and replaced the IC’s with OP275’s and the 1N34’s with these old 1N281’s.
It works!!!!
I think it sounds better now than it did before it blew up if that’s possible