Derailer Overdrive: X7S MLCCs

[Bucksears]

I'm almost done with my Derailer build, with the exception of the 2.2uF MLCCs (caps C12, 13 & 14).
I've heard too many things about X7Rs having issues with capacitance drift when voltage is applied; I picked up some 100V X7S caps for these spots, but want to run it by the forum before soldering. These are the only ones I could find small enough for these locations.

Will they be usable? They are directly connected to the VREF line on the schematic.

Thanks

 

[Stickman393]

X7Rs are about as good as you'll get in that form factor and value.

Film caps exist in that range, but they're huge. C0G's top out around 220 or (maybe?) 470nF. Electros tend to be worse in x7rs in certain areas (ESR, leakage).

No problems there.

 

[spi]

X7Rs having issues with capacitance drift when voltage is applied

It's an overdrive pedal--don't overthink it.

 

[Bucksears]

It's an overdrive pedal--don't overthink it.

But....but.......that goes against everything I know! Everything I AM!!


Will do

 

[Stickman393]

Don't feel bad. I do the same thing.

"Well, this is gonna be a bypass cap for an op amp, so X7R is ideal for that use. But this one's for a high pass filter, so I need either polypropylene or C0G...."

 

[JTEX]

100v rated X7* will work well just about anywhere in a pedal powered by 9 or 18V. They'll likely stay within +/-10% through any temperature change or voltage that a pedal is likely to see. Just don't use them where a tighter tolerance is needed (5% or less).