[sdiy] Using non-linear passives

[Tom Wiltshire]

On 5 Apr 2017, at 19:11, Mattias Rickardsson <mr at analogue.org> wrote:

> On 5 April 2017 at 20:03, Tom Wiltshire <tom at electricdruid.net> wrote:
>> It looks to me there's something we're not understanding (or
>> misunderstanding) here. There's no way a capacitor that is spec'd to 35V
>> loses 90% of its capacitance by 35V. That simply wouldn't be *useful*.
> 
> Yes, they are still useful for many applications - if you know the
> voltage dependency and your DC voltage, and and choose your capacitors
> accordingly. :-)
> 
> /mr

Ok, in that case, I guess my question would be why call it 4.7uF/35V if it isn't?! :)

I notice all the parts talked about are in the uF range, and these are very small caps we're looking at. Would this problem decrease for smaller values where you're not trying to squeeze so much capacitance into such a small package? 220nF? 47nF? 100p?

Thanks for pointing it out though. I wouldn't have imagined such a spec was remotely realistic.

Tom