Adding 2 caps together to make 1 value?

[steviejr92]

Hey guys, Starting a new project here and i dont have correct value cap i need 33pf but i have 10 pf and 22pf was wondering if it was possible to combine 2 caps to get the correct value?

 

[Brett]

Sure, you can combine them in parallel and the total capacitance will be the cumulative total. Buying the proper capacitor value is more ideal but yes, you can do this in a pinch.

 

[steviejr92]

Sure, you can combine them in parallel and the total capacitance will be the cumulative total. Buying the proper capacitor value is more ideal but yes, you can do this in a pinch.

Thanks for the reply time to get to building!

 

[Brett]

Thanks for the reply time to get to building!

Don't just take my word for it, here's more information on combining capacitors (for reference): https://learn.sparkfun.com/tutorials/capacitors/capacitors-in-seriesparallel

 

[fig]

I have a free groovy little app called EEToolkit. It does and SHOWS a lot of the math, obviously this one is easy enough to calculate, but it quickly answers the question of “what happens if I?”

 

[steviejr92]

Don't just take my word for it, here's more information on combining capacitors (for reference): https://learn.sparkfun.com/tutorials/capacitors/capacitors-in-seriesparallel

This just made me even more confident knowing this isnt as rare as i thought

 

[steviejr92]

I have a free groovy little app called EEToolkit. It does and SHOWS a lot of the math, obviously this one is easy enough to calculate, but it quickly answers the question of “what happens if I?”

Downloading ASAP!

 

[jimilee]

I have a free groovy little app called EEToolkit. It does and SHOWS a lot of the math, obviously this one is easy enough to calculate, but it quickly answers the question of “what happens if I?”

I loved it so much I got the pro version. I’ve been using it since it came out. Super helpful.

 

[fig]

I loved it so much I got the pro version. I’ve been using it since it came out. Super helpful.

Yeah, I just realized I upgraded too!

 

[SillyOctpuss]

Is that available on android or just IOS? I can't find it on the Google play store.

 

[steviejr92]

Is that available on android or just IOS? I can't find it on the Google play store.

i have ios its on there id imagine android too?

 

[SillyOctpuss]

Boo that sucks iphone and ipad only.

 

[Passinwind]

Hey guys, Starting a new project here and i dont have correct value cap i need 33pf but i have 10 pf and 22pf was wondering if it was possible to combine 2 caps to get the correct value?

Yep, as you already know by now. I do parallel cap footprints in certain critical locations on my own designs. So if I need a 1.12uF coupling cap to get the right bass rolloff it's no problem. This is really useful for resonant filters too.

 

[steviejr92]

Yep, as you already know by now. I do parallel cap footprints in certain critical locations on my own designs. So if I need a 1.12uF coupling cap to get the right bass rolloff it's no problem. This is really useful for resonant filters too.

thank you for the info! knowing this going forward is going to make these builds much easier without having to spend more money

 

[Passinwind]

thank you for the info! knowing this going forward is going to make these builds much easier without having to spend more money

Not just being chained to stock ISO values can be quite liberating. Even some of the stock values like .82uF can be very hard to find and out of spec/counterfeit parts end up coming into play fairly often.

 

[steviejr92]

This golden info for me i love learning ways around things. Exactly as you said its very liberating knowing i dont have to constrained anymore by *inbetween* values. So this is probably obvious but i should ask anyways this will work with resistors as well just use the teepee method?

 

[Dan0h]

Downloading now! What a great idea.

I have a free groovy little app called EEToolkit. It does and SHOWS a lot of the math, obviously this one is easy enough to calculate, but it quickly answers the question of “what happens if I?

 

[Passinwind]

This golden info for me i love learning ways around things. Exactly as you said its very liberating knowing i dont have to constrained anymore by *inbetween* values. So this is probably obvious but i should ask anyways this will work with resistors as well just use the teepee method?

Yep, but don't forget that you can put passive components in series to get new values as well. Doing the math ourselves in never a bad idea IMO, but an app like @fig linked or LTspice modeling makes this stuff trivially easy these days.

 

[steviejr92]

Yep, but don't forget that you can put passive components in series to get new values as well. Doing the math ourselves in never a bad idea IMO, but an app like @fig linked or LTspice modeling makes this stuff trivially easy these days.

I need to start messing with LTspice i have it downloaded but havent really played with it yet.

 

[Passinwind]

I need to start messing with LTspice i have it downloaded but havent really played with it yet.

It's a fantastic tool that I use nearly every day. You can download things like whole Fender tube amp models to get started: https://groups.io/g/LTspice

Even just using LTspice to archive build specs is pretty great, it's saved my butt quite a few times when I couldn't remember exactly what preamp format we used in a one off NAMM bass in 2018 or whatever.