# Does the Film Cap icon on the PCB mean I have to use film caps?



## bengarland (Feb 6, 2020)

I'm super confused about some of the PCBs when it comes to film box caps vs MLCCs. The guides almost never specify the capacitor types, so I'm assuming if there's a box icon on the PCB it means I should use a box film cap unless the guide says MLCC (some, like Hydra, do). Thing is, for example on the Stockade, it has a box for 47p on the PCB -- but my Mouser searching skills must be terrible, because I can't find a box cap in 47p that's 2.5mm wide and 5mm lead spacing, which is the size of the icon on the PCB. All of the 47p film box caps appear to be 4.5 mm wide. While I can probably jam it in there sideways, I ideally want everything to fit perfectly.

Anyone care to enlighten me on what I'm doing wrong? Should I be using MLCC for the "p" cap values? Is there some unknown rule I should be following about when to use MLCC vs film caps, if the guide doesn't say, and the PCBs all seem to use the "box cap" icon?


----------



## bengarland (Feb 6, 2020)

(in case I wasn't clear, it seems common that all of the "p" values of film caps are 4.5 mm wide / thick, and when they're side by side on the PCB, they won't fit -- only 2.5mm thick film caps will fit, and that's usually only the "n" values)


----------



## chongmagic (Feb 6, 2020)

A rule of thumb that I follow is to use MLCC caps for pf values. I use film or box type for nf values, in case other wise noted. You can use ceramic caps for pf values as well, I prefer MLCC caps. In the case of the Stockade, a 47pf MLCC cap will have the same spacing as a box type cap, most types not all, and will fit in that space.


----------



## bengarland (Feb 6, 2020)

Thanks! That's good to know -- finding pf film caps that fit the PCB is really difficult if not impossible for some values. MLCC is a lot easier.


----------



## bengarland (Feb 6, 2020)

*Here's another one:*

The Backfeeder board shows a 470n electrolytic cap (C23 round circle) -- where can I find one? This value seems not possible.


----------



## chongmagic (Feb 6, 2020)

bengarland said:


> *Here's another one:*
> 
> The Backfeeder board shows a 470n electrolytic cap (C23 round circle) -- where can I find one? This value seems not possible.



It is possible, here is one at Mouser:



			https://www.mouser.com/ProductDetail/KEMET/ESL474M063AC3AA?qs=sGAEpiMZZMtZ1n0r9vR22e66vF2fXFUF8kme3qJ3Z2UKgaHP5M6rCw%3D%3D


----------



## Robert (Feb 6, 2020)

bengarland said:


> The Backfeeder board shows a 470n electrolytic cap (C23 round circle) -- where can I find one? This value seems not possible.



You'll have better luck searching for 0.47uF (same thing).   0.47uF wouldn't fit on the silkscreen, and if it was marked .47u the decimal would be nearly impossible to read and _surely _a 47uF would end up there.


----------



## bengarland (Feb 6, 2020)

Ohhh... now I see. I'm terrible at searching on Mouser, but I'm getting better thanks to the help around here


----------



## zgrav (Feb 6, 2020)

it can come in handy to have a chart that lists equivalent values for capacitors in pf, n, and uf.  
take your pick:  https://www.google.com/search?rlz=1...nAhW7knIEHVQlBG0QsAR6BAgKEAE&biw=1295&bih=791


----------



## Nostradoomus (Feb 6, 2020)

I know what I’m looking for and still find Mouser hard to navigate!


----------



## chongmagic (Feb 6, 2020)

Navigating Mouser is indeed a nightmare.


----------



## Barry (Feb 6, 2020)

I find Digi-key easier to navigate


----------



## Nostradoomus (Feb 6, 2020)

Barry said:


> I find Digi-key easier to navigate



1000%


----------



## kApTcHa (May 9, 2020)

I Know I'm super late to this thread, but just wanted to say thanks because the info helped me confirm the info I found. Link is to a quick conversion chart! Cheers!






						Capacitor uF - nF - pF Conversion Chart
					

Capacitor uF - pF - pF Conversion Chart to help you convert between uF(MFD), pF and  pF(MMFD) as you read schematics, repair radios and shop for capacitors.



					www.justradios.com


----------



## MightySmallElectrons (May 9, 2020)

bengarland said:


> Ohhh... now I see. I'm terrible at searching on Mouser, but I'm getting better thanks to the help around here


Almost all of us have been through this...smart to ask questions.


----------



## bschobs (May 9, 2020)

So I’m actually coming to prefer mouser’s search because it’s so specific. One thing I haven’t figured out is whether or not they have low profile electrolytic caps. What value/value range would I put for that and in which filter?


----------



## Nostradoomus (May 9, 2020)

All your normal search filters but then filter by height as well. Many low profile electros are about 5mm tall so click a few filters around 5-7mm and see what you get.


----------



## bschobs (May 9, 2020)

Thanks again. I’m still pretty much a noob but starting to fill in a lot of blanks. I’ve got a couple of successful builds under my belt and a bunch of builds lined up. Working on making them look good which is almost an entirely separate hobby in itself... really enjoying all of it.


----------

