Author Topic: 1206 footprint  (Read 1795 times)

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Offline AztlanpzTopic starter

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1206 footprint
« on: October 24, 2018, 11:31:48 am »
Is there a difference from a 1206 footprint for a resistor versus a capacitor?
 

Offline jct

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Re: 1206 footprint
« Reply #1 on: October 24, 2018, 01:01:33 pm »
I've been using the same footprint for both, no problems experienced during flow soldering.
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Offline T3sl4co1l

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Re: 1206 footprint
« Reply #2 on: October 24, 2018, 02:32:18 pm »
There doesn't need to be, no.

If there is, it's usually that the capacitor has wider pads, or less pad gap, owing to the less-well-controlled tolerances on the end cap metallization, and the fact that it wraps around.  Whereas resistors almost never have wrap-around metallization, but curled around the ends, so there is never a side fillet.

Beware of specialty resistors, often low value current sense / shunt types for instance, have differently shaped ends, and will benefit from much less pad gap, or side fillet, or etc.  (Also consider heat sinking methods for power resistors, which having somewhat larger pads helps with.)

Refer to IPC-7351 (old versions are available free online) for terminology and how to calculate fillets, pad sizes and all that.  It varies with lead and package type, but the most common are easy to remember. :)

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Offline BocaDev

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Re: 1206 footprint
« Reply #3 on: October 25, 2018, 12:16:05 am »
Quote
Is there a difference from a 1206 footprint for a resistor versus a capacitor?

I use the standard 1206 footprint for both. To help our assembly people if the board will be hand soldered, I place a silk screen R or C in the center of the footprint, just large enough to read. Assembly says it does help them to differentiate between a chip capacitor or resistor.
 


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