[sdiy] SMT diodes: MELF vs. SOT-23 chip?

[rsdio at audiobanshee.com]

On Sep 23, 2015, at 11:38 PM, Mattias Rickardsson <mr at analogue.org> wrote:
> When shopping for singles, MELFs do show up as the least expensive alternative. But duals can often be used, and then the SOT-23 chips come in.
> 

Ah, yes. I used a ton (41) of the dual, common cathode diodes in SOT-23 for the Ohm64 design. This works great in a button matrix, but MIDI and other circuits don't always work with common cathode or common anode configurations.

I recently went looking for higher density common node diode packages, but the 8-diode arrays are way more expensive. They must be something special. Larger 12, 16, 24, and 32-diode arrays are almost $4 each!

The quad NXP 1PS88SB48 (SOT363) is maybe 4 cents per diode, and the hex Diodes Inc SDM6CC-7 (DFN-6) is maybe 5 cents per diode. Those aren't really much of a savings in price versus singles, but they reduce traces when used for a scanned switch matrix.

Brian

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20150924/e5673e14/attachment.htm>