[sdiy] Gates and Triggers

[David G. Dixon]

> Just curious, why aren't you using the 7805 rather than the 78L05?
> I never use 78Lxx/79Lxx for my DIY projects, no matter how little
> current they draw. 78xx are so cheap, and need only little more space.

I like using the smaller chips.  Plus, according to the datasheet, 78L05 can
source 100 mA.  The entire keyboard scanning circuit (which is all low-power
CMOS chips) draws only a small fraction of that, so there is absolutely no
need for anything beefier.  I've applied the "fingertip test" to the 78L05
during operation, and I can detect no heat generation whatsoever, even after
an hour of continuous playing.