[time-nuts] Switching regulator replacement for 7805

[jimlux]

On 12/4/16 12:14 PM, John Ackermann N8UR wrote:
> That's a very good point... the design I'm testing the regulator in has
> a fair bit of C filtering, but no series L.
>

I little series L and another C (so you have a pi low pass) can make a 
huge difference.  If the load current is reasonably constant, then the 
drop across the series R of the L will be constant, so you can bump the 
dc/dc output to compensate.  It's pretty easy to get 60dB of rejection 
from a C-L-C pi, and for 2MHz, the parts are physically small.