gEDA-user: Switching regulator question

[DJ Delorie]

> I looked briefly at LC filters to handle 120Hz ripple.  Requires some
> pretty large, expensive inductors if I'm not mistaken.  Seems cheaper
> in both board space and money to have more capacitance.

Are you trying to filter the 120Hz ripple, or just block the switcher
ripple?  Using a small inductor between the bulk caps (120Hz side) and
a tantalum (switcher freq) "bypass" cap might help protect the bulk
caps from too much high frequency ripple current.

/me wonders if a diode in series with that inductor would help prevent
resonance?