[ARC5] BC-453-B Power Supply - voltage-multipliers

[Kenneth G. Gordon]

On 6 Apr 2023 at 12:54, Bob  Camp wrote:

> 
> Hi
> 
> The bigger the C, the better the regulation. How big you go depends on
> budget and load. Regulation goes down as multiplication goes up. With
> a fixed (say 10%) regulation requirement, the caps will get bigger and
> bigger as you go from 2 to 3 to .... 5 to 6X multiplication.
> 
> Also the bigger the total C, the higher the peak current through the
> diodes. This (obviously) is also load related. Usually best not to go
> too crazy on the caps, simply to allow cheap diodes to live a long and
> happy life.
> 
> Bob

Absolutely correct, Bob. Good on ya. 

Still, 30 mfd is, according to many older handbooks, the minimum capacitance which should 
be used for good regulation. 

Since, as I recall it (dangerous at my age) all the capacitors in a voltage-multiplying circuit are 
in series across the power transformer, one must calculate capacitances in series to arrive at 
the correct value of each to maintain that 30 MFD minimum.

I use Duncan Amps', PSU-Designer-II to check on those parameters, such as peak current 
through the diodes, in order to build such power supplies.

http://www.duncanamps.com/psud2/download.html

It is a very good little piece of software, is very easy to use, and is easily modified for about 
any power-supply circuit you might need.

Ken W7EKB