Thread: Questions on Sproggy's mk2 power supply

What are the characteristics of the MBR745
Zener diode? (volts, current).

45 volts of stand off (reverse bias), 7.5 amps, 0.5 volts forward voltage. Search on www.digikey.com for a data sheet or to order. Costs about 65 cents.

What are the current ratings on the 47uH and 20uH coils?

Chances are they are rated for more than 5 amps seeing is that is the output current.

14 to 16 gauge wire should do the trick. You can wind your own if you wanted.

Also what does the 20uH coil do?

It isolates the feed back loops of the regulators. That way one regulator does not try to compensate for the other regulator.

If you got the adjustable version, you could set the output voltage to 5.5 volts and then use another of the 0.65 cent MBR745 diodes in its place. You might have to tweak it to get it to work symetrically.


All of these questions reference half of the 5volt section.

What I am trying to do is find equivalent parts for replacement.

GO to www.national.com and go to the analog power supply section. They have similar switches.

Jeff_