Make A Curve Tracer For Your Lab - Part2: Power Supply

[@we-are-electric1445]

Can anyone explain exactly why diodes D1,D2,D3 and D4 are necessary ? Why should the voltages across C5,C6,C7 and C8 cause a problem for the bridge rectifier ?

[@eleneasy]

Not for the bridge rectifier, but for the regulators. When you turn off the power supply, you will have charged capacitors on the right side of the regulators, providing the same voltage as the output. On the left side of the regulators, instead, there is 0V. The regulators will find themselves polarized inversely with possible damage to them. The use of the diodes is suggested by the regulators data sheets to prevent that kind of damage.

[@we-are-electric1445]

@@eleneasy Thanks. I see it now. It's a long time since I did any circuit theory but it's all starting to come back to me now !

[@BichaelStevens]

Pretty please improve your thumbnail game It looks like those "jraphic art is a my passion" memes