Hello there i am building a variable power supply as a summer project. I have ordered some parts, and want to begin building it. I start with the transformer power supply:
I've ordered a transformer (230 V – 36 V) and i expected it to give a output voltage of 36 V peak (silly me), and then found out the output will be in RMS, i. e. an peak outout of 50,92 V. I can work with this, but the capacitors i've orderes is only rated at 50 V, so this will give me some smoking problems i guess. The rectifying diodes will give a voltage drop of minimum 0,6 V, which is not quite enough to go under 50 V.
Is it possible to just use two diodes extra? As seen in the simulation:
The diodes added is of course D5 and D6. Their only purpose is to lower the voltage, to under 50 V. This will theoretical be enough.
But will i need to go lower in voltage, as the overhead on the WV of the capacitor is too small?
And is the "extra diodes" way even a viable way of doing this?
Best Answer
As a rule of thumb, it is always desirable to select capacitors which are 1.5 times (2times is even better) the desired voltage. So, in short, the answer is NO. Theoretically(ideally) it should, but practically it will be a bad design. An Even slight increase in input voltage or any small variation in the circuit than ideal and you might see the circuit smoked.