I'm designing a power supply with a 120V AC input and an output of 5V DC ..
I'm using an AC to DC step-down converter (RECOM RAC02-05SC) which outputs 5.6V instead of 5V
followed by a capacitor which should take out any ripples. (image attached) and a zener diode to limit the voltage to 5V.
the problem is my output signal is not exactly DC! it contains a periodic ripple of around 300 mV!
I tried increasing the capacitance across the output to about 1.2 F and that ripple still existed.
what is a good way of getting rid of that ripple?
also what would cause the zener diode to get really hot?
I'm very limited in circuit space so hopefully small size parts would do.
thanks in advance
I'm using an AC to DC step-down converter (RECOM RAC02-05SC) which outputs 5.6V instead of 5V
followed by a capacitor which should take out any ripples. (image attached) and a zener diode to limit the voltage to 5V.
the problem is my output signal is not exactly DC! it contains a periodic ripple of around 300 mV!
I tried increasing the capacitance across the output to about 1.2 F and that ripple still existed.
what is a good way of getting rid of that ripple?
also what would cause the zener diode to get really hot?
I'm very limited in circuit space so hopefully small size parts would do.
thanks in advance
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