40V dual power supply
Description.
This 40V dual power supply circuit was designed in response to a request made by Michael from Philippines. His application is to power the 150 Watt amplifier circuit published here. I think this power supply design is adequate for the purpose. The transformer T1 steps down the mains voltage, bridge D1 performs the rectification, C1 and C2 does the job of filtering.C3 and C4 are decoupling capacitors.
Circuit diagram with Parts list.
Notes.
- The T1 must be a 230V primary, 30-0-30V secondary, 200VA transformer.
- All capacitors must be rated at least 63V.
- C3 and C4 are polyester capacitors.
- If 8A bridge is not available, make one using diodes like P600A.



Would this be suitable for a stereo amp based on two of the 150W amplifiers or would two separate power supplies be required? Cheers
In order for this supply to be used for two 150W amps – left and right – would it be necessary to increase the VA of the transformer – if so – by how much? Cheers
yes, the power supply ratings must be doubled.
two seperate power supply will reduce noise, but it is very costly.
Here a single power supply with double ratings is enough for stereo mode.