Hi,

I need to design a power supply circuit with the following spec

1) AC input 120-240V AC 50/60Hz or +-48V DC
2) DC output 24V at 1.5A

I know the normal part that 240VAC to 24VDC using transformer, rectifier, filter and Linear regulator using LM317.
Buy I need help regarding how to convert +-48DC to 24V DC.

Looking forward to ur help!

Thanks.

 

Well, you could use the same bridge rectifier, and put the resulting ~46VDC into a DC-DC converter.

 

Sorry, I dont actually get u. Could u post a rough circuit.
Thanks

 

Sorry, I dont actually get u. Could u post a rough circuit.
Thanks

I don't have a circuit. But you can have a look at suppliers like National Semiconductor. Their "Webench" will give you a circuit. Input DC volts 25V to 50V (give some error on both ends), output voltage 24V at 1500mA.