How to make a regulated power supply with different dc output?

[ymx]

Hi all,


We have a school project in our Electronics Analysis and design. But our group doesn't know how to start with it and we need it to pass this week. Kindly teach us to make it with PCB design and how to make its schematic design? We should get a regulated 1.5, 3, 4.5, 6, 9, and 12 volts dc output. Thank you very much!

 

[Hero999]

Try the LM317, a transformer, ectifier and filter capacitor.

 

[ymx]

Thanks for the answer sir! My group mate had already went to an electronic technician. The technician used a bridge rectifier 1N4001, Hr1061, 220 micro farad 1000 micro farad capacitors, 6 zener diodes of 3.3, 4.3 for 4.5, 6, 7.5, 8.7 for 9 and 12. volts and voltage selector. Our input voltage is 12 voltage from ac transformer.

 

[Hero999]

Why not use the LM317 and put the the voltage selector switch on the potential divider?

A Google image search returns a similar circuit to what you need on the third hit. It's easy to modify it to give the voltages you need. You'll need a higher voltage transformer than 12V to reliably get 12V out: 15 V should do.

http://www.eleccircuit.com/lm317-linear-power-supply-regulator-selector-15v3v45v5v6v9v-15a/
https://www.google.co.uk/search?client=opera&q=LM317+regulator&oe=utf-8&channel=suggest&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=mngKUeTCBcqp0AWVwIDoDw&biw=1920&bih=927&sei=u3gKUeaYGou10QWLs4D4Dg