I'm modding my printer (why not!) So, I need to get some +12V in there.. The only problem is that when the printer sits idle, the PSU delivers 12V. But as soon as somethings starts happening, it jumps to 24V. Ok, dropping 24V to 12V is not hard, I could just throw in an LM317 with the right resistors. But what would then happen when the supply voltage drops to 12V? The specs say LM317 should have 1,5V higher supply then draw. Would the output just drop to 10,5V? A bit lower than 12V when in idle is ok, so other great ideas? Just mentioned the 317's since I've got some laying around here...
If you have the $$$ get a DC/DC converter with 10 to 36VDC input and 12V output. Google this for more info http://www.google.com/search?num=100&hl=en&lr=&q="wide+input"+dc/dc+converter+10+36 .
Looked at those, but that pricetag is WAY too much.. So I assembled a litte LM317 based regulator, it gives me about 11V when supplied with 24V and about 10V when supplied with 12V. Works fine, and the printer is still alive!
