Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uunet!mcsun!ukc!tcdcs!unix1.tcd.ie!mckillnm From: mckillnm@unix1.tcd.ie (Bubble Boy) Newsgroups: sci.electronics Subject: 12 to 9 volts dc Message-ID: Date: 4 Mar 91 10:56:46 GMT Sender: news@cs.tcd.ie Organization: Trinity College, Dublin Lines: 58 Nntp-Posting-Host: unix1 Why don't U use the LM318 voltage regulater or even a 7809 regulater. Why not try this :- (7809) ____________ 1| 7809 |3 +12 V -------------------| |------------------ +9V | ------------ | | |2 | ------ | ------ ------ | ------ 100uF | | | 10nF | | | 0 V ------------------------------------------------- GND or this :- (LM318 ) ------------ 1| LM318 |2 + 12 V -----------------| |------------------ +9v | ------------ | | | |3 \ R2 | ------- | / ----- ======= |-/\/\/\--| ----- 100uF | | R1 | 10nF | | | 0 V ------------------------------------------------ GND As I sit here I can't think of the relationship between R1 R2 and the Vout (ie 9V), but any book on power supplies should have it in. If you can't find it mail me and I'll look it up for U. Hope this has been of some help !! Mark at unix1 TCD Dublin, Ireland. -------------------------------------------------------------------------- If it does not work :- |\/\/\/| | | ___________________________ | | / \ | (o)(o) | Don't have a cow, man !! | C _) \___________________________/ | ,___| __/ | / /____\ / \ +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++