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From: strong@tc.fluke.COM (Norm Strong)
Newsgroups: sci.electronics
Subject: Re: NEGATIVE VOLTAGE?
Message-ID: <1991Mar12.174440.26009@tc.fluke.COM>
Date: 12 Mar 91 17:44:40 GMT
References: <1991Mar8.140031.20095@uncecs.edu>
Organization: John Fluke Mfg. Co., Inc., Everett, WA
Lines: 19

In article <1991Mar8.140031.20095@uncecs.edu> crisp@uncecs.edu (Russ Crisp) writes:
}
}Hello.
}
}I'm in the midst of a construction project that, when complete, will
}require a -12 volt power supply, a +5 volt, and a +12 volt supply.
}I can handle the +5, and the +12, but the -12 is vexing me.  Can
}I use another independent 12 volt supply, and reverse the leads, or
}would this be a fire hazzard?  Whats the scoop on negative voltage
}power supplies anyway?

If you don't need more than a few milliamps, the  best solution is a Maxim
IC called the MAX636B.  It converts 5volts directly into -12volts at up to
50ma.  

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA