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I am working on a digital voltmeter circuit using ICL7107 IC. Having trouble powering it up. There is a -5 V supply to pin 26. I used a 7805 regulator for +5V supply but wondering how to supply the -5V. a) Can I use the output of 7805 to somehow convert to negative? b) is there an IC for this?( my max current rating is 3.34Amps). Note: I tried using 7905 with 7805 but no use the 7805IC goes burning hot. As soon as I removed the connections between two it behaved properly(only7805). Please suggest some idea to achieve this.