A linear IC with DC Input Offset measured between the + and - inputs should be no greater than lOmV apart or device is faulty.
POWER SUPPLY SUBASSEMBLY TROUBLESHOOTING Troubleshoot the power supply subassembly using the circuit description. Note that voltage levels displayed on the schematic diagrams are not absolute values as reari jus may vary between units. Once the probl#Uls localized, check the .suspected part by direct substitution if possible. Otherwise, use a voltmeter or oscilloscope to determine the malfunctioning part. Note the color code on the power supply schematics: +15V (red), -15V (black), 45V (yellow), ground (green).
Note in the accompanying diagram a typical IC used in a linear mode with negative feedback.
CMOS IC's usually fail by latching the output(s) and getting hot to the touch.
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