Help requested for LM318

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From: Werner
Date: Tue, 29 Apr 2003 10:13

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Hi fellow electronics enthusiasts,

I'm trying to build a on/off detection circuit, which is able to check if
the connected LCD monitor TV is in standby mode (31 mAmps/12 volts) or
active mode (725 mAmps/12 volts). I have put a 0.3 Ohm resistance in series
with the 12 Volts DC power supply, so I have a small voltage drop across my
0.3 Ohm resistance, maybe enough to measure this drop using an LM311
comparator IC.

But I'm afraid that the LM311 might go into an oscillation state as the
voltage drop is small ... so I've thought about adding an LM318 (diff.
amplifier) in front of the LM311 to boost the voltage drop signal ... but I
don't seem to be able to get this to work correctly. Both LM's I would like
to power off the 12 Volts DC supply of the LCD monitor.

Can anybody suggest? How to wire it up?

Thanks a million,


Werner

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Subject: Help requested for LM318
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