At 09:17 25.6.1998 -0600, you wrote:
>OK, I asked this once before, and got some good leads, but none of them
>worked out, and now its the 11th hour.
>
>I have a 2 wire instrument that is loop powered at 24 VDC (the current
>on the loop varies 4-20mA at 24 VDC depending on the output of the
>probe).  I need to monitor the loop and trip a relay at a certain
(adjustableurrent.
>
>Sure, I could design a thing with a series resistor and monitor the
>voltage with a couple of op-amps, but prefer an off the shelf solution.
>
>email direct hcooper@es.com
>

Check the MAX4172 circuit from Maxim. This IC should work for you.

Best reagards

PavelK

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* Pavel Korensky                                                         *
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* SUMMA SCIENTIA - NIHIL SCIRE                                           *
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