The output of the first optoisolator's emitter voltage is fed back to the
inverting electrode of the opamp. The output of the emitter of the second
optosolator's transistor will be a voltage that exactly matches the
input voltage -->applied to the non-inverting electrode of the opamp.<--

Fr. Tom McGahee

-----Original Message-----
From: PDRUNEN@AOL.COM <PDRUNEN@AOL.COM>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Wednesday, March 08, 2000 6:15 PM
Subject: Re: [OT] 4N35 OPTO as analog isolator


>In a message dated 3/8/00 5:21:18 PM EST, tom_mcgahee@SIGMAIS.COM writes:
>
><< The output of an opamp is connected via a 47 ohm resistor to the Anode of
> the first optoisolator LED. The cathode of the first optoisolator LED is
> connected
> in series to the Anode of the second optoisolator. The cathode of the second
> optoisolator LED is connected to ground.
>  >>
>
>Thanks Tom,
>
>But I failed to see where the analog input signal is applied.
>
>Paul
>