); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY David Forbes wrote: > At 9:09 PM -0600 11/1/07, [EMAIL PROTECTED] wrote: > >> It is funny how things you forgot a long time ago have a way of coming back. >> >> Case in point. I was just running some simulations on the EFC >> interface and then I had this idea. >> >> Wouldn't an instrumentation amplifier be the right way the isolate the >> Fury EFC voltage? >> >> For instance, the Burr Brown INA 103. It would provide for isolation >> as well as gain. Not sure of all the details yet. >> >> I remember using this device for a thermocouple a few years back. And >> I even managed to find a few of them in a box somewhere. >> > > The AD620 or LT1167 is a fine little instrumentation amp. 8-pin > package. Very easy to use, good specs. > > > AD620 is quite noisy at low gains as is the LT1167. For this application with a 5V EFC range from the Fury a gain of 2X is all thats required for an HP10811A. For a 20V (-10V to +10V) output EFC swing a gain of 4 is sufficient. Since these devices use an external gain setting resistor, gain tempco may be higher than desired. Using the 10811A(or 10544A/B) EFC ground pin to remotely sense the ground on the circuit board will minimise the effect of voltage drops across the 10811 connector. >> There is no question that he TL431 is not right here. I am already >> running the simulation with an LM128 or such. PSPICE only has the >> LM128 so I am just testing this out. >> >> -George >> > > The REF19x series is very good at this sort of job. Also 8 pins. > > These are relatively noisy devices.
Bruce _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
