Part Number: TIDA-00440 Other Parts Discussed in Thread: LMC6082 , ADS1256 , Hi Team
I have a customer that is designing to measure leakage current in electric machinery insulation.
The requirement measuring current is approximately 1nA using the…
John,
The two op amps you mentioned are quite different - OPA140 is 36V op amp while OPA392 maximum supply voltage is just 5.5V; thus depending on the supply voltage, you may want to consider using 5V LMP7721 or OPA392, 15V LMC6082, and 36V OPA192…
Hi Arumugam,
The oscillation is created from op amp instability with large cap loading. See the LMC6082 datasheet on page 10 where it discusses CAPACITIVE LOAD TOLERANCE.
As your input filter resistors (R319-R329) are 0 Ohm, the op amp is directly…
Ron,
Thanks very much. I followed it to an LMC6082 that should do the trick. I've got a couple LM358 chips coming that I will try until I can get some LMC6082's to try.
Mike
Hello Paul
Thank you for your practical answer. It is very useful one.
I agree with you it is just a engineering quidance, but It will greatly help us to set spec compliance matrix.
I see 0.1pA as follows at http://www.ti.com/product/LMC6082/description…
Hello user3830479,
To replace the AD8667, check our OPA2187. OPA2187 is a Zero-Drift(check out the tech note here: http://www.ti.com/lit/an/sbot037a/sbot037a.pdf ) wide supply CMOS OpAmp that easily goes head to head with the competitive device and…
Hi Luis,
Thanks for your reply. Find the below snap on the RTD connection in amplifier circuit. Since Layout and PCB was manufactured; i am not interested to change the circuit .
I interest to change only the low offset opamp OPx317 instead of LMC6082…
Hello Pablo and Lothar,
I see that you are running the LM6171 from 9V single supply (VEE tied to ground). The input common voltage range of the LM6171 (VCM) does not include the VEE (or V-) rail. VCM requires at least 1.3V headroom to V- and to V+. …
Hi Faisal,
The OPA 4354 would have been ok, except that it has really high offset voltage .... 8mV which I think does not match your specs. There are a few Opamps that would match your requirements. The best one seems to be OPA4277 . However you could…
