LMC6482: The replacement device for LMC6482

user4674678,

It would be very helpful if you specify most critical parameters like minimum bandwidth, quiescent current, etc. for each op amp to narrow down the selection. There is no dual option for the lowest IB op amps. You ask for a replacement of LMC6482 (max IQ of 1.4mA) and LT6000 (max IQ of 16uA) but they are vastly different in terms of speed the current consumption (100x) so is the quiescent current and speed important or not?
If I do not try to make overall sense of your selection, I would suggest you take a look at LMP7721 in the same package as LMC6482 but with max IB of 20fA and max Vos 180uV vis-a-vis LMC6482 IB of 4pA and Vos of 750uV, respectively. Likewise, please check OPA379 with IQ of just 3uA and SOT23-5 package - Vos of a second stage should not matter as much as the offset of the first stage. If IQ is not important but Vos is in fact critical, please take a look at OPA388 or OPA376 (in SOT23-5 and VSSOP package, respectively).

Hi Marek,
Thanks for your reply.

Q1: The package of LMP7721 is two large. Is there any other smaller package device and can replace LMC6482 and LT6000?
The bias current of OPA379 is 50pA. It is higher than LMC6482. And the bias current of OPA388 is also than LMC6482.

Q2: For OPA376. I cannot get the bias current from figure 11. I want to know the max bias current of OPA376 when the temperature is
at -20C and +50C. Because our product will work from -20C~+50C.

Hi Marek,

Can you continue to help me?

Please check the following parts but none of them come in a tiny package:

Fig 11 in OPA376 datasheet shows the typical input bias current over temperature; since the typical IB at 25C is 0.2pA and the input bias current is caused by the reverse-biased leakage of ESD protection diode, it doubles every 10 deg C.  Therefore, at 50C the typical IB current will be: 0.2pA*2^2.5 = ~1.13pA.  We do not test the input bias current over temperature in the final test but I would expect the max IB to be less than 10pA at 50 deg C.