INA240-Q1: Questions regarding replace INA282 by INA240

Hi Wei-Hao,

 Here are my answers to your questions about INA240 and INA282:

 (1)   You can leave INA240 NC pin floating, there is internal weak pull down on this pin. 

(2)   1nF is the maximum allowed external load. It is OK to have 1K Ohm and 10nF, however this sets the bandwidth at 16KHz. The signal better be limited to no more than a couple KHz to maintain signal integrity.

(3)   Eyeballing the INA282 datasheet curves to get ballpark numbers - the SR is about 0.3V/uS; and settling time is about 6uS. You should do the same to see if you agree with these numbers. Unfortunately there is no recorded data for, say, 0.1% settling time.

(4)   It makes no difference for INA240, because the noise density is flat from DC all the way up to 200KHz.

 Regards,

Guang-Apps CMS Products

Hi Guang,

Thank you for your feedback, one additional question. What is the CMR production distribution for INA282? Customer wants to see this data.

Below is the CMR production distribution for INA240. 

Hi Wei-Hao,

There are no similar plots readily available for INA282. I could possibly generate a histogram for CMRR however not for drift. 

Out of curiosity, what is the reason behind this particular request?

Regard, Guang

Hi Guang,

Thanks for your reply. The CMRR histogram will be sufficient. Customer is having output accuracy issue with INA282 under different common mode voltage during the production phase, which they want to know distribution of the CMRR in order to estimate how much % of unit will fail the spec during the production.

Thanks.

Best Regards,

Weihao