LPC553x Op Amp Is Instrument Grade With 5mV Offset?

[mikenn]

What's up NXP,

I am interested in LPC553x to transduce an unconditioned strain gauge with 2 mV/V output to ten bit accuracy.  LPC553x contains substantial a/d, vref, and op amp resources, with the latter touted as "instrument grade".  When I examine the op amp data, however, input offset voltage is listed as +/- 5mV which is not suitable for instrument amplifier specification.  There is allusion to an offset cancellation facility, but in my experience this would not remove enough of the listed voltage offset to render this part usable in my application.  In summary, how does a 5mV offset op amp get "instrument amp" status?  What am I missing?

[EdwinHz · Accepted solution]

Hi @mikenn 

I don’t believe there is anything particular that you are missing. The information from the datasheet is correct and the LPC553x can also be adjusted with improvements from the offset cancelations as you mention.

Please let me know if you have any further inquiries about the LPC553x.

BR,

Edwin.