Hello,
I am tweaking a design that uses a '7543 12-bit DAC and a LT1013 op amp in unipolar mode. Per the design sheet, the DAC is sensitive to the input offset voltage (Vos) specification. The recommendation is to use 1/10 of an LSB as a threshold for Vos. The DAC uses both a -1.1 and -5.4 Vref so the worst case is the -1.1 Vref case where the resolution is 1.1/4096 or ~269uV. So that means the op amp Vos max would be 1/10 or ~27uV. I was trying to find a part that was an 8-pin dual amp SOIC package, Vcc-Vee >
22V, Vos max < 27. The amp is only used for DC signals. So far the closest I found is the OP2177. Granted, its max Vos is 75uV but typical is
15uV. So that in mind...
1) Does anyone have any idea about distribution around typical for AD amps? (I have a feeling this is impossible to determine!)
2) Does anyone know of some other parts to consider (I am trying to keep in a 8 SOIC dual or quad amp package and I do realize there are some single amps that are better).
3) Other recommended amps to consider.. I have the AD8672 under consideration as well.
The hang up on the parts I have so far is basically the Vosmax specification.
Thanks!