Other Parts Discussed in Thread: INA333
Hello to everybody.
We are users of INA333.
The device is used, in large quantity, in EEG amplifier (64 units per device).
We noticed that parts marked on the bottom as W4EE suffer from instability in large percentage (>10%). We need to replace defective parts with units of different lots (e.g. W4XN, which is apparently better).
The instability seems related to the offset compensation circuit as an audible fleeble tone (armonic rich) is present in the output. The tone changes dominant frequency if a finger approaches the component (capacitive coupling?).
These parts suffer also from other problems: they are too sensitive to EM, compared to neigbohood amplifiers. And this puzzled me as I expected improved performances.
The replacement of the part removes all the problems.
Does someone else experienced the same effects?
Thanks, Gianpietro
