When I simulate any current pump - a standard improved Howland for example - and use the provided model for LM3886 then the S/N reports ca. 40dB lower than when using any other TI opamps. For example (LM3875 - belonging to the same Overture family, but also OPAs high voltage high current, or small signals, LM's etc).
On my simulations I use the same topology and exchanging only the active power element (changing Vs as needed). I also compared inverted with non-inverted configurations.
Funny thing, when simulating Voltage source amplifiers then the S/N behaves in trend with all other
I double checked LM3886 and LM3875 in LTSpice, same results. There I could also compare with LT chips too. The only exception to the S/N trend apparently isLM3886.
I need to know if anyone can confirm this is indeed the true behavior of LM3886 with current pumps... or is just a Model glitch. If the later is true, what is your suggestion to solve the problem? Without proper simulations results I cannot consider to propose designs using LM3886. The TI announcement that LM3875 is obsolete does not help either, on the contrary - buying stock of obsolete parts is what I would strongly avoid.
TI's customer support cannot address this directly, but suggestion was to run this question on the TI E2E forum or via resellers. Because this is still evaluation phase, and I do not like to discuss quantities right now, I prefer the Forum.
Thanks,
Ion
