Usually I can get by with jelly bean amps but not this time. Offset should be well under 1mV but most of all the input noise must be under
5nV/sqrtHz. Supplies +/-15V, TSSOP or SOIC, quad package. The OPA4227 fits the bill nicely with plenty of margin. Then came the awakening: Out of stock at Digikey and Mouser. Same for its faster brother, the OPA4228. Big red flags went up.Could the OPA4227 be falling from grace for some reason? If you know what replaces it I'd appreciate a hint. I am looking around myself now but want to pick something that's going to be around for a couple of decades.