Skip to content

Comment on Silicon die analysis: inside an op amp with interesting “butterfly” transistorsparent

Comments

usually power

That may be true but I'm not sure it applies in this context. Another valid reason is because at a larger scale it is easier to get the dimensions to be within a fairly close tolerance of the counterpart and hence to get two parts that function well in tandem.

Matched pairs and current mirrors are exactly the right situations for this and so they tend to be oversized, even if that slows the parts down considerably.

Also, the input stage is where noise figure is critical. Larger transistors are lower noise figure.

AboutSource Built by g1lg1l

Hackerly is an independent reader for Hacker News, built on the public HN API. Not affiliated with Y Combinator.