Re: simple 150uA constant current supply


> Thanks Martin but, it's not homework, I don't have any space for an
> IC and this is battery powered. I can only spare about 30uA to
> 'generate' this supply.

There are microscopic nanopower opamps from Linear and others. Since all you want is nominal +/-20% , and this is the same as Vbatt ranging from 2-3V, then something simple that does not require much battery current would be like so, total bias around 16ua, compliance should be to within a few hundred millivolts of the rail, and you could do even better with a PFET:
View in a fixed-width font such as Courier.

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