From: Spehro Pefhany <speff@interlog.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Mon, 1 Mar 2021 11:26:48 -0800
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At 01:59 PM 3/1/2021, you wrote:
>That's fine for a one-off, but for a commercial product, today's=20
>efficiency requirements pretty much consign line frequency wallwarts=20
>to the history books.
>
>Even for one-offs, when I need + and - 15V now, I use a $7 Tri-Mag=20
>30V wallwart switching supply and rail-split inside the device using=20
>a spare opamp section or two. Another bonus to doing it this way is=20
>that it saves you from needing any voltage regulators.
>
>Friendly regards, Bob

The medical standard switchers are pretty acceptable for precision=20
work these days.

Thank goodness, there's probably not enough market in precision=20
instrumentation.

--Spehro





--=20
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