From: Neil <picdude3@narwani.org>
To: "piclist@mit.edu" <piclist@mit.edu>
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Date: Mon, 27 Apr 2020 10:48:17 -0700
Subject: Re: [EE] Voltage regulator with high input voltage
Thread-Topic: [EE] Voltage regulator with high input voltage
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Since you say linear (from 40V -> 5V), I'll assume you're not too=20
worried about efficiency.
How about Inline diodes or resistor to drop 40V to under 36V, then regulate=
..
Or a zener pre-regulator?
Or another linear regulator with the ground offset?
Otherwise look at webench or similar for a switcher with a higher input=20
range.


Cheers,
-Neil.


On 4/27/2020 1:24 PM, David C Brown wrote:
> I am designing a current monitor for my e-bike.  Using an INA169 hi side
> current senor into a mid range PIC with a two digit LED display.
>
> Problem is getting the 5 volts for the PIC from the e bike battery which =
is
> nominally 36v but can rise to over 40 volts when fully charged.  Most sma=
ll
> linear regulators seem to be rated at 36v..
>
> Current would be a couple of milliamps with the display off (most of the
> time).  Nearer 100 with the display on..
>
> Any suggestions
>
>
> __________________________________________
> David C Brown
> 43 Bings Road
> Whaley Bridge
> High Peak                           Phone: 01663 733236
> Derbyshire                eMail: dcb.home@gmail.com
> SK23 7ND          web: www.bings-knowle.co.uk/dcb
> <http://www.jb.man.ac.uk/~dcb>
>
>
>
> *Sent from my etch-a-sketch*

--=20
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