From: Neil <picdude3@narwani.org>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Mon, 27 Apr 2020 12:43:34 -0700
Subject: Re: [EE] Voltage regulator with high input voltage
Thread-Topic: [EE] Voltage regulator with high input voltage
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Gotcha.

One more question -- does the 270-ohm resistor need to be that low. If=20
he's dropping from 40V to 8.2V, that resistor will need to be high=20
wattage.  Shouldn't a much higher value work here?

Cheers,
-Neil.



On 4/27/2020 3:08 PM, Isaac Marino Bavaresco wrote:
> Neil,
>
> V+ is an output to other circuits that use unregulated voltage.
>
> Cheers,
>
> Isaac
>
>
>
>
> Em 27/04/2020 15:45, Neil escreveu:
>> Isaac,
>>
>> What's the purpose of V+ in this?
>>
>> Cheers,
>> -Neil.
>>
>>
>>
>> On 4/27/2020 2:36 PM, Isaac Marino Bavaresco wrote:
>>> Something like the image below.
>>>
>>> Change the Transistor, Zener, capacitor and resistor to your needs.
>>>
>>> Cheers,
>>>
>>> Isaac
>>>
>>>
>>>
>>> Em 27/04/2020 14:24, David C Brown escreveu:
>>>> I am designing a current monitor for my e-bike.  Using an INA169 hi si=
de
>>>> 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 whi=
ch is
>>>> nominally 36v but can rise to over 40 volts when fully charged.  Most =
small
>>>> linear regulators seem to be rated at 36v..
>>>>
>>>> Current would be a couple of milliamps with the display off (most of t=
he
>>>> 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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