Re: Pi PICO W on batteries

From	The Natural Philosopher <tnp@invalid.invalid>
Newsgroups	comp.sys.raspberry-pi
Subject	Re: Pi PICO W on batteries
Date	2026-06-24 13:53 +0100
Organization	A little, after lunch
Message-ID	<111gk0e$30bc0$7@dont-email.me> (permalink)
References	<110m2k5$3hv5p$5@dont-email.me> <n9avpnF383nU1@mid.individual.net> <110pjo1$jklg$1@dont-email.me> <sm0se6c8n2s.fsf@lakka.kapsi.fi> <97F*HqVJA@news.chiark.greenend.org.uk>

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On 24/06/2026 13:41, Theo wrote:
> Anssi Saari <anssi.saari@usenet.mail.kapsi.fi> wrote:
>> The Natural Philosopher <tnp@invalid.invalid> writes:
>>
>>> On 15/06/2026 19:49, Brian Gregory wrote:
>>>> nano timer ??
>>>> What's that then?
>>>
>>> TPL5100
>>>
>>> https://www.ti.com/product/TPL5110
>>
>> I kinda thought modern microcontrollers have this sort of thing built
>> in? Oh, looks like the Pico (no W) draws 2 mA in "deep sleep" and this
>> timer draws 35 nA.
> 
> That does sound surprisingly bad for the Pico.  Seems that the RP2040 is
> 0.18mA in 'dormant' (ie deep sleep) and 0.38mA in 'sleep', which is a bit
> better.  So must be something else on the Pico that's not so good in sleep
> mode.
> 
The broadcomm wifi chip.

> If you've got other stuff hung off the MCU that isn't super low power,
> you're going to have to power-gate it anyway, in which case the nano timer
> will do that at the same time.
> 
Indeed. I have an ultrasonic unit.

I looked at every combination I could think of, and ended up with the 
nano timer after trying to construct my own in analogue.

I can say that the three lithium primary cells plus the nano timer (MUST 
have a BIG electrolytic on its back end or it goes unstable) is THE very 
best way to have a periodic remote sensor 'phone home' if a cable can't 
be laid



-- 
I would rather have questions that cannot be answered...
...than to have answers that cannot be questioned

Richard Feynman

Thread

Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-14 12:17 +0100
  Re: Pi PICO W on batteries rbowman <bowman@montana.com> - 2026-06-14 17:48 +0000
    Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-15 12:31 +0100
      Re: Pi PICO W on batteries John R Walliker <jrwalliker@gmail.com> - 2026-06-15 13:04 +0100
        Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-15 13:17 +0100
      Re: Pi PICO W on batteries "Peter Heitzer" <peter.heitzer@rz.uni-regensburg.de> - 2026-06-15 12:06 +0000
        Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-15 13:19 +0100
          Re: Pi PICO W on batteries "Peter Heitzer" <peter.heitzer@rz.uni-regensburg.de> - 2026-06-15 13:58 +0000
            Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-15 16:52 +0100
    Re: Pi PICO W on batteries mm0fmf <none@invalid.com> - 2026-06-15 12:52 +0100
  Re: Pi PICO W on batteries Brian Gregory <void-invalid-dead-dontuse@email.invalid> - 2026-06-15 19:49 +0100
    Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-15 20:28 +0100
      Re: Pi PICO W on batteries Theo <theom+news@chiark.greenend.org.uk> - 2026-06-15 20:54 +0100
        Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-16 01:59 +0100
      Re: Pi PICO W on batteries Anssi Saari <anssi.saari@usenet.mail.kapsi.fi> - 2026-06-24 09:33 +0300
        Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-24 09:58 +0100
        Re: Pi PICO W on batteries Theo <theom+news@chiark.greenend.org.uk> - 2026-06-24 13:41 +0100
          Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-24 13:53 +0100
          Re: Pi PICO W on batteries "Peter Heitzer" <peter.heitzer@rz.uni-regensburg.de> - 2026-06-24 14:51 +0000
            Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-24 16:41 +0100
              Re: Pi PICO W on batteries wmartin <wwm@wwmartin.net> - 2026-06-24 20:35 -0700
                Re: Pi PICO W on batteries John R Walliker <jrwalliker@gmail.com> - 2026-06-25 09:21 +0100
                Re: Pi PICO W on batteries The Natural Philosopher <tnp@invalid.invalid> - 2026-06-25 10:12 +0100

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