On 2022-06-12, boB <boB@K7IQ.com> wrote:> On Sat, 11 Jun 2022 21:04:41 -0000 (UTC), "Don" <g@crcomp.net> wrote: > >> Many consumer grade USB power banks come with a built-in >> automatic shutdown circuit. Light loads, such as the nominal >> 6.8 ?A drawn by a portable MP3 player, are not enough to >> prevent shutdown. To compensate, this project uses >> a 555 to nominally pull 100 mA every 5.5 seconds. >> >> ( excerpt - read more at https://crcomp.net/mp3mod/index.php ) >> >>Danke, > > > forgot the 'u' in microamps.He used a mu symbol, just your newsreader apparently can't handle the way he did that. -- Jasen.
Power Bank Keepalive
Started by ●June 11, 2022
Reply by ●June 17, 20222022-06-17
Reply by ●June 18, 20222022-06-18
On Saturday, June 11, 2022 at 9:04:48 PM UTC, Don wrote:> Many consumer grade USB power banks come with a built-in > automatic shutdown circuit. Light loads, such as the nominal > 6.8 μA drawn by a portable MP3 player, are not enough to > prevent shutdown. To compensate, this project uses > a 555 to nominally pull 100 mA every 5.5 seconds. > > ( excerpt - read more at https://crcomp.net/mp3mod/index.php ) > > Danke, > > -- > Don, KB7RPU, https://www.qsl.net/kb7rpu > There was a young lady named Bright Whose speed was far faster than light; > She set out one day In a relative way And returned on the previous night.Hello Don, you're obviously a handy guy, so why not just open up the power bank, and bypass that 'auto-shut-off' circuitry? Maybe you use this power back for other uses? So you still want the auto-shut off? I don't see the logic why that feature is needed in the power bank, anyway. Any electronic device (beyond a simple thing like a light) is likely to have its own auto-shut -off function. But you do want to preserve it, then I'd install a simple SPST switch to select bypassed- or native-behavior as you like. cheers, Rich S.
Reply by ●June 19, 20222022-06-19
Rich S wrote:> Don wrote: >> Many consumer grade USB power banks come with a built-in >> automatic shutdown circuit. Light loads, such as the nominal >> 6.8 μA drawn by a portable MP3 player, are not enough to >> prevent shutdown. To compensate, this project uses >> a 555 to nominally pull 100 mA every 5.5 seconds. >> >> ( excerpt - read more at https://crcomp.net/mp3mod/index.php ) > > Hello Don, you're obviously a handy guy, so > why not just open up the power bank, and > bypass that 'auto-shut-off' circuitry? > > Maybe you use this power back for other uses? > So you still want the auto-shut off? > > I don't see the logic why that feature is needed > in the power bank, anyway. Any electronic device (beyond > a simple thing like a light) is likely to have its own auto-shut > -off function. > > But you do want to preserve it, then I'd install a simple > SPST switch to select bypassed- or native-behavior > as you like.One reason for me to leave the Power Bank unopened is it may open a can of worms. Especially if it uses an undocumented, expoxied, exposed-lead chip to control its charge cycle /and/ perform an automatic shutdown. Also, my tear-down of the MP3 player to remove its battery and USB-B port already sated my appetite to take things apart (for now). :) You didn't comment on my MP3 player. Muchas Gracias. After all, the player's merely an available adjunct to test my keepalive with a field trial. Although the keepalive functioned as originally intended, the prospect to double its efficiency tempted me to replace R2's original 150 K ohm value with a 300 K ohm. So my page now reflects R2's new value: <https://crcomp.net/mp3mod/index.php> The keepalive successfully functions on two distinct Power Banks with different capacities, marketed under separate brands. Besides auto- shutdown, both Power Banks also share similar design language [1], as if they both originate from the same factory in China. Note. [1] https://encyclopedia.thefreedictionary.com/design+language Danke, -- Don, KB7RPU, https://www.qsl.net/kb7rpu There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.
Reply by ●June 19, 20222022-06-19
On Sunday, 19 June 2022 at 20:26:10 UTC+2, Don wrote:> Rich S wrote: > > Don wrote: > >> Many consumer grade USB power banks come with a built-in > >> automatic shutdown circuit. Light loads, such as the nominal > >> 6.8 μA drawn by a portable MP3 player, are not enough to > >> prevent shutdown. To compensate, this project uses > >> a 555 to nominally pull 100 mA every 5.5 seconds. > >> > >> ( excerpt - read more at https://crcomp.net/mp3mod/index.php ) > > > > Hello Don, you're obviously a handy guy, so > > why not just open up the power bank, and > > bypass that 'auto-shut-off' circuitry? > > > > Maybe you use this power back for other uses? > > So you still want the auto-shut off? > > > > I don't see the logic why that feature is needed > > in the power bank, anyway. Any electronic device (beyond > > a simple thing like a light) is likely to have its own auto-shut > > -off function. > > > > But you do want to preserve it, then I'd install a simple > > SPST switch to select bypassed- or native-behavior > > as you like. > One reason for me to leave the Power Bank unopened is it may open a can > of worms. Especially if it uses an undocumented, expoxied, exposed-lead > chip to control its charge cycle /and/ perform an automatic shutdown. > Also, my tear-down of the MP3 player to remove its battery and USB-B > port already sated my appetite to take things apart (for now). :) > You didn't comment on my MP3 player. Muchas Gracias. After all, the > player's merely an available adjunct to test my keepalive with a field > trial. > > Although the keepalive functioned as originally intended, the prospect > to double its efficiency tempted me to replace R2's original 150 K ohm > value with a 300 K ohm. So my page now reflects R2's new value: > <https://crcomp.net/mp3mod/index.php> > The keepalive successfully functions on two distinct Power Banks > with different capacities, marketed under separate brands. Besides auto- > shutdown, both Power Banks also share similar design language [1], as if > they both originate from the same factory in China. > > Note. > > [1] https://encyclopedia.thefreedictionary.com/design+language > Danke, > > -- > Don, KB7RPU, https://www.qsl.net/kb7rpu > There was a young lady named Bright Whose speed was far faster than light; > She set out one day In a relative way And returned on the previous night.https://crcomp.net/arpanet/index.php fake https://crcomp.net/beebivouac/index.php fake https://crcomp.net/pseudocell/index.php fake replace AA cell by Li-Ion battery + step down controller + solar cell https://crcomp.net/mp3mod/index.php fake
Reply by ●June 19, 20222022-06-19
Reply by ●June 19, 20222022-06-19
Reply by ●June 19, 20222022-06-19
On Sunday, 19 June 2022 at 21:02:08 UTC+2, John Doe wrote: .. John Doe’s profile photo John Doe 03:32 (19 hours ago) to Eddie, the Astraweb nym-shifting stalker is flagging off-topic posts with its forgery of my ID, then replies to its own forgery. Strange but true. Eddie has never posted anything NORMAL except when it got a spanking... https://groups.google.com/g/sci.electronics.repair/c/MesPLcGU4BE See also... John Doe <always.look message.header> (Astraweb, Aioe.org) Peter Weiner <dtgamer99 gmail.com> Edward H. <dtgamer99 gmail.com> Edward Hernandez <dtgamer99 gmail.com> -- John Doe <alway...@message.header> wrote:> Path: eternal-september.org!reader02.eternal-september.org!aioe.org!news.uzoreto.com!news-out.netnews.com!news.alt.net!fdc2.netnews.com!peer02.ams1!peer.ams1.xlned.com!news.xlned.com!peer03.ams4!peer.am4.highwinds-media.com!news.highwinds-media.com!fx03.ams4.POSTED!not-for-mail > From: John Doe <alway...@message.header> > Newsgroups: sci.electronics.design,free.spam > Subject: You have won an John Deere Mower > Followup-To: alt.test.group > References: <13751d9d-2179-4542...@googlegroups.com> > Injection-Date: Sat, 18 Jun 2022 19:02:40 -0000 (UTC) > Injection-Info: reader02.eternal-september.org; posting-host="aefae07b417003b570527823e77a9930"; logging-data="29200"; mail-complaints-to="ab...@eternal-september.org"; posting-account="U2FsdGVkX18QBXYPJWay5G0R7zD10mjY5gUD5xOvt6I=" > User-Agent: Xnews/2006.08.05 > Lines: 28 > Message-ID: <kQsrK.200683$BZ99...@usenetxs.com> > X-Complaints-To: https://www.astraweb.com/aup > NNTP-Posting-Date: Sat, 18 Jun 2022 23:02:40 UTC > Date: Sat, 18 Jun 2022 23:02:40 GMT > X-Received-Bytes: 2206 > Xref: reader02.eternal-september.org sci.electronics.design:671990 free.spam:19132
