This ought to work and has some real virtues. https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 -- Anybody can count to one. - Robert Widlar
power supply 1-wire remote sense
Started by ●June 17, 2022
Reply by ●June 17, 20222022-06-17
On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote:> This ought to work and has some real virtues. > > https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >That looks just like a three-wire resistance thermometer connection. John
Reply by ●June 17, 20222022-06-17
On Friday, June 17, 2022 at 12:40:06 PM UTC-7, John Walliker wrote:> On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: > > This ought to work and has some real virtues. > > > > https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 > > > That looks just like a three-wire resistance thermometer connection.Yep, and the downside is, any contact resistance in connectors or mismatch in current-delivery wire resistance does it in. Point-of-load regulation is cheaper (wire has real cost) and has better latency and bandwidth than digitizing-at-the-source. Is this a motor control, or heater, or some other milliseconds-don't-matter system?
Reply by ●June 17, 20222022-06-17
On Fri, 17 Jun 2022 12:39:59 -0700 (PDT), John Walliker <jrwalliker@gmail.com> wrote:>On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: >> This ought to work and has some real virtues. >> >> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >> > >That looks just like a three-wire resistance thermometer connection. > >JohnSimilar concept, an assumption of equal wire resistances. -- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in certainties. Francis Bacon
Reply by ●June 17, 20222022-06-17
On Fri, 17 Jun 2022 13:01:28 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote:>On Friday, June 17, 2022 at 12:40:06 PM UTC-7, John Walliker wrote: >> On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: >> > This ought to work and has some real virtues. >> > >> > https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >> > >> That looks just like a three-wire resistance thermometer connection. > >Yep, and the downside is, any contact resistance in connectors or mismatch in current-delivery >wire resistance does it in. Point-of-load regulation is cheaper (wire has real cost) and >has better latency and bandwidth than digitizing-at-the-source. Is this a motor control, >or heater, or some other milliseconds-don't-matter system?It's a programmable DC power supply, and the customer has requested remote sense. Here's the opposite extreme of remote sense: https://www.dropbox.com/s/d3zd779cob33zyg/P941_Rem_Sense_4.jpg?raw=1 That has some nice features. -- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in certainties. Francis Bacon
Reply by ●June 17, 20222022-06-17
On 2022/06/17 2:39 p.m., John Larkin wrote:> On Fri, 17 Jun 2022 13:01:28 -0700 (PDT), whit3rd <whit3rd@gmail.com> > wrote: > >> On Friday, June 17, 2022 at 12:40:06 PM UTC-7, John Walliker wrote: >>> On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: >>>> This ought to work and has some real virtues. >>>> >>>> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >>>> >>> That looks just like a three-wire resistance thermometer connection. >> >> Yep, and the downside is, any contact resistance in connectors or mismatch in current-delivery >> wire resistance does it in. Point-of-load regulation is cheaper (wire has real cost) and >> has better latency and bandwidth than digitizing-at-the-source. Is this a motor control, >> or heater, or some other milliseconds-don't-matter system? > > It's a programmable DC power supply, and the customer has requested > remote sense. > > Here's the opposite extreme of remote sense: > > https://www.dropbox.com/s/d3zd779cob33zyg/P941_Rem_Sense_4.jpg?raw=1 > > That has some nice features. > >I remember the early 80s when Atari used to use sense lines to monitor the power supply output at the game board. Many smoked card edge connectors later they gave up on the sense lines. What was happening was the ground connections to the game boards deteriorated at the same rate as the +DC ones and this confused the sense(s) so they would allow more current to flow - and toasted the card edge connectors and the plugs. We had a lot of problems with ground/common connections on games designed in the 70s and 80s. I assume your design allows for this - I was just doing some reminiscing... John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."
Reply by ●June 17, 20222022-06-17
On Fri, 17 Jun 2022 15:05:08 -0700, John Robertson <spam@flippers.com> wrote:>On 2022/06/17 2:39 p.m., John Larkin wrote: >> On Fri, 17 Jun 2022 13:01:28 -0700 (PDT), whit3rd <whit3rd@gmail.com> >> wrote: >> >>> On Friday, June 17, 2022 at 12:40:06 PM UTC-7, John Walliker wrote: >>>> On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: >>>>> This ought to work and has some real virtues. >>>>> >>>>> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >>>>> >>>> That looks just like a three-wire resistance thermometer connection. >>> >>> Yep, and the downside is, any contact resistance in connectors or mismatch in current-delivery >>> wire resistance does it in. Point-of-load regulation is cheaper (wire has real cost) and >>> has better latency and bandwidth than digitizing-at-the-source. Is this a motor control, >>> or heater, or some other milliseconds-don't-matter system? >> >> It's a programmable DC power supply, and the customer has requested >> remote sense. >> >> Here's the opposite extreme of remote sense: >> >> https://www.dropbox.com/s/d3zd779cob33zyg/P941_Rem_Sense_4.jpg?raw=1 >> >> That has some nice features. >> >> > >I remember the early 80s when Atari used to use sense lines to monitor >the power supply output at the game board. > >Many smoked card edge connectors later they gave up on the sense lines. >What was happening was the ground connections to the game boards >deteriorated at the same rate as the +DC ones and this confused the >sense(s) so they would allow more current to flow - and toasted the card >edge connectors and the plugs. > >We had a lot of problems with ground/common connections on games >designed in the 70s and 80s. > >I assume your design allows for this - I was just doing some reminiscing... > >John :-#)#Yes, rs can be connected wrong and make a power supply go nuts. The dual ADC allows us to compare the output and the rs feedback and see if they make sense. -- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in certainties. Francis Bacon
Reply by ●June 18, 20222022-06-18
On Friday, June 17, 2022 at 3:24:13 PM UTC-7, John Larkin wrote:> On Fri, 17 Jun 2022 15:05:08 -0700, John Robertson <sp...@flippers.com> > wrote: > >On 2022/06/17 2:39 p.m., John Larkin wrote: > >> On Fri, 17 Jun 2022 13:01:28 -0700 (PDT), whit3rd <whi...@gmail.com> > >> wrote: > >> > >>> On Friday, June 17, 2022 at 12:40:06 PM UTC-7, John Walliker wrote: > >>>> On Friday, 17 June 2022 at 17:45:41 UTC+1, jla...@highlandsniptechnology.com wrote: > >>>>> This ought to work and has some real virtues. > >>>>> > >>>>> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 > >>>>> > >>>> That looks just like a three-wire resistance thermometer connection. > >>> > >>> Yep, and the downside is, any contact resistance in connectors or mismatch in current-delivery > >>> wire resistance does it in. Point-of-load regulation is cheaper (wire has real cost) and > >>> has better latency and bandwidth than digitizing-at-the-source. Is this a motor control, > >>> or heater, or some other milliseconds-don't-matter system? > >> > >> It's a programmable DC power supply, and the customer has requested > >> remote sense.> >What was happening was the ground connections to the game boards > >deteriorated at the same rate as the +DC ones and this confused the > >sense(s) so they would allow more current to flow - and toasted the card > >edge connectors and the plugs. > > > >We had a lot of problems with ground/common connections on games > >designed in the 70s and 80s.> Yes, rs can be connected wrong and make a power supply go nuts. The > dual ADC allows us to compare the output and the rs feedback and see > if they make sense.I'd prefer fewer ADCs (thinking of these as feedback elements into an op amp-style regulator) because of their delays. Ideally, just program a reference, and apply gain to that, with suitable filter caps on the output. MHz power currents come from the capacitors, kHz power currents come from the amplifier, and a single ADC can alternate reading the reference and the output; using three ADCs seems overcomplex. If you just integrate DC errors (P-I-D style) using the digital stuff, the delay isn't an issue. As for 'make sense' decisions: overcurrent or overvoltage would usually not wait for a smart digital chip's decision, but do something appropriate with a protective relay, circuit breaker, fuse... Undervoltage though, that's where a sense wire solution shines (take a millisecond, but get the value RIGHT before a guy with a meter sees the problem).
Reply by ●June 18, 20222022-06-18
John Robertson <spam@flippers.com> wrote:> John Larkin wrote: >> whit3rd wrote: >>> John Walliker wrote: >>>> jla...@highlandsniptechnology.com wrote:>>>>> This ought to work and has some real virtues. >>>>> >>>>> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 >>>>> >>>> That looks just like a three-wire resistance thermometer connection. >>> >>> Yep, and the downside is, any contact resistance in connectors or >>> mismatch in current-delivery wire resistance does it in. >>> Point-of-load regulation is cheaper (wire has real cost) and has >>> better latency and bandwidth than digitizing-at-the-source. Is this >>> a motor control, or heater, or some other milliseconds-don't-matter >>> system? >> >> It's a programmable DC power supply, and the customer has requested >> remote sense. >> >> Here's the opposite extreme of remote sense: >> >> https://www.dropbox.com/s/d3zd779cob33zyg/P941_Rem_Sense_4.jpg?raw=1 >> >> That has some nice features. > > I remember the early 80s when Atari used to use sense lines to monitor > the power supply output at the game board. > > Many smoked card edge connectors later they gave up on the sense lines. > What was happening was the ground connections to the game boards > deteriorated at the same rate as the +DC ones and this confused the > sense(s) so they would allow more current to flow - and toasted the card > edge connectors and the plugs. > > We had a lot of problems with ground/common connections on games > designed in the 70s and 80s. > > I assume your design allows for this - I was just doing some > reminiscing...Not electronics... As a kid, I was gifted $60 and spent most of it on pinball. Maybe a nickel per game. As an adult, played pinball after work, my favorite being Firepower when quick action flippers came along. Then noticed video games on the other side of the arcade... After sinking maybe $50 into Asteroids, played it for hours on one quarter. Then Missile Command. Coincidently, met an electronics engineer (I had played once in a high school chess tournament) who recommended separating the fire between the left and the right screen, left button half way then right button the other half way. Then could play Missile Command for an hour or two on one quarter. Little after that.
Reply by ●June 18, 20222022-06-18
Off topic troll... -- John Doe <always.look@message.header> wrote:> Path: not-for-mail > From: John Doe <always.look@message.header> > Newsgroups: sci.electronics.design > Subject: Re: power supply 1-wire remote sense > Date: Sat, 18 Jun 2022 08:37:35 -0000 (UTC) > Organization: A noiseless patient Spider > Lines: 56 > Message-ID: <t8k2sf$nna$1@dont-email.me> > References: <jqbpahdaj72a4ar3sfban3hgmulttrbfi3@4ax.com> <a8f77647-1b36-4621-87df-264512a2cc27n@googlegroups.com> <fee7c65c-1e2e-4a44-b7be-2f06c609715bn@googlegroups.com> <53ppah1es0nl6tsgblhnjs8f96jvadcgbt@4ax.com> <P7qdnSQX-_EIZzH_nZ2dnUU7-ffNnZ2d@giganews.com> > Injection-Date: Sat, 18 Jun 2022 08:37:35 -0000 (UTC) > Injection-Info: reader02.eternal-september.org; posting-host="6f6224e8e964955c3a1215fa70e2816d"; > logging-data="24298"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+T4MAr2D6ilLYIcbqQtkJyfb2QEApktSA=" > User-Agent: Xnews/2006.08.05 > Cancel-Lock: sha1:r7KGig83sueiMQRqx0EM/rEa9N4= > X-Received-Bytes: 3408 > > John Robertson <spam@flippers.com> wrote: > > > John Larkin wrote: > >> whit3rd wrote: > >>> John Walliker wrote: > >>>> jla...@highlandsniptechnology.com wrote: > > >>>>> This ought to work and has some real virtues. > >>>>> > >>>>> https://www.dropbox.com/s/s3swzhh7b0kd8f9/1-wire_sense.jpg?raw=1 > >>>>> > >>>> That looks just like a three-wire resistance thermometer connection. > >>> > >>> Yep, and the downside is, any contact resistance in connectors or > >>> mismatch in current-delivery wire resistance does it in. > >>> Point-of-load regulation is cheaper (wire has real cost) and has > >>> better latency and bandwidth than digitizing-at-the-source. Is this > >>> a motor control, or heater, or some other milliseconds-don't-matter > >>> system? > >> > >> It's a programmable DC power supply, and the customer has requested > >> remote sense. > >> > >> Here's the opposite extreme of remote sense: > >> > >> https://www.dropbox.com/s/d3zd779cob33zyg/P941_Rem_Sense_4.jpg?raw=1 > >> > >> That has some nice features. > > > > I remember the early 80s when Atari used to use sense lines to monitor > > the power supply output at the game board. > > > > Many smoked card edge connectors later they gave up on the sense lines. > > What was happening was the ground connections to the game boards > > deteriorated at the same rate as the +DC ones and this confused the > > sense(s) so they would allow more current to flow - and toasted the card > > edge connectors and the plugs. > > > > We had a lot of problems with ground/common connections on games > > designed in the 70s and 80s. > > > > I assume your design allows for this - I was just doing some > > reminiscing... > > Not electronics... > > As a kid, I was gifted $60 and spent most of it on pinball. Maybe a nickel > per game. As an adult, played pinball after work, my favorite being > Firepower when quick action flippers came along. Then noticed video games > on the other side of the arcade... After sinking maybe $50 into Asteroids, > played it for hours on one quarter. Then Missile Command. Coincidently, > met an electronics engineer (I had played once in a high school chess > tournament) who recommended separating the fire between the left and the > right screen, left button half way then right button the other half way. > Then could play Missile Command for an hour or two on one quarter. Little > after that.
