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Re: SMD G1 transistor
Thanks Andy. How do you reply quoting parts of the message? Slick.?
yes Colorado is a model number of a Chev 4 door truck. Sorry I didn¡¯t consider that it could confuse. This is not a car group.?
The G1 is stamped on several components and a diode check with the meter I guessed they are NPN transistors. Somewhere in my searches 2N2222 came up and that seemed reasonable to me.? There is very little pad left on the G1 part for soldering. I probably should clean all solder off the board. Possibly parts of the pads are still there. I will do that. Vibration shouldn¡¯t be too severe. Would an intermittent short somewhere in the wires to the RR door melt the solder?? ?Seems a bit extreme to me. The two boards are similar but have obvious differences since original is 4door and the salvage is 2 door. The original part uses Qxx for transistors numbers. The salvage are identified with TRxx.?
If this board can¡¯t be repaired I will disconnect the wires to the motor and wire up an external reversing switch for the driver door using the same 12 volt DC supply. The RR door works fine from the passenger position just not from the driver control station. I can live with that inconvenience?
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Re: SMD G1 transistor
On Tue, Apr 29, 2025 at 02:57 PM, Pfaff1222 wrote:
I'm going to assume that is the year and model of a motor vehicle.? Not everyone speaks the same language, and "Colorado" doesn't make me think "car" nearly as much as "state", but I'm sure to you it's different.)
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Did the Google search include the kind of circuit board where it was used?? I am certainly no expert on in-house part numbers, but I would be cautious, if the "G1" was the only thing you were going from.
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G1 might mean anything, including a datecode, or a code for the manufacturer.? (But what do I know?!)
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That's pretty good information right there. Is it subject to much vibration?? Maybe consider a dab of glue or silicone to hold the transistor from shaking free.? Also, try adding thin wires soldered down to the traces leading to the pads, to get better contact with them, if you can access them. That's a tough choice.? Since the 2N2222 part seems very likely, I think I might go with that.? Unless it comes off again and you can't get another one in its place.? What can you lose? ?
Like I say, the code printed on the transistor might not mean anything important, but that is only a guess.? Can you tell if both boards have the same finished assembly part number?? I'm sure the service guys would go with choice #2.
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Andy
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How to control a latching impulse relay
I presently employ an X-10 Appliance Module and their 113A Mini Timer to control a 50AMP relay's 120VAC coil that switches power to our water heater.? Basically the water heater is only powered twice daily for fifteen minutes each. Of course, we can switch the circuit on from a variety of X-10 control devices should we need more hot water for any reason. I thought to look at latching relays thinking the ability to pulse the relay at each START time and again at each END time might prove move efficient sine we are not powering the relay coil save for the second or so it takes the PULSE to switch its state.? I found a video (o n YouTube) demonstrating how it might be controlled from several independent locations via momentary contact witches - "Impulse Relay (Latching Relay) Basic Function, Wiring and Application." So, assuming I can find a similar relay rated to switch the power to a water heater, I need a way to automate sending it a PULSE four times daily. I have mechanical timers that are able to turn the power on for several minutes - you know, the one's you plug a lamp into to give the impression you're at home when you're not -
but they are imprecise. I would prefer something digital if there is such a thing on the market. Any ideas? -- G.T. |
SMD G1 transistor
Need advice and thoughts from the experts. PCB on window control on 2005 Colorado. There are many SMD components. One came off. It has stamped on top G1 which from google searches is an NPN transistor similar to common 2N2222. There are several more. From schematics for the vehicle that transistor powers a relay which raises the RR window. I managed to resolder in place and the window operated fine several times but came off again later. I think the pads are damaged as one is very small (collector lead) so I¡¯m not surprised.?
Two things I¡¯ve considered doing: 1) solder a 2n2222 in its place.? 2) I found a similar control board at the salvage shop. The transistors have a different number though. BR02. What¡¯s the chances? |
Lenovo Adapter
Googol it - there's lots of options. You can get one from Amazon, test it out and may decided to return it and go with an AliBaba or Temu Buck Booster. I suspect that is what's in the 'brick' that lies between vehicle output an laptop input. Looks as if the proces are 'all over' the map. ? ? 14% OFF ? ? Lenovo 65W USB-C DC Adapter 40AK0065WW. 14% OFF. ? ? Lenovo 65W USB-C DC Adapter 40AK0065WW ? ? $59.95 ? ? Amazon.com - Seller & more ? ? ? ? Lenovo Open Source 65W DC Travel Adapter. ? ? Lenovo Open Source 65W DC Travel Adapter ? ? $29.00 ? ? Amazon & more ? ? Lenovo 65W USB-C AC Travel Adapter. ? ? Lenovo 65W USB-C AC Travel Adapter ? ? $79.99 ? ? Lenovo & more ? ? ? ? Lenovo 65W GaN Power Adapter. ? ? Lenovo 65W GaN Power Adapter ? ? $52.46 ? ? Amazon.com - Seller & more ? ? ? ? Lenovo 65W USB-C Wall Adapter. ? ? Lenovo 65W USB-C Wall Adapter ? ? $39.99 ? ? Lenovo & more ? ? 58% OFF ? ? Lenovo 65W AC Adapter. 58% OFF. ? ? Lenovo 65W AC Adapter ? ? $24.89 ? ? Amazon.com - Seller & more ? ? Lenovo Square Port 65W Power Adapter. 55% OFF. ? ? Lenovo Square Port 65W Power Adapter ? ? $2.95$7 ? ? Walmart - Seller & more ? ? 5.0(7) ? ? 65W Type-C USB C AC/DC Power Charger Adapter. ? ? 65W Type-C USB C AC/DC Power Charger Adapter ? ? $38.99 ? ? Amazon ? ? 65W Type-C USB C AC/DC Power Charger Adapter ? ? $38.99 ? ? Amazon -- G.T. |
Re: Boost Converter to run my laptop from my RV batteries.
¿ªÔÆÌåÓýAnd, replying to myself again, I should note that tinyurl further obfuscates the real target so it gets more difficult (if you don't speak native URLese) so ... just say no to bitly and tinyurl to save your neighbours. Real URLs are reasonably short and can be readily shared directly
if the tracking info is eliminated early in the process. Donald. On 4/20/25 18:04, dhlocker wrote:
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Re: Boost Converter to run my laptop from my RV batteries.
¿ªÔÆÌåÓýApologies for replying to myself - you can also (for both bitly and tinyurl) as a '+' after the tinyurl or bitly link to find out where it REALLY goes, then clip the "?....." stuff away from the link you find and see if it works. I don't like giving the internet lords the power to track my browsing habits and my friend connections. Donald. On 4/20/25 18:01, dhlocker wrote:
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Re: Boost Converter to run my laptop from my RV batteries.
¿ªÔÆÌåÓýFor those who are concerned about tinyurl and bitly security
(like I am) and internet tracking (like I am), the real target of
this link is For those who care, almost every link that includes a
"?blah=yadayadayada&somethingelse=morenonsensechars" you can
VERY SAFELY chop the "?everythingelse" and all following [tracking
data] and avoid getting tracked on the nets. It's easy to check
before you share a link - cut the "?blah=..." and see if the link
still works. It usually will - the extra stuff is just advertisers
tracking where you found their material, where else you visited,
and who your friends are! Donald. On 4/19/25 20:31, Dave via groups.io
wrote:
Maybe experiment with something like this from ebay. Read the description, looks like it may work for your use. Dave On 4/19/2025 4:08 PM, Luke Vogel via groups.io wrote:Hi all, I have a Lenovo laptop that currently uses an AC power supply (135W).? I think the output is aprox 20V. I'd like to be able to run it from the RV batteries (typically 12 to 13V) without the need for an inverter. I think the major issue is the current draw.? 135W at 20V can draw 6.75A so a 12V boost converter would probably draw 11.25+ Amps. Any thoughts on how best to achieve this? Luke |
Re: Boost Converter to run my laptop from my RV batteries.
Hi TJTomPhillips,
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No, this wont work as it cannot deliver the current needed.
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Hi Andy,
a DC-DC boost converter is not an inverter.? I was hoping to avoid the use of the inverter I already have because there is additional overhead on that device that will draw more current from my RV batteries.? I'm aiming for a reasonably efficient solution.
Hi Dave, Yes, this looks like it may do the job.? The description of the product recommends additional cooling if the current draw exceeds 8A.? This may not be a problem though because I believe full current draw would only be necessary if charging an almost flat battery.? As the battery state of charge improves the bulk charge current would reduce. ?
I'll investigate this option further.?
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Thank-you all for your replies.
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Luke
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Re: Boost Converter to run my laptop from my RV batteries.
On Saturday 19 April 2025 07:42:44 pm Andy via groups.io wrote:
Are we at odds over use of the word "inverter"?? You spoke of a "boost converter", but isn't that an inverter?No. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
Re: Boost Converter to run my laptop from my RV batteries.
An excellent solution is to buy a Lenovo 65W USB-C DC Travel Adapter. See . With that unit, you would have one that you can trust to safely power your laptop and save the time an expense to experiment with building your own device.
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You can also find third party adapters at cheaper prices but then you would need to evaluate user reviews for the one you buy. |
Re: Boost Converter to run my laptop from my RV batteries.
Maybe experiment with something like this from ebay. Read the description, looks like it may work for your use.
toggle quoted message
Show quoted text
Dave On 4/19/2025 4:08 PM, Luke Vogel via groups.io wrote:
Hi all, |
Re: Boost Converter to run my laptop from my RV batteries.
Perhaps you were thinking of an "inverter" as something to generate a 60 Hz, 120 V sinewave.? That is one kind of inverter.
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But a boost converter to go from 12 V to 20 V is also an inverter.
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I may have misunderstood you when you wrote "without the need for an inverter".
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Andy
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Re: Boost Converter to run my laptop from my RV batteries.
On Sat, Apr 19, 2025 at 07:20 PM, Luke Vogel wrote:
So, the question you need to answer is:? Can you correctly power the circuits inside the laptop that normally need 20 V, from just a 12 - 13 V power source and no inverter? ?
My first answer is "no!"? Not without an inverter to boost it up to 20 V.? But to correctly answer it, you would need to know exactly what inside the laptop gets driven by that DC input voltage, and whether or not it can accommodate such a low voltage.? If it goes directly into an internal DC-DC converter (and nothing else) and if that converter is compliant enough to accept 12 V without a hiccup, then OK.? But do you have access to the schematic and internal parts list for this laptop?
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Without that, I think the best you can say is that it is highly unlikely to work without an inverter.
I think that is incorrect.? Electronic circuits need certain voltages to work properly, and if 12 V is too little compared to the 20 V that it needs, then either it won't work with only 12 V, or it could let out the "magic smoke", or do something else bad.
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Yes, that is a reasonable estimate - if you can use a high efficiency inverter. ?
Note that your RV's battery might be as much as 15 V when charging.
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Also make sure that the laptop actually needs 20 V.? How did you determine that?? If you measured its AC-DC power supply without the laptop connected, it might not be the normal in-circuit voltage, as you probably know.
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Are we at odds over use of the word "inverter"?? You spoke of a "boost converter", but isn't that an inverter?
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Andy
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Boost Converter to run my laptop from my RV batteries.
Hi all,
I have a Lenovo laptop that currently uses an AC power supply (135W).? I think the output is aprox 20V.
?
I'd like to be able to run it from the RV batteries (typically 12 to 13V) without the need for an inverter.
?
I think the major issue is the current draw.? 135W at 20V can draw 6.75A so a 12V boost converter would probably draw 11.25+ Amps.
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Any thoughts on how best to achieve this?
?
Luke
?
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Re: controlling mosfet biasing directly in the circuit question
FYI, the minimum recommended Length and Width for your "NMOS" N-channel MOSFETs are:
? L=10000n
? W=10000n
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Using your dimensions results in warnings from LTspice.
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It is possible that LTspice quietly changes the Length and Width to these recommended minimum values.? Or it might use the values you asked for,, even if they result in miscalculations in the model formulas.? The model was not designed to be used with such small dimensions as yours.? They were impossible dimensions in 1975.
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Andy
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Re: controlling mosfet biasing directly in the circuit question
On Sat, Apr 12, 2025 at 09:53 AM, john23 wrote:
First, you have made some mistakes, which you should fix before progressing further. ?
The P-channel MOSFETs are correctly named so that they use your CMOSP (BSIM3) model.? However, all of your N-channel MOSFETs are still named "NMOS", so all of them are LEVEL=1 MOSFETs using 1975 technology, and are certainly incorrect for 180nm MOSFETs.? You can not expect that simulation to have meaningful results.? They do not use the P-channel .MODEL on your schematic because the model names are incorrect.
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In order to use the T588F SPICE BSIM models, you need to name your MOSFETs to agree with the .MODELs.
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It is unlikely (but not impossible) that both N-channel and P-channel MOSFETs would ave the same dimensions.? Often the P-channel MOSFETs need to be wider, in part because of the differences between N and P materials.
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It is possible (uncertain) that you have the wrong LEVEL number in these two .MODEL statements.? At the top, it states, that the LEVEL should be 8 for SPICE 3F5, and 49 for HSPICE.? LTspice has capability of both LEVEL=8 and LEVEL=49, and it is unclear which one you should use.? LEVEL=8 is described in the Help as:
SPICE 3F5 is from U-Cal Berkeley.? LEVEL=49 is not described in the Help, but it does work in LTspice (probably added for compatibility with HSPICE's LEVEL=49 models).? I am not sure but I think HSPICE chose to make their LEVEL=8 differ from the "standard" (Berkeley) LEVEL=8 model, and so they had to fix that problem by making a brand new LEVEL=49.? There is the possibility that LEVEL=8 and LEVEL=49 are either the same or so close (in LTspice) to be indistinguishable from one another, but that is only an uneducated guess.? HSPICE describes their LEVEL=8 as "advanced LEVEL 2", and LTspice clearly states that it is BSIM3, which is what these models are.? (Unfortunately, there is no central clearinghouse for SPICE MOSFET LEVEL numbers.? That creates problems, like this one, where it is unclear which model should be used.) What are M3,5,1,2 and M4,6?? I cannot find them on your schematic. ?
Are you trying to adjust the dimensions of the MOSFETs?? Or adjust the voltage sources?? Or adjust the resistance value of R1?? Or all three?
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Can you pull out individual MOSFETs from the circuit, and sweep them (.DC sweeps) to see their characteristics, then use that information to set up your circuit's biasing the way you want it to be?
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Andy
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Re: converting mathematical into plot like extraction of W/L params
On Fri, Apr 18, 2025 at 06:50 AM, john23 wrote:
What and where is "step 3"? ?
If you know that "step 3" uses approximations and that there is a better way, why not tell us what is this better way? ?
Andy
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converting mathematical into plot like extraction of W/L params
Hello , I am trying to follow the example shown in the manual below. In step 3 they find the proper W/L using mathematical expressions. However I know that these formulas are aproximations ,the realistic way is to usr characteristic plots. What caractestics plots you reccomend me to use in order to get the proper W/L? Thanks. |
Re: Off topic on PC Popups
¿ªÔÆÌåÓýDan,
There are many videos that shows how to install win11 on unsupported hardware :
There are some hard requirements (4 gb ram minimum, must be able to run 64 bit os, etc.). ? So not all old hardware is physically able to run win11, but at the same time not all unsupported hardware is unable to either.
Some of those videos tells you want to check before trying to install win11 on old hardware.
Jong?
On Apr 17, 2025, at 2:55 AM, Dan Kahn via groups.io <dankahn88@...> wrote:
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