hybridfree/eevblog-posts huggingface dataset:
Laptop battery repair Asus x550 - Page 1
Forum section: electronics / beginners

author: ABHIRAMSHIBU
author_rank: Contributor
timestamp: March 31, 2017, 01:58:54 am
content: My battery just started to die on my laptop. So I thought of replacing it. Since I got the battery replaced now, I can try to repair the old battery pack.I bust open the battery. With a screw driver and a hammer ( it was sealed pretty tight ). I made sure that I don't go too far into the battery and also made sure that I don't poke or puncture liion cells as they might start smoking..Now I measured the battery voltage. This battery is half charged. I didn't discharge it completely just because it will take some time for me to repair it and I don't want all cells to die. I can use these cells as a power bank or a sort of power supply for by micro controller projects.Battery voltages (4cells). LGABD11865Cell 1-4.06VCell 2-4.12VCell 3-3.98VCell 4-4.11VAs I know laptop batteries have balanced charging and discharging ( is I can't find out which cell is faulty just via voltage ). I don't know the pinouts of the the header. But what I can provide is there is a ti battery gauge (BQ30Z53) rest of the Ic didn't make much sense.And I can confirm that the battery works now also.. I havint tried replacing cells.. But tried to put in laptop. I get 30 min backup now also.So my question.I can only find different cells which are 18650 instead of 1865 here in India. Most if cells are 2600mAh but original cell is 3000. I found a cell which has 3000 but idk if its fake or real.Link-https://www.amazon.in/dp/B00RV38MCM/ref=cm_sw_r_cp_apa_i_wyB3ybVKDCM5CNow how do I connect these. These are connected via very high surface area metal strips which idk where to get them.Some claim that when the battery itself is removed from circuitry all info about battery are lost and the circuit is useless.. Please tell me how to do like without losing data.Please guide me...Thanks in advance!

author: Audioguru
author_rank: Super Contributor
timestamp: March 31, 2017, 02:03:46 am
content: Many Ultra-Fire Li-Ion cells sold on ebay are fakes:

author: ABHIRAMSHIBU
author_rank: Contributor
timestamp: March 31, 2017, 02:05:47 am
content: Yeah I also thought so. So if I use a 2600mah lg cell, will the battery charge normally?Btw its amazon. But there are now so many custom sellers...

author: amyk
author_rank: Super Contributor
timestamp: March 31, 2017, 11:44:37 am
content: Cell 3 is the bad one, but you should replace all 4.These are actually4.35Vcells, so you must replace with the same type. Standard 4.2V cells will either die very quickly or "vent with flame" from being overcharged. The model number is ICR18650D1 and you can easily find sellers online.http://lygte-info.dk/review/batteries2012/LG%2018650%20D1%203000mAh%20(Pink)%20UK.htmlhttp://keeppower.com.ua/download/2015-01/datasheet_LG-ICR18650D1.pdf

author: Neo2199
author_rank: Contributor
timestamp: April 02, 2017, 04:04:53 pm
content: If You are going to replace the batteries then You should find data sheet from battery gauge used in the pack. There is typically an order in which batteries are connected. I couldn't find one for Your chip.
Laptop Bias Lighting with ESP8266 and SK6812 – Powering Options? - Page 1
Forum section: electronics / beginners

author: nox
author_rank: Newbie
timestamp: October 05, 2025, 01:15:16 am
content: Hey everyone,I’m a college student / hobbyist who enjoys tinkering with interesting stuff.I’m currently planning to add bias lighting behind my laptop screen using a strip of BTF SK6812 (addressable RGBNW) LEDs and an ESP8266 to drive them. The LEDs will be attached to the back of the laptop display lid, with color and brightness dynamically controlled (possibly synced to f.lux).My main concern right now is how to power the LED strip safely and reliably.Setup:• Controller: NodeMCU ESP8266• LEDs: SK6812 RGBNW (5V version, from BTF Lighting, 60LED/m)• Goal: Subtle bias lighting, not full brightness• Mounting: Directly behind laptop screen lid, powered from same laptop setup (no external wall adapter ideally)Potential Power Solutions:a. From the Laptop Charger (internal tap):My laptop’s adapter is rated at 19.5V / 9.23A (180W).I was considering opening the laptop and finding the DC input line, then using a buck converter to get a stable 5V rail for the SK6812 and ESP8266.→ Concern: Ground loops, interference, and potential risk to the laptop’s mainboard.b. From USB-C PD Power Source:Use a PD trigger board with a 22.5W or 30W charger/powerbank to negotiate a 5V / 3A output, and power both the ESP8266 and LEDs externally.→ Safer, but might be less “integrated” into the laptop setup.I measured that the length of strip I'll be needing is only 71cm, for a 60LED/m strip, that's about 43 LEDs (if my math is right).Which of these two methods would you consider safer and more electrically sound?Cheers!
Laptop charger confusion! - Page 1
Forum section: electronics / beginners

author: DeBeng
author_rank: Newbie
timestamp: August 12, 2014, 02:10:56 pm
content: I am a little confused by this laptop charger.It says 240 at 1.2 amps. That works out to be 290watts. I am just a bit confused by how a laptop charger like that consumes 290watts of power and outputs 65 watts of power?Am I doing something wrong working out the power input? I am using the equation P=VI.I have never really done anything with ac power so I don't quite know how ac power works.(Sorry if you don't understand what I am trying to say, I am horrible at explaining things!)Thanks!

author: Simon
author_rank: Unknown
timestamp: August 12, 2014, 02:12:17 pm
content: It could be what the input is fused for or what you should allow for peak draw say if your putting a fuse in front of it. It does not necessarily mean that it uses that amount non stop.

author: DeBeng
author_rank: Newbie
timestamp: August 12, 2014, 02:18:01 pm
content: Ok. But I am still confused about the efficiency. 290watts input and 65 watts output at peak works out to be 23% efficiency. Is that normal for chargers? Or am I doing something completely wrong?

author: Simon
author_rank: Unknown
timestamp: August 12, 2014, 02:20:04 pm
content: That is the fuse rating not the power consumption, you never rate a fuse for the actual power consumption or it blows the fuse. the unit does not use 290W but will allow a peak power draw of that amount for a fraction of a second before blowing the fuse or tripping any other protection device..

author: DeBeng
author_rank: Newbie
timestamp: August 12, 2014, 02:24:06 pm
content: Ok. Thanks for the help!
laptop charger problem - Page 1
Forum section: electronics / beginners

author: kafor1
author_rank: Contributor
timestamp: October 21, 2019, 07:16:05 am
content: hey guys so i have a problem.before i was using a 19v 3.42A charger for my laptop, and now it broke. i checked inside and it doesnt produce output anymore and theres no part sold here.so i was planning to buy a 19v 4.5A universal charger, since i can't buy a charger similar rating. and i tried it, it works. but i didnt buy it. thats why im here to ask that question. is it ok for me to buy that laptop with different A specs?

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 21, 2019, 07:24:11 am
content: A charger that can deliver more current should not be a problem, the laptop takes what is needed.

author: kafor1
author_rank: Contributor
timestamp: October 21, 2019, 07:30:17 am
content: Quote from: PA0PBZ on October 21, 2019, 07:24:11 amso there is no risk of my laptop exploding or something?

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 21, 2019, 07:50:30 am
content: Quote from: kafor1 on October 21, 2019, 07:30:17 amNot because of using this replacement charger.

author: kafor1
author_rank: Contributor
timestamp: October 21, 2019, 07:53:35 am
content: Quote from: PA0PBZ on October 21, 2019, 07:50:30 amThanks!
Laptop charging - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: March 17, 2017, 05:44:32 pm
content: If I plug in a charger, what voltage should I measure coming to battery from charger?100% of the output voltage of the charger?Or less?Is voltage from the charger coming through any charger controller on mainboard?If I follow this procedure:I Remove batteryConnect a chargerMeasure voltage on the connector and there is voltage( for a short time),so the path charger --> battery is OKConnect the batteryYet, no charging even though there is a voltage on the battery connector( but not sure if it is coming from the battery or from the charger)Does it mean the charging controller is faulty? or software problem?ANd what is a function of the charging controller on the mainboard?Thank you for explanation

author: 5321488
author_rank: Contributor
timestamp: March 18, 2017, 12:51:37 am
content: At the output connector of the charger, you should measure very similar to the specified output voltage.Unless you have modified software for the charging controller, which I can imagine would be difficult, it is probably a hardware fault. The controller will interface the processor, battery and power input to stop charging when full, to prevent overload or overcharge, maybe have a low voltage disconnect - stop discharge when batteries get too low.Maybe start by visually inspecting the controller, which should be close to the input connector, for any burnt or bulging components?

author: Audioguru
author_rank: Super Contributor
timestamp: March 18, 2017, 01:01:04 am
content: On the other website I said that the "charger" is not a battery charger, instead it is a power supply for the charger circuit inside the laptop. If you connect the power supply to the battery then the battery might blow up unless it has a protection circuit to prevent what you are foolishly trying to do.You do not even know which connector pins on the battery are +, - or the temperature sensor.A Lithium battery lasts for about 2 years. When it is worn out then it should be replaced by a good one, not a cheap fake one from ebay.The charger circuit limits the current and voltage. When it detects a full charge then disconnects the battery from the charger.

author: Nusa
author_rank: Super Contributor
timestamp: March 18, 2017, 01:11:03 am
content: What laptop model?What battery chemistry?What voltage did you measure without the battery pack?What's the labeled battery pack voltage?What's the measured battery pack voltage?What % charge does the system report for the battery pack? Will the system run on battery-only?

author: 5321488
author_rank: Contributor
timestamp: March 18, 2017, 01:30:52 am
content: Quote from: 5321488 on March 18, 2017, 12:51:37 amDisregard that - I didn't properly read what you were trying to do.Definitely don't do that, listen to the advice above!
laptop keyboard intereference  - Page 1
Forum section: electronics / beginners

author: nickeevblog10
author_rank: Contributor
timestamp: February 09, 2018, 02:08:40 am
content: ...I am not sure which Forum Section I should post this...Seemingly a common problem to laptop keyboards and not always solved by replacing the keyboard but by covering the laptop keyboard ribbon with tin foil.I have someone else laptop here with this problem. Sometimes it will work most times it will not work. Sometimes some keys work and sometimes they do not work. Every time insulate between the keyboard and the motherboard with layers of paper there is a change in the keyboard behavior some of the keys beginning to work properly again.Clearly a motherboard manufacturing flaw but what could be causing the problem.Perhaps even the extra pressure going onto the motherboard by the extra thickness of paper is showing there could be a damaged solder point.This laptop model is Asus X55C and I am wondering what other measures I can take to test for perhaps a motherboard issuing electromagnetism (< a wild guess on my part).I also tried shielding between the motherboard and the keyboard with a thick plastic to no effect.I guess one question to ask the experts is, what kind of emissions are there from laptop motherboards? There is magnetism from speakers and there will be wireless emission or wireless transmission or something like that and any other kinds of energy from powered devices.
Laptop LCD Display dimming - Page 1
Forum section: electronics / beginners

author: Michelemmike
author_rank: Newbie
timestamp: April 24, 2022, 04:00:38 pm
content: Hi,I want to upgrade my current laptop display which is a PANDA LM156LFCL07 which uses PWM with a better one (an Innolux N156HCG-EN1) . The specs sheet says both "LED DC Dimming" and "PWM frequency (190-2K)Hz", so I'm confused.Here is the link to the comparison with my display:https://www.panelook.com/modelcompare.php?ids=46058,45792So I'm wondering if Innolux is saying that the screen uses both DC dimming AND PWM or if the control is entirely determined by the laptop's motherboard. So, if it's controlled by the motherboard, I think installing a display that supports DC dimming will not mean that it will actually work with DC dimming, if the motherboard doesn't want it to.What do you think? Who controls PWM?Thank you in advanceMichele

author: amyk
author_rank: Super Contributor
timestamp: April 25, 2022, 12:30:21 am
content: Do they even have the same pinout?

author: Michelemmike
author_rank: Newbie
timestamp: April 25, 2022, 07:18:23 am
content: Yes, both use eDP 1.2
laptop lcd  - Page 1
Forum section: electronics / beginners

author: hpibmx
author_rank: Regular Contributor
timestamp: July 18, 2021, 06:14:05 pm
content: Hi,my laptop dell E5440 got small water damage and the A/C on top of my table and after a day leaving it and trying with blower,sometimes (most of time) works fine, but when I'm trying to wake it from sleep or restarting, screen goes black with some lines the comes back tom normal after about 2 to 3 minutes.So would this be lcd issue or backlight circuit?I don't have any extra lcd to try it out.. has anyone experienced this before?I really appreciate your help.Thank you.

author: fordem
author_rank: Regular Contributor
timestamp: July 19, 2021, 12:20:51 am
content: Definitely NOT a backlight issue - either LCD or cable and my guess would be the LCD - BUT - having said that I would start by reseating the cable, nothing to lose but your time.

author: hpibmx
author_rank: Regular Contributor
timestamp: July 19, 2021, 05:10:20 am
content: Yes, that's what i thought and reseated it, just unplugged and plugged back in, no changes.thanks for suggestion

author: jenniferkim
author_rank: Contributor
timestamp: July 19, 2021, 05:30:44 am
content: looks like an LCD issue, give it one more day.Once I dropped my phone in water and after like 3 4 hours, it started working fine but its LCD had small water droplets on the inside. I once dropped aPCB Panelas well.

author: perieanuo
author_rank: Frequent Contributor
timestamp: July 19, 2021, 11:59:33 am
content: hi,most likely between the 'video card' and LCD you have either oxidised connector/flat cable, either 'short'where you had the water damage, clean and try some contact sprayinspect your mobo pcb, otherwise, if you miss water there, later it will be to late to eliminate corrosion/short between signal paths/gnd/vcc
Laptop power supplies - Page 1
Forum section: electronics / beginners

author: MichaelW
author_rank: Contributor
timestamp: October 14, 2013, 10:37:07 pm
content: I have a bunch of laptop power supplies that I've saved for a few years and since I started working on an EE degree I've been wanting to work on some cool electronics projects, and I'm sure at some point I'd have to provide power to something that I'd rather not have to buy batteries for. So, I thought I'd research reusing those power supplies as a possibility.For instance, say I have a laptop brick that supplies 12v and 3 amps. My current understanding is that it would provide whatever amperage the load pulls UP to 3 amps. So if I had a 12v circuit that needed 1 amp, that power supply would provide 1 amp, and not try to put 3 amps into the circuit, right?Thanks for any help. :-)

author: Jon Chandler
author_rank: Frequent Contributor
timestamp: October 14, 2013, 10:49:01 pm
content: Exactly correct. The circuit only draws the current it needs.

author: Zbig
author_rank: Frequent Contributor
timestamp: October 14, 2013, 10:52:40 pm
content: Yup, you understand it correctly - the current figure on your PSU states its capability to deliver up to this maximum current. It's a very common beginners' misconception that the voltage and current are two disparate and nonrelated things and you can adjust both of them independently given a constant load. Obviously that's not true and subject to the Ohm's law. Assuming that any load could be substituted with a resistance (very rough simplification but good enough for DC current calculations), I=U/R and you see there's no way to blow your laptop using a power brick with "too many Amps" (and that's exactly what many people seem to think).

author: MichaelW
author_rank: Contributor
timestamp: October 15, 2013, 01:31:52 am
content: Thanks for the confirmation guys!I actually had a mini-argument (friendly) with a classmate of mine about this, he was convinced that I'd get the entire 3 amps into whatever I connected it to and I tried to use the I=V/R argument with R being a resistance modeled by the load, but he wasn't swayed by that. :-)
Laptop repair Mosfet substitution - Page 1
Forum section: electronics / beginners

author: zigzagjoe
author_rank: Newbie
timestamp: July 14, 2017, 04:05:14 am
content: Long time lurker, first time post.I'm repairing a Lenovo Yoga 2 11. As is fairly common, it lost a FET in the charging circuit. It'd run off battery (til that went flat) then gave all the signs of a brick. Juice the battery, and it runs some more. Charge controller thinks it's charging, but no current flows. Already performed this repair a couple of times on different laptops.I have identified the faulty FET, aNTTFS4C25N, and for the sake of testing dropped anAON7408in place and observed the expected voltage rise on the battery side. Usedthis testing procedure, it seems to be failed shorted Drain to Source. The FET in question seems to be an intermediate step after the FET that takes 20V in from the AC adapter.Here's a bad picture.PQ202 is the FET in question.Now, the question: I have a number of other FETs available, but not an exact match. I just don't know enough about DC-DC converters to accurately assess if any of them might be a suitable (long term) replacement. I could source the correct replacement from mouser without much issue, so I'm mainly curious. And a little lazy. The AON7400 seems to be reasonably close, but there's some parameters on the datasheets I just don't know about. Charge controller is aBQ24715.Here's what I've got:AON7400AON7408AON7516TPCA8065Thanks in advance for any useful info.
large automotive audio capacitor ripple current rating - Page 1
Forum section: electronics / beginners

author: LaserTazerPhaser
author_rank: Regular Contributor
timestamp: October 14, 2019, 08:55:59 pm
content: How to determine the ripple current rating for those 1.5-8 farad automotive audio capacitors?

author: AVGresponding
author_rank: Super Contributor
timestamp: October 15, 2019, 04:47:41 am
content: If it's of any worthwhile quality, the manufacturers data sheet will include that.

author: LaserTazerPhaser
author_rank: Regular Contributor
timestamp: October 15, 2019, 04:58:22 am
content: Quote from: ThickPhilM on October 15, 2019, 04:47:41 amMost on resale don't have any accompanying datasheets.

author: james_s
author_rank: Super Contributor
timestamp: October 15, 2019, 05:05:31 am
content: I used one in my first attempt at a capacitive discharge spot welder, it lasted about 5 shots and then failed open. They're cheap for a reason.

author: LaserTazerPhaser
author_rank: Regular Contributor
timestamp: October 15, 2019, 05:11:45 am
content: For their dimensions and low voltage they can be made of film.
Large excursions in thermocouple readings with MAX6675 - Page 1
Forum section: electronics / beginners

author: amateur_25
author_rank: Regular Contributor
timestamp: December 23, 2016, 04:44:52 pm
content: I was told the max6675 is supposed to be used with a ungrounded thermocouple.If I wanted to used a grounded thermocouple then the max6675 should be made floating.However despite using a adum5401 (with isolated power), am still getting major excursions when reading the temperature.See the attached for a graph of the readings.The test firmware (i got off the net) uses the max6675 library to read the temperature in Celsius then another separate reading in Fahrenheit .Notice how the line in red sometimes reads a much higher temperature than the ambient in my bed room but this is then not reflected on the blue line.Hence it's a separate reading. This tell me it only occasionally goes berserk.Any help will be much appreciated.

author: GBowes
author_rank: Contributor
timestamp: December 23, 2016, 11:30:29 pm
content: Not sure where you got this idea of isolated thermocouple.The Max6675 data sheet shows a grounded thermocouple in their "typical application"For the Open Thermocouple sense to work the data sheet says that T- MUST be grounded.Note that they do want the ground separate from the CND (pin 1)of the chip.https://datasheets.maximintegrated.com/en/ds/MAX6675.pdfThe data sheet also has some comments about noise that may be contributing to your "large excursions"GrahamQuote from: amateur_25 on December 23, 2016, 04:44:52 pm

author: Marinated
author_rank: Contributor
timestamp: December 24, 2016, 12:43:12 am
content: This is a case where posting a picture of your setup is no less important than posting a schematic. These are sensitive devices and there could be noise coupling into the system from all over the place.

author: shteii01
author_rank: Frequent Contributor
timestamp: December 24, 2016, 05:27:00 am
content: https://www.adafruit.com/products/269"Friends, don't let friends use MAX6675!"

author: amateur_25
author_rank: Regular Contributor
timestamp: December 24, 2016, 01:08:33 pm
content: Maybe some information on why you think the max6675 isn't a good chip?Do you simply mean it's now obsolete?

author: shteii01
author_rank: Frequent Contributor
timestamp: December 24, 2016, 05:46:01 pm
content: Quote from: amateur_25 on December 24, 2016, 01:08:33 pmI have used those boards that I linked, with the MAX31855. Hooked up like they show, two thermocouple wires attached to the ic.
Laser communication from rangefinders.  - Page 1
Forum section: electronics / beginners

author: ArcSin
author_rank: Contributor
timestamp: February 09, 2024, 09:59:16 am
content: Hello.I am pondering on the feasibility to hack the commercially available, of the shelf, laser rangefinder modules in to two way laser communication devices.As I understand, the device itself has all the bits and pieces from the optical standpoint to support good 1 to 2 km communication, or more, considering communicators don't suffer from inverse square law both ways. The thing that is left is to change the circuit that is responsible for measuring in to something that can communicate and filter out its own signal reflections and environment noise while tracking its paired partner. Tracking part could be done with additional optic (some sort of collimation with simplest form of 4 lobe diode or go full steam and do a single sensor IR seeker like system) and some sort of light source on different frequency (or same, using some sort of "beacon" signal inserted in to communication signal) so that function is not crucial for rangefinder to preform. However, am I totally in the woods with my idea or is this even remotely feasible?

author: Andy Chee
author_rank: Super Contributor
timestamp: February 09, 2024, 10:18:35 am
content: FYI, lasers are still affected by inverse square law.https://www.modulatedlight.com/

author: mikerj
author_rank: Super Contributor
timestamp: February 09, 2024, 10:55:55 am
content: Quote from: Andy Chee on February 09, 2024, 10:18:35 amFurther than the Rayleigh length this is true.

author: Marco
author_rank: Super Contributor
timestamp: February 09, 2024, 11:38:16 am
content: Quote from: Andy Chee on February 09, 2024, 10:18:35 amFor power density.You could argue he was referring to link budget. Practically the inverse square law pretty much always applies to link budget for RF but not so frequently for lasers. It's more practical to capture a large part of the beam and the part captured is what's important, not power density.

author: ArcSin
author_rank: Contributor
timestamp: February 09, 2024, 01:09:15 pm
content: What I was trying to say was that the laser system don't need to bounce the laser back to measure the distance, instead it reads other modules laser and reads its data. If it can detect its own beam bounce from 1500m (on youtube there is cool video of fairly cheap unit pulling it off in sunlight), surely, it can detect laser sent directly at it from analogous unit theoretically at 3000m, if not more? (assuming line of sight and atmospherics are ok)Idea is to use the detector on the instrument to listen signal from another rangefinder, that is sending data. And filter its own signal so it wont get confused by reflections in case of two way communication. This will need to be done software side, I know.This way you could transfer bit stream in a fairly tight configuration, depending of how nuts you go with additional steps to prevent the beam divergence.
Laser Cutting - Page 1
Forum section: electronics / beginners

author: Unknown
author_rank: Unknown
timestamp: October 19, 2014, 07:55:10 pm
content: I'm making a custom enclosure by laser cutting "layers" of the enclosure which are held together by vertical rods at the corners. I've done a few of these already and I always end up wasting a load of material on the middle layers because they are just essentially outlines with the middle cut out. Doing it this way however is still cheaper than 3D printing (costs me about 20 quid per enclosure) and I end up with a clear acrylic enclosure, which is hard to get otherwise. The reason I'm posting is because the 6 layers I need to cut have an internal free area of 40mm x 88mm, so if anyone has any "shapes" in 3mm clear acrylic they could use, let me know and I can add them inside the cutout of the middle layers.

author: Precipice
author_rank: Frequent Contributor
timestamp: October 19, 2014, 08:49:04 pm
content: This isn't quite what you asked - but I'd be interested in buying the middles off you!My laser marker (and just-about cutter) has a working area of about that, and it's a pain cutting acrylic down to size

author: zapta
author_rank: Super Contributor
timestamp: October 20, 2014, 07:25:03 am
content: This is a good opportunity for SOB plates with custom cuttings for buttons, connectors, etc.http://dangerousprototypes.com/docs/Sick_of_Beige_compatible_cases

author: Unknown
author_rank: Unknown
timestamp: October 20, 2014, 09:04:34 am
content: Quote from: Precipice on October 19, 2014, 08:49:04 pmI'll be more than happy to send them to you if they'd be of use to you. If you just cover the postage that'd be all I'd ask. I don't have my own cutter, I have to send off to get it done, so I'll drop you a PM when the job is delivered.Quote from: zapta on October 20, 2014, 07:25:03 amThat is very similar to the ones I do, except the corner struts I use are tight fitting clear acrylic rods. They supply enough friction to hold the enclosure together but can be prized apart if need be. I also cut the middle layers as well, they are basically rings with larger corner areas (and some internal layout structure) which of course have a huge internal area wasted, hense my OP. I do indeed cut out buttons and stuff, but I do this from the top panel, the beauty being that the hole cut for the button leaves a cut-out that can be used for the button itself.

author: German_EE
author_rank: Super Contributor
timestamp: October 20, 2014, 08:58:26 pm
content: Laser cutters are one of the best kept secrets in the maker community. Apart from cutting materials they can also be used to engrave front panels at a fraction of normal commercial costs and all you need to provide is a pdf of your job. The plain side of single sided pcb material is ideal for this.
laser diode 3d model in altium - Page 1
Forum section: electronics / beginners

author: alamwte
author_rank: Regular Contributor
timestamp: April 10, 2021, 10:43:58 am
content: Hello,I want to add 3D model of a 4 or 5pin laser diode in altium. But I can not find it. Would you say to me where can I find it?

author: tszaboo
author_rank: Super Contributor
timestamp: April 10, 2021, 10:56:31 am
content: Are you looking for the way to add the 3D model (STEP file) to altium, or are you looking for the step file?

author: alamwte
author_rank: Regular Contributor
timestamp: April 10, 2021, 11:02:54 am
content: I am looking for a way to add the step file

author: tszaboo
author_rank: Super Contributor
timestamp: April 12, 2021, 07:48:08 am
content: You open the footprint, click the menu place-> 3D body.If it is a component from the online altium libraries, you have to download it first.

author: alamwte
author_rank: Regular Contributor
timestamp: April 13, 2021, 08:17:15 am
content: Thank you very much
Laser Diode Driver - Page 1
Forum section: electronics / beginners

author: Zynch
author_rank: Newbie
timestamp: July 29, 2019, 05:15:13 pm
content: HelloI just bought a laser module from China, and it came with a different driver board than advertised, so now I need some help in modifying it.What I plan to do:- Connect it to a LiPo cell and a TP4056 charging/protection module- Move the switch to between the battery module and the driver board (the tactile switch is very impractical for my application)- Add a potentiometer, so that I can change the output power (I would like to change the power so that it will be the lowest usable to save on battery)My questions:- Do I need to have a fixed 3V supply, or can I connect it directly to the battery?- Which resistor would I substitute for the potentiometer? (I presume it would be R4 or R3)Attached is my reverse engineering of the driver board, C1 is not populated.

author: jmelson
author_rank: Super Contributor
timestamp: July 29, 2019, 07:04:52 pm
content: This circuit drawing may have errors. it seems to be a circuit that regulates current through R7 (the 1 Ohm resistor), and maybe controls laser diode current by overloading the battery. probably some connection is drawn wrong.Jon

author: Zynch
author_rank: Newbie
timestamp: July 29, 2019, 08:05:21 pm
content: Yeah, I also thought that my drawing has some issues, checked it twice, but the small size and a lacquer coating do not help either (was using continuity on my DMM to check).I presume there are some vias under the LM358 and or the transistor that are giving me trouble.Also here are both sides of the driver board if it helps somehow.

author: Raj
author_rank: Frequent Contributor
timestamp: August 19, 2019, 12:46:18 pm
content: Laser diode needs constant current. How many amps does your laser consume? You may use single lm338 based current limiter for upto 500mAI've even used multiple lm338 for powering a 3amp laser, but that setup is very bulky (photos attached)

author: rajhlinux
author_rank: Contributor
timestamp: August 24, 2023, 12:48:30 am
content: Quote from: Raj on August 19, 2019, 12:46:18 pmWhat was the hot glue used for?

author: Raj
author_rank: Frequent Contributor
timestamp: August 29, 2023, 05:12:52 pm
content: Well, I was worried about mechanical movement, it sure will reduce heat sync efficiency but around 300mA 2v drop ain't a big deal, It was just a badly made prototype.Update: I've switched to using multiple amc7135 and use a single long heatsink clamped onto them to cool them all.

author: BillyO
author_rank: Super Contributor
timestamp: August 29, 2023, 10:14:01 pm
content: That schematic is definitely wrong. The current through diode would have to be going through the pass transistor. Also, the power for the op-amp would not pass through a 60 ohm resistor. Plus there is no feedback and the two inputs to the op-amp are at different voltages.
Laser Diode Driver on a flexiblePCB - Page 1
Forum section: electronics / beginners

author: Pomflord
author_rank: Newbie
timestamp: September 03, 2025, 04:50:39 pm
content: I am trying to make a laser diode driver that fits on a strip of flexiPCB due to size and fitting constraints.I am a complete amateur and am mostly using ChatGPT to fumble my way through.Board sizing constraints:Width: 6mm maximumDepth: 2.5mm MaximumLength: 30mmIt has to be flexible because it's sitting on a curve.The Diode:Ushio HL65213HDhttps://www.ushio.co.jp/en/products/product_file/file/UIE_DS_HL65213HD.pdfBattery:Grepow GRP1254N1I may do a more powerful custom battery due to sizing constraints.I am aware it isn't enough, i was planning to push it to 15-20c, grepow says it can do 10c safely, alternatively i may downgrade to a 500mw laser diode.BOM:Core:Driver IC: LTC3454EDD#PBFInductor: Coilcraft XFL3012-152MEC (1.5 µH, 3×3×1.2 mm)Rsense: Vishay WSLP0603R1000FEA (0.1 Ω, 0603)Caps:Murata GRM188R60J226MEA0D (22 µF, 6.3 V, 0603)Murata GRM155R60J105KE19D (1 µF, 6.3 V, 0402)Murata GRM155R71C104KA88D (0.1 µF, 16 V, 0402)Murata GRM188R60J475KE19D (4.7 µF, 6.3 V, 0603 for VIN bypass)Protection / Filtering:Littelfuse SP0502BAHTG (0402 TVS)Murata BLM18PG221SN1D (0603 ferrite bead)TDK NTCG104LH104JT1 (100 kΩ NTC, 0402)Resistors:100 kΩ pull-up (CRCW0603100KFKEA or similar) for CTRL pinMostly i am just looking for feedback, is what i am doing possible?Are the components i selected workable?Do you see any problems i might encounter?i have no idea what im doing for the most part but am learning as i go.

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: September 04, 2025, 02:56:00 pm
content: If possible, please make a circuit diagram and simulate the circuit. You can use P-spice or proteus.

author: Marco
author_rank: Super Contributor
timestamp: September 04, 2025, 03:36:26 pm
content: Quote from: Pomflord on September 03, 2025, 04:50:39 pmSo you are fitting the flex in first and then soldering?
Laser Distance Measurment - Page 1
Forum section: electronics / beginners

author: j.a.mcguire
author_rank: Contributor
timestamp: July 15, 2015, 07:11:06 am
content: Would anyone have a recommendation on a microprocessor which would be suitable for measuring distance with light? I wondered if there are ADCs which are stand-alone and could sample a photodiode with a nanosecond interval and fill a buffer when a detection is made which could then be sampled perhaps a few hundread times a second by a standard micro over serial?Can this be done relatively inexpensively?

author: lukier
author_rank: Unknown
timestamp: July 15, 2015, 08:20:25 am
content: I doubt you would be able to find a microcontroller with > 100's MSPS ADC and that's what one can usually find in laser scanners.Laser scanners, if I remember correctly, use either phase measurement (like ToF cameras -http://www.ti.com/lit/ml/sbau219d/sbau219d.pdf) or some switched capacitor trick (like interpolator circuit in a frequency counter).Probably the simplest and cheapest laser rangefinder is what is used in Neato vacuum cleaner -http://www.robotshop.com/media/files/PDF/revolds-whitepaper.pdf.

author: f5r5e5d
author_rank: Frequent Contributor
timestamp: July 16, 2015, 05:14:32 am
content: time of flight is tough without purpose built hardwarewith of the shelf electronics speeds triangulation is popular with linear PSD or line element sensors

author: amyk
author_rank: Super Contributor
timestamp: July 16, 2015, 06:00:55 am
content: https://www.eevblog.com/forum/chat/how-does-laser-meters-work/

author: tggzzz
author_rank: Super Contributor
timestamp: July 16, 2015, 07:23:09 am
content: It is relatively easy to measurepicosecondintervals - look for "time to digital" converters.Before you spend too much time implementing it, you will have to consider how to distinguish photons from your light source from any other photons that happen to hit the detector. Be very very careful with safety: 5mW (depending on wavelength and other things) is the maximium amount considered safe from a laser. Yes, you can easily get 400mW and 1W diodes, but they are definitely not safe.If you use a powerful laser (i.e. >5mW) then you should protect those around you by looking directly at it the first time you swiitch in on - it will blindyouand thereby stop your experiments before they damage innocentbystanders!
Laser engraver power cap - Page 1
Forum section: electronics / beginners

author: onis_uk
author_rank: Contributor
timestamp: March 23, 2024, 01:26:12 pm
content: Hi all,I've got a cheap Laser engraver, Atomstack S10 Pro. It works great but does seem to struggle with power delivery when I get over 80% power, I can see the power led in the control board dimming when the laser is on. The main board is a "Laser box ESP32 V1.0".There is a +12V plug going from the control board to the laser, I was wondering if I could put a cap across that +12v rail to help with power delivery........?If so, what size should I go for?

author: Vovk_Z
author_rank: Super Contributor
timestamp: March 24, 2024, 07:06:27 am
content: Why do you have to feed it with 80% of requred voltage istead of 100%?.

author: onis_uk
author_rank: Contributor
timestamp: March 24, 2024, 02:49:05 pm
content: you misunderstand, when you use a laser etcher you select that power output in software for the material you are using. When I'm marking stainless steel, the best results I've found at 85% of peak power.But like I say, this seems to cause some power/voltage sag hence me wanting to bolster the 12v rail with a cap...

author: MarkT
author_rank: Frequent Contributor
timestamp: March 24, 2024, 07:08:52 pm
content: A capacitor can only help with very brief power overloads, not sustained overload. Perhaps the PSU is inadequate, perhaps the wiring? Perhaps the laser is pulling more current than expected?

author: Vovk_Z
author_rank: Super Contributor
timestamp: March 25, 2024, 10:28:19 am
content: Quote from: onis_uk on March 24, 2024, 02:49:05 pmThis is a typical behavior when different materials want different modes. There is a large possibility you want to add a cap because you have free hands and excessive free time, I guess.

author: onis_uk
author_rank: Contributor
timestamp: March 25, 2024, 05:28:02 pm
content: wow soooooo helpful...

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 07:47:14 pm
content: Quote from: onis_uk on March 25, 2024, 05:28:02 pmAlright. Hopefully my answer is more helpful: no adding a capacitor across the power supply rail, will not increase the power.Is this a brand new item? Have you contacted the seller?
Laser equipment - Page 1
Forum section: electronics / beginners

author: argengraph
author_rank: Newbie
timestamp: May 13, 2019, 08:56:21 pm
content: I need to downsize particles to the nanometer level bylaser ablation in liquid and I have the following information:Ten shots of laser (0.1 J each pulse energy) irradiated usinga laser source with a power density of 1.2×10^9 W/cm2horizontal pulsed laser beam (355nm, third harmonic, 10ns pulse width)at a repetition rate of 10Hz focusing the pulsed laser beam to adiameter of around 1mm.Is this information enough to determine a laser equipment ?

author: dmills
author_rank: Super Contributor
timestamp: May 13, 2019, 09:58:08 pm
content: Third harmonic YAG laser, Q Switched, of the fairly short pulse kind.0.1J in 10ns is a fairly high peak power level, 10MW peak, 1W average unless I have dropped a decimal somewhere? Might be some pulse compression involved to get the peak power level?NOT going to be cheap.Coherent are a likely vendor for a (probably) optically pumped YAG, but I also wonder about exceminer lasers as possibly a cheaper short UV pulse source, got issues of their own, but might be worth a look.Another thought is N2 gas lasers, might struggle with the PRF but they are fairly cheap as these things go, and have copious peak power in the UV.

author: ejeffrey
author_rank: Super Contributor
timestamp: May 14, 2019, 03:57:44 pm
content: Quote from: argengraph on May 13, 2019, 08:56:21 pmThese are fairly standard specs for applications like laser ablation. Spectra-physics has an assortment of suitable lasers:https://www.spectra-physics.com/products/high-energy-pulsed-lasers/Coherent will have a similar assortment. Be prepared to pay $$$. I haven't shopped for high power lasers in a long time and never this sort of application, but my rough guess is $100k? It will also depend on whether you are an industrial or academic customer.As dmills said, there are other options that are cheaper, but will require more leg work on your side to figure out what is appropriate. You might also have to do some more process development if you end up with a laser with different pulse energy, wavelength, or pulse length. You might also be able to find one used for a lot less, but in variable condition. Still, you might be able to get a used laser, clean or replace a few optics or buy a new set of pump diodes and be in business. Those are expensive, but a lot less than the full laser.
LASER printer and DVD writer LASER diode list (common used diode sources) - Page 1
Forum section: electronics / beginners

author: Tony777
author_rank: Newbie
timestamp: March 25, 2019, 05:23:33 am
content: I was had a few old laser printers and was wondering if there is a list somewhere of the laser diodes in common laser printers and DVD writers, other common laser equipment items and if they are IR or visible diodes. I tried Sams Laser Faq but it didn't have any info. Does anyone know or even have an idea of the power level and wavelength/color? Specifically for the Laserjet 6L, Canon LBP860, and common DVD writers. Can someone please help?

author: castingflame
author_rank: Regular Contributor
timestamp: March 25, 2019, 07:04:10 pm
content: AFAIK a bit percentage of 'Laser' printers are LED not Laser.Sent from my SM-N960F using Tapatalk

author: james_s
author_rank: Super Contributor
timestamp: March 25, 2019, 09:51:23 pm
content: Laser printers that are smaller than a car invariably use rather boring low power IR diodes, a lot of compact printers are as mentioned above, LED page printers. These are often referred to as "laser class". DVD and Bluray drives use visible lasers, red and violet respectively. Writers have much more powerful lasers than readers.

author: SL4P
author_rank: Super Contributor
timestamp: March 25, 2019, 10:14:01 pm
content: Your ‘free’ device storage is probably costing more over the long term than buying new laser diodes when you need them.You have no specs or quality info on ‘old’ parts. This can have significant consequences.Lasers are as cheap as - until you push up past 1W...
Laser printing DIY PCBs - Page 1
Forum section: electronics / beginners

author: Sounduser
author_rank: Contributor
timestamp: March 09, 2015, 10:03:48 pm
content: Hi,Ive been playing with laser printer single sided PCBs. Using the paper than sickers come on. Its working fine.I was wondering, what is the best thing to touch up traces with?Sharpie pens dont really hold up while etching. I was thinking some kind of paint and very fine paint brush. Just to go over any holes in the print.Thanks.

author: rdl
author_rank: Super Contributor
timestamp: March 10, 2015, 12:20:44 am
content: Paint and a fine tipped brush will work pretty well. Back in the 80s I painted a lot of small, simple circuit boards. You can get very fine tipped brushes at a hobby shop, or buy online. Most model paints will work. Even fingernail polish (which is actually a kind of lacquer) will work. Be sure to get some thinner or brush cleaner, too. Make sure you give the paint plenty of time to dry before putting the board in the etchant.

author: picandmix
author_rank: Frequent Contributor
timestamp: March 10, 2015, 12:27:51 am
content: Find the type of permanent pen that you write on to CDs etc work fine, the one I currently have is labelled Stabilo Write 4 All.Also the Staedtler Lumicolor Permament should do as well.For cleaning, thinners as rdl mentions , what I use, Acetone or cheap Nail polish remover, but use soapy water if using the latter as it contains oilsNot sure what country you are in , so these brands might not be in your area...

author: tautech
author_rank: Super Contributor
timestamp: March 10, 2015, 12:39:50 am
content: Quote from: Sounduser on March 09, 2015, 10:03:48 pm2 possible issues IMO.The copper is not clean enough, sand with 600 to 1000 grit paper or steel wool. Wash & dry. Some pre-etch to get a better toner stick.More heat and/or pressure in the transfer process.Pouch laminator gives the most consistant results. 2 passes.
laser vibration measurement? - Page 1
Forum section: electronics / beginners

author: engineheat
author_rank: Frequent Contributor
timestamp: April 24, 2020, 03:07:22 pm
content: Hi,I like to analyze the sound of an electrical device such as a power shaver. I was able to do so using a microphone and analyzing the raw sound wave signal and its FFT. The highest frequency of interest is around 7khz.But microphone is subject to random ambient noise. I wonder if there are touchless solutions such as laser that can give me a similar signal? I'm not familiar with laser devices or its max. sampling rate.Money is not too big of a factor...Can anyone advise?Thanks

author: RoGeorge
author_rank: Super Contributor
timestamp: April 24, 2020, 03:20:16 pm
content: It is calledLASER vibrometry, it can be made in 3D, too, to see for example how a surface bend and twist during vibration.

author: engineheat
author_rank: Frequent Contributor
timestamp: April 25, 2020, 05:22:14 pm
content: Thanks. Will the measurements from such laser device be similar to that of a microphone? In another word, if the physical vibration of a sound producing object directly relational to the sound wave?Also, are such unit capable of high enough sampling rate for my purpose? Just want to get some background knowledge before I do deep research.thanks
Laser Current Source with Voltage Clamp - Page 1
Forum section: electronics / beginners

author: Allenz
author_rank: Newbie
timestamp: August 05, 2021, 09:10:30 am
content: Welcome! My friendsRecently I am dealing with a CW laser driver circuit.It is a current source that can be controlled by a DAC voltage.In order to protect the laser in abnormal conditions，Such as open circuit and re-connected，I want the compliance voltage to be tunnable，So this could be a source worked in both CV/CC mode. I will just clamp the voltage to a value just a little higher than needed so the laser will not be damaged.It seems some product use crowbar to short the output if over voltage is detected. But I think a programmable threshold with a limited layout space fits my requirement.I need control Laser current and measure its actual current and forward voltage.The ideal component used are as following, which is space saving when using small footprint components:2ch opamp x1 OPA376 usedcurrent amp x1 INA186 usedMosfet x1R C L **Problems:TINA-TI Transients simulated OK, but actual PCB soldered will oscillate at some clamped voltage.(especially when 0 < Laser current < Iset, Seems when clamping and current regulating both are taking effect.)I've read DIY_SMU projects and it use crossover circuit to control output poweramp, but I did not quite understand the real detail.As you can see, I am not good at analog circuits. Looking for your suggestions on this~
Last non internet version of autodesk eagle - Page 1
Forum section: electronics / beginners

author: ME
author_rank: Frequent Contributor
timestamp: April 11, 2025, 01:02:36 pm
content: Would anyone know what was the last version number of autodesk eagle that can be used standalone without having to call home or log in/on?.

author: KE5FX
author_rank: Super Contributor
timestamp: April 11, 2025, 04:59:51 pm
content: 7.7.0, AFAIK.