hybridfree/eevblog-posts huggingface dataset:
Tooth paste thermal paste corrosion - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: July 20, 2019, 05:59:02 am
content: I have about 50mL of thermal paste for CPU's, in a needle, but I can't find. So on a 2n3055 I used toothpaste, between the heatsink, and insulator.It never shorted. There are 2 dark brown rings around the outside, of the insulated circles, where the base and emitter pins emerge. Something has chemically reacted.

author: Towger
author_rank: Super Contributor
timestamp: July 20, 2019, 06:14:41 am
content: Probably water in the toothpaste.Zinc oxide creams would probably be a better household substitute, of the type uses on babies bottoms. Eg Sudocremhttps://en.m.wikipedia.org/wiki/Sudocrem

author: Dabbot
author_rank: Regular Contributor
timestamp: July 20, 2019, 06:27:58 am
content: Quote from: lordvader88 on July 20, 2019, 05:59:02 amQuote from: lordvader88 on July 20, 2019, 05:59:02 amThis is amazing. Did your "toothpaste" taste funny this morning?

author: lordvader88
author_rank: Frequent Contributor
timestamp: July 20, 2019, 06:42:30 am
content: I should take a picture, can I upload it directly upload it off my PC? I think I can and did that on here before

author: tggzzz
author_rank: Super Contributor
timestamp: July 20, 2019, 06:55:00 am
content: Quote from: lordvader88 on July 20, 2019, 06:42:30 amDon't bother. It won't show anything surprising or interesting.

author: magic
author_rank: Super Contributor
timestamp: July 20, 2019, 07:04:21 am
content: Amateur. You should have known to you mayonnaise.https://www.hardwaresecrets.com/thermal-compound-roundup-january-2012/5/

author: Whales
author_rank: Super Contributor
timestamp: July 20, 2019, 07:15:48 am
content: I've used toothpaste before. Two problems:(1) Water based(2) Some are grittyWater is a really good thermal transfer material, but it dries out quickly. Grit of course spaces things, YMMV may vary depending on the toothpaste.For actual test results: seeDansData. Excerpt:[ Specified attachment is not available ]I'll agree with water-based corrosion, but it will also be residue of soaps and other toothpaste materials. Clean it off and things should be good. No thermal paste might be a better long term option than water-based compounds.
TOP224YN - Page 1
Forum section: electronics / beginners

author: abpfischer
author_rank: Newbie
timestamp: July 16, 2022, 04:46:57 am
content: What does the TOP224YN do? I have a Miele Coffee machine and the electronic board has one of these that has split and cracked in half. The machine no longer powers up so I thought I might be able to replace this? There seems to be a residual voltage left through here from the capacitor.P.S. I am a complete novice.

author: mindcrime
author_rank: Unknown
timestamp: July 16, 2022, 05:14:56 am
content: Per thedatasheetit's a PMIC (Power Management IC) dedicated to some part of the PWM (pulse width modulation) implementation. Mouser at least don't show anyin stockbut they are available for backorder which suggests that the part is at least still made. Another vendor might even have some in stock.And even if you can't find the original, if it's popular enough, you might find a clone or pin-compatible replacement from another manufacturer, either a reputable one, or one of the One Hung Lo brand "Shenzen Market" type deals on Aliexpress. Either way, if you can find one, it probably wouldn't hurt to desolder the existing broken one and replace it. If that's the only damage to the machine, that might well fix it. No guarantees, of course.

author: Per Hansson
author_rank: Unknown
timestamp: July 16, 2022, 07:30:14 am
content: This is the main switcher in smaller power supplies, often used also in ATX power supplies for the 5v standby voltage when the PC is off.Is exists in both DIP-8 version, and a TO-220 version as you have here, their market name is "TOPSwitch-II"Multiple wattage ratings exist, and they are compatible.So you could replace yours with any of the higher rated models also: TOP225YN TOP226YN TOP227YNHere are some in stock:https://www.digikey.com.au/en/products/detail/power-integrations/TOP226YN/865234https://au.mouser.com/ProductDetail/Power-Integrations/TOP227YN?qs=Jph8NoUxIfXIgzaSioLUnw%3D%3DP.S: Look at the example schematic in the datasheet posted by mindcrime above:Check to make sure the diodes have not failed also, it is very likely when the device shorts...It could also have let voltage out the control pin, so you should check the optocoupler and its associated resistors and diodes too.

author: Gyro
author_rank: Super Contributor
timestamp: July 16, 2022, 09:14:08 am
content: Please be very cautious about working on the mains side of the circuit if you are a novice. You mentioned the residual voltage on the capacitor - the primary side reservoir cap will be left charged to mains peak voltage (around 340V) under these circumstances and will bite. Ensure that it is fully discharged before working on the board or after testing.It is possible that something on the secondary side of the small SMPS transformer has caused the IC to fail due to overload. The rectifier diode and output capacitor are possible candidates. You it would be wise to check all component in the PSU area as a precaution before changing the TOP244.
TOP853 EPROM programmer - Page 1
Forum section: electronics / beginners

author: minim
author_rank: Contributor
timestamp: January 28, 2018, 09:27:01 pm
content: I got a old CNC mill with fanuc control system. The program needs editing and I have a guy with fanuc software that can help me do this. The only problem is that fanuc has made a "EDITING CASETTE" to read out the program from the two chips and into their software. I found one off ebay for $1400 and that's heavy for one time use. I've been looking at this TOP853 programmer. Will it do the job?The EPROMS are marked "TC57256AD-15" and on this is the list of supported devices on the TOP853. I found a number where the last three digits are zero that fits mine but I can't figure out what the "256AD" is for. The "-15" in the end of the number is for 150ns access time according to the datasheet.____EPROM-TOSHIBATMM2716-25V, TMM2732-21V, TMM2764-21V, TMM2764A-12.7V, TMM27128-21V, TMM27128A,P27,TMM27256A,P27, TMM27256AD,P27, TMM27512,P27, TC541000,P27, TC541001,P27, TC571000,P27,TC571001,P27, TC532000,P27,TC572000,P27, TC534000,P27, TC574000,P27,

author: amyk
author_rank: Super Contributor
timestamp: January 28, 2018, 10:19:20 pm
content: 256 is the size. 256Kbit (32KByte).Do you need to actually program one, or just read it? Because the latter can be done with just about anything including an Arduino, and looking at the datasheet the former is going to be possible with any EPROM programmer that can use the standard algorithm for 27C256 and the like. (Vcc=6V, Vpp=12.5V, 1ms program pulses.)

author: cowasaki
author_rank: Frequent Contributor
timestamp: January 29, 2018, 12:23:12 am
content: The TC57256AD-15 has the same pinout as the 27256 even my cheap VP-180 will read it!This is an EPROM programmer that will do what you want for under £30 and if you only use it once you could stick it on here for sale and get a big chunk of that back.https://www.ebay.co.uk/itm/High-Speed-Tl866cs-Programmer-Usb-Eprom-Eeprom-Flash-Bios-Avrpic-New-Ic-W/132187475108?_trkparms=aid%3D555019%26algo%3DPL.BANDIT%26ao%3D1%26asc%3D20151005190540%26meid%3D4444ccd7744d4dd1a1bf157c3e5d5bfb%26pid%3D100505%26rk%3D1%26rkt%3D1%26%26itm%3D132187475108&_trksid=p2045573.c100505.m3226Here it is with more options at under £35. I'd give you £25 for it after you've finished with ithttps://www.ebay.co.uk/itm/TL866CS-Programmer-USB-EPROM-FLASH-BIOS-6-Adapters-Socket-Extractor-For-13000-AM/253076064515?epid=4007878372&hash=item3aec824903:g:cAoAAOSwPK5ZgsM6

author: cowasaki
author_rank: Frequent Contributor
timestamp: January 29, 2018, 09:32:22 am
content: I have a vp180 and use a virtual machine on two of my macs for the software. When I eventually upgrade the programmer I will make sure it runs on 64bit windows 10.

author: minim
author_rank: Contributor
timestamp: October 08, 2018, 07:01:24 pm
content: I should post back that it worked out with the programmer in the first post. Sorry for the late replyGot the program read out, changed and uploaded to a new chip that is now sitting in the machine
TOPswitch - Page 1
Forum section: electronics / beginners

author: khatus
author_rank: Regular Contributor
timestamp: August 07, 2018, 06:35:18 pm
content: Why TOPswitch is called TOPswitch?? Why the word TOP is used??

author: tsman
author_rank: Frequent Contributor
timestamp: August 07, 2018, 06:44:51 pm
content: It is just a name they chose. Power Integrations has several different product ranges that are called somethingSwitch.
Toroid-less Joule Thief – Align the phase of the two discrete inductors? Solved - Page 1
Forum section: electronics / beginners

author: t1d
author_rank: Super Contributor
timestamp: October 20, 2023, 11:16:04 am
content: This is a Joule Thief experiment using two resistor-style inductors, instead of a single, double-wound, toriod-style choke. It works, by simply abutting the two discrete inductors.Two 3mm, red LEDS. PSU set to 0.6VDC and CC set at 0.01A. The LEDs illuminate nicely and the CC does not engage.I know that, for a Joule Thief, the phase of the windings on a toroid must be maintained. I wondered if that is true for the discrete inductors. So, I tried to test their polarity, as I would for a transformer’s windings, using my function generator and my scope.I connected the Fun Gen in series to a 50 Ohm resistor (an attempt at termination, which I do not fully understand, yet) and connected that to one side of the first inductor. I grounded the other side. I isolated the second inductor from the first and abutted them. Then, I read across each of them with a separate scope channel. Then, I flipped the second inductor, end for end, and took additional readings. I also scoped the fun gen reference input on a third channel.. All grounds were common.The results were inconclusive. The phases of the two inductors’ scope traces looked to be oriented the same, un-flipped and flipped. However, I know that appearances can be deceiving...So, here are the questions…- Does the phase orientation of the two discrete inductors matter, for a Joule Thief?- If so, what would be an appropriate procedure for testing their phases/polarities?Thanks for your help.

author: wraper
author_rank: Unknown
timestamp: October 20, 2023, 11:30:34 am
content: Flipping an axial inductor does not change winding orientation. Changing the leads connected to the circuit while keeping inductor position the same does.

author: t1d
author_rank: Super Contributor
timestamp: October 20, 2023, 11:55:54 am
content: Quote from: wraper on October 20, 2023, 11:30:34 amThanks, wraper! That explains what I saw. In that case, as long as I have the referenced circuit wired correctly, the orientation of the discrete inductors is not significant.It is a mesmerizing effect and circuit...Cheers!

author: wraper
author_rank: Unknown
timestamp: October 20, 2023, 12:12:12 pm
content: Quote from: t1d on October 20, 2023, 11:55:54 amAs long as both inductors are of the same type. I did not check winding direction in various off the shelf inductors but nothing prevents inductors to be wound in different direction.
Toroid source - Page 1
Forum section: electronics / beginners

author: theoldwizard1
author_rank: Regular Contributor
timestamp: May 24, 2020, 12:56:02 pm
content: I would like to start experimenting with some of the inexpensive sine wave inverter boards available on eBay. From my research, the most "robust" design uses a large transformer to boost the low voltage, high current sine wave to mains voltage. The problem is finding asource for large ferrite toroid cores or at least silicon steel sheet that you can wind into a core.I would consider buying a wound transformer, but I can not find those (in the size I would want) either.

author: ArthurDent
author_rank: Super Contributor
timestamp: May 24, 2020, 01:26:58 pm
content: Ferrite cores are not used for mains frequency transformers.

author: theoldwizard1
author_rank: Regular Contributor
timestamp: May 24, 2020, 01:42:44 pm
content: Quote from: ArthurDent on May 24, 2020, 01:26:58 pmThanks ! I know nothing about magnetics !

author: strawberry
author_rank: Super Contributor
timestamp: May 24, 2020, 06:12:36 pm
content: Laminated steel core.HiFi tube output transformer design is good way to start .

author: WattsThat
author_rank: Frequent Contributor
timestamp: May 24, 2020, 07:19:22 pm
content: Wound tape toroidal cores are available on eBay. Primarily for the hi-if bunch wanting to wind their own transformers so they’re not the cheapest but an easy source for a one-off.

author: theoldwizard1
author_rank: Regular Contributor
timestamp: May 25, 2020, 12:29:15 am
content: Quote from: WattsThat on May 24, 2020, 07:19:22 pmeBay search "toroidal laminated core"

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2020, 05:26:40 am
content: I've bought iron toroid cores from Bridgeport Magnetics, I think that was about 10 years ago though so I don't know if they're still around. Winding a toroid by hand is tedious, although at least larger ones need fewer turns than small ones.
Toroid vs ETD Ferrite Cores - Page 1
Forum section: electronics / beginners

author: rentner
author_rank: Regular Contributor
timestamp: April 17, 2013, 05:21:34 pm
content: In almost any Power supply with switching going on, you will have two type of cores:Toroids - Used for removing noise.ETD's - The standard Type of ferrite Transformers used in almost any Supply today and even back in the good old 20th century.Why not use one of both types for the same purpose? Does this have advantages in price or efficiency?

author: Neilm
author_rank: Super Contributor
timestamp: April 17, 2013, 06:53:31 pm
content: They generally have very different characteristics. It all depends on what they are being used for. For example a toroid will have a low leakage. A normal ETD core can have the leakage adjusted - either by grinding down the center leg or putting small shims on either side. If designing a flyback SMPS for instance, the energy you can transfer is down to the leakage in the transformer.Neil
Toroidal Transformer LinearPi Pro Bluesound Node Nano setup project - Page 1
Forum section: electronics / beginners

author: profusion
author_rank: Newbie
timestamp: March 21, 2025, 02:27:15 pm
content: Hi to all you electronic gurus out there! I need your help in a small project I started but have not completed do to risk of screwing up and burning out my new gear. I need confirmation/correction for what I have laid out already.Background info:I have a Bluesound Node Nano and later found out I can achieve better quality in the audio from simply changing out the power supply. I wanted to do a more budget friendly option and found out that I can use a LinearPi Pro and a toroidal transformer to gain some good results compared to an already plug-n-play Sbooster alternative.Now that is out of the way I have attached diagrams and pictures of everything to provide hopefully everything you will need to help me figure this out correctly and not miss anything. if you need more details let me know!Thank you all in advance!

author: awesomechapro
author_rank: Contributor
timestamp: March 21, 2025, 02:31:29 pm
content: All looks good to me, assuming you have removed both of the jumpers on the board.

author: profusion
author_rank: Newbie
timestamp: March 21, 2025, 02:45:00 pm
content: Thanks! Now what would happen if I didn't remove the jumper and plugged in the power? less power or burn something out?

author: awesomechapro
author_rank: Contributor
timestamp: March 22, 2025, 02:16:01 am
content: If you dont remove S2 before plugging it in, it will be configured for 5V and you will likely damage something. Remove S2 and it should be correctly configured for 12V.
Toroidal transformer - problem at connecting - Page 1
Forum section: electronics / beginners

author: mike_mike
author_rank: Super Contributor
timestamp: December 07, 2019, 03:38:19 pm
content: Hi, I received a toroidal transformer that had the secondary 2x24V / 100VA with median socket. This secondary has been opened in order to be able to connect in parallel the two 24V windings resulting from the opening of the median socket. Unfortunately, the two windings were connected incorrectly and the transformer was powered this way for a few seconds and it heated up (but not very much). Then it was disconnected from the 230V network.I checked it, it is functional, both secondary have the voltage of 25.5V with no load when 230V at network.I checked the primary by measuring with the Ohmmeter and comparing it with another transformer that had the primary winding for the same voltage, and the results were very close.Also, I also checked using the Ohmmeter the secondary and both had the same resistance.Then I connected in parallel the 2 secondaries (this time correctly) and I powered the transformer and let it powered for 4 hours and it did not heated up.Are there any other ways I could figure out whether or not there are or will be any problems with this transformer?

author: andy3055
author_rank: Super Contributor
timestamp: December 07, 2019, 05:24:22 pm
content: The only test you can do is an insulation test. Between the windings and from windings to the core (if the core is visible anywhere). For that, you will need something like a megger.

author: Jwillis
author_rank: Super Contributor
timestamp: December 07, 2019, 11:26:14 pm
content: You probably connected the secondaries so they were out of phase with each other . Heating of the transformer would be the result . Most transformers can handle a fair amount of heating as long as the shielding on the coils doesn't melt . Most windings on transformers now use a Polyurethane ,Polyester or Polyimide coating and can stand temperatures from 155C to 180C and Polymides can be higher. That quite a bit of heat. Even 60C can be hard to touch. If your getting the correct readings when the secondaries are configured properly you should be alright.
toroidal wiring - Page 1
Forum section: electronics / beginners

author: harps
author_rank: Regular Contributor
timestamp: November 13, 2017, 09:29:16 pm
content: hiI have a toroidal that i hope to connect mains 230v and have dual 18v as the output.The physical colour of the wires is visually clear and distinguishable poking out of the toroidal.on the sticker it statesPrimary 0-115v 0-115v (blu.gry.pul.brn)&secondary 0-18v (org yel)0-18v (blk.red)am i right in thnking this below is correct.on the primary for 230v :solder grey and purple together.connect mains + to brownconnect mains - to blueon the secondary:solder orange and black together for groundconnect red and yellow to the full bridge rectifier.Thanks for help and/or confirmation : )

author: Gyro
author_rank: Super Contributor
timestamp: November 13, 2017, 09:41:52 pm
content: Yes, that looks correct (not being able to see the label, but from your description its markings are logical and clear).It's always good to be cautious though. Make sure you have a reasonable rating fuse included on the primary side [Edit: or series mains filament lamp, for the first power-up]

author: harps
author_rank: Regular Contributor
timestamp: November 13, 2017, 10:02:45 pm
content: Thank you very much Gyro !!

author: Cerebus
author_rank: Super Contributor
timestamp: November 13, 2017, 11:29:58 pm
content: From the colour codes that sounds like a Vigortronix toroidal transformer. If it is, then yes, that is correct; I have one here (50VA 2 x 0-25V) that has been powered up and has behaved itself that has been wired exactly like that on the mains side.However, you had best check the phasing very carefully on the secondary side, as what you are suggesting sounds like wiring the secondaries in anti-phase, which is most probably not what you want.

author: basinstreetdesign
author_rank: Frequent Contributor
timestamp: November 14, 2017, 12:21:48 am
content: Check the phasing of the primaries, too. If its wrong then you will have a fairly deadly short on the mains and could damage the transformer. If you have access to a low ac voltage, such as 12 Vac, then do this by connecting the two primaries, in series to that ac source and then check the voltage found on one of the secondaries. If it is as expected at Vpri x 230/18 it's good. If it's very low its wrong. Just swap the leads on one of the primaries.You could also use a dim-bulb tester on the primary side if you have one.

author: IanB
author_rank: Super Contributor
timestamp: November 14, 2017, 12:26:45 am
content: Yes, definitely check the phasing of the primaries before connecting to the mains. The consequences of getting that wrong will be quite severe.

author: IanB
author_rank: Super Contributor
timestamp: November 14, 2017, 12:31:30 am
content: Quote from: harps on November 13, 2017, 09:29:16 pmRemember mains doesn't have "+" and "-" as it's AC.Similarly the secondary side doesn't have a ground, it is AC also.It seems that if you connect orange and black together, and then connect yellow and red together, you will have 18 V AC at the full rating of the transformer. But do check the phasing to make sure before you do that.
Torque control for brush DC motors - Page 1
Forum section: electronics / beginners

author: solaremperor
author_rank: Newbie
timestamp: March 03, 2018, 12:23:38 am
content: Hello everyone - first time poster here!In the lab I work in, we run brush DC motors to drive wire-driven humanoid robotic hands. So, the motors need to run in torque mode and in stall. But, they should also be capable of fast wind-up speeds (but speed need not be regulated).Currently, we use linear servo amplifiers (Western Servo Design LDU-S1:wsdi.com/ldu-s1.htm) to drive brush DC motors in torque mode. These things are very old and have reached their EOL, so I have been tasked with finding a suitable replacement. So, I am trying to learn how they work and find suitable replacements. I would much appreciate it if the community could help me demystify the operation of linear servo amplifiers and/or help me find answers to the following questions.How are these servo amplifiers different from PWM servo drives?Also, how is it that the LDU-S1 is able to claim that it has numerous advantages over PWM type amplifiers including minimum motor heating, increased brush life and the ability to drive zero inductance loads?Finally, the LDU-S1 uses the PCU-S1 (wsdi.com/pcu-sx.htm) which claims to use shunt regulators to prevent back EMF generated by the motors from damaging components in the Bus Supply and amplifiers when using PWM amplifiers. What circuits enable this?I am willing to roll out custom PCB designs too, so circuit design ideas are welcome! If I've accidentally broken posting rules or you need more information, please let me know and I will try to edit the post and fix the issues.Thanks,Solaremperor

author: fourtytwo42
author_rank: Super Contributor
timestamp: March 03, 2018, 09:43:42 am
content: There is someone on this forum who is a servo expert BUT I can tell you these are linear constant current drives very different from PWM that is a chopped signal only suitable for some motors.I don't quite understand what you mean by EOL, if the units have failed they are easely repairable so why re-invent the wheel ?

author: LaserSteve
author_rank: Super Contributor
timestamp: March 04, 2018, 04:52:15 am
content: You might want t start with some Apex MicroTechnology Application notes on Brushed Motor Drive.Steve

author: solaremperor
author_rank: Newbie
timestamp: March 04, 2018, 07:29:46 am
content: Thanks Fourtytwo42 and LaserSteve!
Total current flowing through inductors in PARALLEL - Page 1
Forum section: electronics / beginners

author: LinkZ
author_rank: Contributor
timestamp: April 19, 2015, 10:28:04 am
content: Hi, I need a 68uH 3A inductor and i want to connect in parallel two inductors (100uH+220uH) to obtain the value. Each inductor in rated differently: the 100uH have 2.1A current, while the 220uH one is rated 1.4A. Now i want to know if both inductors wired in parallel can substain a current of 3A. DAMN, i didn't find anything about this argument

author: PA0PBZ
author_rank: Super Contributor
timestamp: April 19, 2015, 10:33:50 am
content: I guess you are talking DC current, in that case the current will divide over the 2 inductors according to their DC resistance which is unknown at the moment.

author: LinkZ
author_rank: Contributor
timestamp: April 19, 2015, 11:09:05 am
content: Yes, DC current. Inductors are these:http://www.futurlec.com/Power_Inductors.shtml

author: Anand
author_rank: Contributor
timestamp: April 19, 2015, 12:07:40 pm
content: Measure the resistance of your inductors and you can use this rule:http://en.wikipedia.org/wiki/Current_dividerIf you can't measure it, take it from the datasheet.If it's not in the datasheet...Also, there is a problem when switching occurs: the lower value inductor might (or might not) take a large amount of current before the bigger one so, by combining a 100uH / 2.1A with a 220uH / 1.4A one you might get a 68uH / 2.1A inductor, not a 3A one.Last edit:You should make a simulation to test these things out.I think a 100uH (15mOhm series resistance) and a 220uH (35mOhm series resistance) are a good start values.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 19, 2015, 04:01:42 pm
content: Loops between low resistance components (like inductors and transformer windings) are best avoided. In the ideal case, where DCR = 0, the current in that loop is independent of the rest of the circuit, and in a SPICE simulation, you usually get a "singular matrix" error because it doesn't have any way to solve for that unknown current.So, you're better off using two 33uH chokes in series.Another point of note: if the inductors are not well shielded, the value obtained may be quite a bit different from the expected value (in series or parallel), due to coupling.Tim
Total Newby and Meter Recommendation Please.  - Page 1
Forum section: electronics / beginners

author: baddarryl
author_rank: Newbie
timestamp: January 29, 2017, 05:01:25 pm
content: Hi all. I am scratching an itch that I have had for a long time. I am fairly mechanically inclined however un knowledgeable in general of electronics. I know how to do basic things like check voltage, resistance, and current on different things, but my knowledge is limited. I found EEVblog on youtube and have starting following and reading as much as I can. I am gaining knowledge to service my own autos, equipment, boat, and things around the house. I am nearing 50 so really just for my own personal quest.I ordered an EEVblow Bryman 235 after watching some of Dave's reviews on meters which were incredibly informative. It appears I need to get a clamp current meter for things like starter motors in cars and boats etc. What is the best solution as a companion to this meter. I have thought about just picking up a dedicated clamp meter. If not what plugs into this Bryman and will work for me? I need a decent quality solution, but and not a pro that needs a $500 unit. I'd like to keep it around $100. I am in the US. Thank you.As a side note I know many of you are Aussies. I have spent a little time there, have some friends there and love the place! Thank you!

author: Johncanfield
author_rank: Regular Contributor
timestamp: January 29, 2017, 10:03:53 pm
content: Absolutely, get a clamp ammeter! You can get a decent one for under $100, also some will measure DC current but their accuracy isn't that good under say 10 amps. Have a look around Amazon.

author: rstofer
author_rank: Super Contributor
timestamp: January 29, 2017, 10:31:07 pm
content: You can buy a separate clamp-on ammeter at Home Depot or Lowe's. These are specifically intended for electrical work (as opposed to electronics) and most have some kind of DMM functionality. Leave your high quality EEVblog meter on your bench.https://www.lowes.com/pd/Southwire-Digital-Clamp-Meter/50125833Or anything similar.Some of these ammeters will measure DC, most won't.http://www.autospeed.com/cms/article.html?&title=Current-Clamps&A=111656I would buy a 1000A to 50 mV shunt resistor that I could wire in series with the starter and simply measure the voltage drop (the 50 mV full scale part) if I was really interested in starter motors. From my experience, it is either defective bearings (armature dragging) or a defective battery. Usually the battery...The shunt could be like this but I would look for something less expensive:http://www.evwest.com/catalog/product_info.php?products_id=112You would need to come up with some kind of battery -> shunt -> battery cable jumper but that should be pretty easy.I wouldn't object to using my high quality EEVblog meter to measure the 50 mV but I'm not sure that kind of accuracy is required. There might be a place for a less capable and less costly meter.
Totalizer / Hi Speed counter ?? - Page 1
Forum section: electronics / beginners

author: Phaedo
author_rank: Contributor
timestamp: January 22, 2020, 07:07:40 pm
content: Hi,For the purpose of study, I am building a QEI jig with an STM32F103 uC. I have a small motor with a built in hall effect encoder,which I tested with a scope.It gives a quadrature output at about 600 uS for one cycle (rising edge to rising edge).Is there any low cost piece of equipment which can be used to compare my uC result with ? Basically,I would like to see the total accumulated counts.I was quite surprised to find nothing on Aliexpress.
Touch pad for ESP32 ESP32-D0WD touch sensor - Page 1
Forum section: electronics / beginners

author: Watth
author_rank: Frequent Contributor
timestamp: February 17, 2025, 02:17:06 pm
content: Hello EEVblog folks!I am looking into making a touch pad for an ESP32-D0WD on a PCB.From what I understand, a simple copper zone can do the trick. But I still have questions:Are there dimensions restrictions (min or max)? Are there issues with ground plane on the opposite side?Are external components needed?Does the pad nee to be conductive, or not (for example covered by solder mask and/or silkscreen) ?How does the touchpad influence/limit the pin's behavior as a GPIO (if not used as a touch sensor)?Thanks for reading!

author: PGPG
author_rank: Frequent Contributor
timestamp: February 17, 2025, 08:44:31 pm
content: I believe if some IC offers touch pad sensing than there have to be AppNote describing it in detail.

author: Watth
author_rank: Frequent Contributor
timestamp: February 18, 2025, 10:46:41 am
content: You are right, I should have explored this more.FYI, I found this:https://docs.espressif.com/projects/esp-hardware-design-guidelines/en/latest/esp32/pcb-layout-design.html#touch-sensor

author: xvr
author_rank: Frequent Contributor
timestamp: February 18, 2025, 11:07:37 am
content: More info:https://github.com/espressif/esp-iot-solution/blob/release/v1.0/documents/touch_pad_solution/touch_sensor_design_en.mdhttps://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/cap_touch_sens.html

author: Watth
author_rank: Frequent Contributor
timestamp: February 18, 2025, 01:20:45 pm
content: Hey xvr,In the meantime, I found the first link you provided, I was about to update my latest reply!As for the second link, it is about the software part, but I'll keep it in my bookmarks.
Touch panel - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: September 30, 2014, 12:51:22 pm
content: were can you buy a tablet sized capacitive touch panel 7in or 10in with a HID USB controller?

author: sacherjj
author_rank: Frequent Contributor
timestamp: September 30, 2014, 01:53:46 pm
content: Quote from: abdullahseba on September 30, 2014, 12:51:22 pmMost common capacitive TPs in typical tablet formats have an I2C data output from the panel chipset. I've only seen TPs integrated with an LCD with custom USB connections for USB touch monitors.

author: Ton
author_rank: Regular Contributor
timestamp: September 30, 2014, 09:19:31 pm
content: Hi abdullahsebaYou could try Arrow embeddedhttp://www.arroweurope.com/.I got some displays and capacitive touch in 7" from them for prototyping a machine HMI, I don’t know about low volume, but I got 3 pcs as initial samples for the design phase.the touch driver board can be ordered with USB or I2C interfaceand the touch driver is compatible with linux 2.6 kerneljust checked the website, and they have 155 items identified as touch screen - so it might be worth to give them a call, might not be cheap thoughbr Ton

author: IconicPCB
author_rank: Super Contributor
timestamp: September 30, 2014, 09:51:06 pm
content: Olimex from Bulgaria have the young maiden's dream.EDIT: in both a seven inch and a ten inch variant
touch screen - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 09, 2014, 11:00:22 am
content: is there a cheep 5in touch screen colour lcd with hdmi or rca input for £30 max

author: Sam__
author_rank: Regular Contributor
timestamp: March 09, 2014, 11:45:46 am
content: What do you class as cheap?

author: Psi
author_rank: Super Contributor
timestamp: March 09, 2014, 12:55:19 pm
content: Can it be bigger than 5" ?You can get bare board 7" touchscreen lcd with VGA/hdmi/RCA input for US$63http://www.aliexpress.com/item/Diy-Monitor-for-Raspberry-Pi-Lcd-Driver-7-inch-AT070TN94-Touch-Screen-HDMI-VGA-2AV/1520050600.htmlI have never bought one so have no idea how good they are.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 09, 2014, 05:00:08 pm
content: Quote from: Psi on March 09, 2014, 12:55:19 pmIt's brilliant thanks.
Touch sensor experimenting - Page 1
Forum section: electronics / beginners

author: Simon
author_rank: Unknown
timestamp: August 01, 2016, 10:50:09 am
content: Having considered using a light sensor as a tactile pickup I've got a bit more ambitious and I'm thinking of an actual capacitive touch pad. I have found the following controller chiphttp://www.farnell.com/datasheets/1714150.pdf?_ga=1.120898063.646536181.1456469885which hopefully would make life a lot simpler than trying to do all the controls myself. There are no suggestions on the actual footprint of the pad. Does anybody have any clues as to what works best? I'm also wondering how to estimate the capacitance of my pads so that I don't have to have many trials. I suppose I should look out some copper clad board and just do some cut marks to define my pads and see what happens.

author: chris_leyson
author_rank: Super Contributor
timestamp: August 01, 2016, 11:33:20 am
content: Atmels Qtouch sensors are based on the Qprox touch sensor from back in the day. I think I used a 5x10mm touch pad with a Qprox sensor in one design and the sampling cap might have been 10nF, sensitivity can be set by changing the value of the sampling cap.

author: ludzinc
author_rank: Unknown
timestamp: August 01, 2016, 12:01:03 pm
content: Microchip have some excellent application notes. Sorry - not at desk at the moment so can't provide links.

author: Koen
author_rank: Frequent Contributor
timestamp: August 01, 2016, 12:07:06 pm
content: Atmel buttons, sliders and wheels sensor design guide

author: ludzinc
author_rank: Unknown
timestamp: August 01, 2016, 12:26:34 pm
content: Quote from: Koen on August 01, 2016, 12:07:06 pmThat's really good!
Touch sensor - Page 1
Forum section: electronics / beginners

author: akis
author_rank: Frequent Contributor
timestamp: October 05, 2014, 04:29:01 pm
content: I have never used a touch sensor before, I want to use it as an on-off switch, I will connect it to the analog or digital input of a PIC so as long as I can detect a change in voltage that is all I need. I am not sure how touch sensors work, but looking on ebay they appear to be much more complicated than a simple on/off switch. Can someone please help?

author: electr_peter
author_rank: Unknown
timestamp: October 05, 2014, 04:38:52 pm
content: You can find simple touch sensor modules on eBay.http://www.ebay.com/itm/1pc-Switch-Digital-Touch-TTP223-Capacitive-Touch-Sensor-Module-For-Arduino-/351093750132?pt=AU_Gadgets&hash=item51bed17974"Switch Digital Touch TTP223 Capacitive Touch Sensor"These can be configured via two pins to be either alternating on/off (think them to be a latched switch) or momentary switch. I tried those, they have some autocalibration built-in.If you would like to roll your own capacitive touch, try reading app notes of TI MSP430 captouch capabilities.

author: akis
author_rank: Frequent Contributor
timestamp: October 05, 2014, 05:03:52 pm
content: I have read it now : I apply power to it, and when someone touches it, it goes high, 0.8V, and after 12 secs it goes low to 0.3V. I can then compare this voltage with an op-amp or the analog input of a PIC. Am I right or am I missing something ?

author: electr_peter
author_rank: Unknown
timestamp: October 05, 2014, 05:12:51 pm
content: Quote from: akis on October 05, 2014, 05:03:52 pmI am not sure about information source you read, but particular module on eBay outputs close to VDD/VEE (because it has some transistor buffer stage).Previously mentioned TTP223 module outputs logic high or low at voltages close to full VDD(positive rail) and VEE(ground). Just apply power to this module and connect output from this module to digital input of MCU. It should do.If it doesn't work, check voltage levels on the output.TTP223 has 4 operating modes, set by two jumpers (solder bridges) right on the board. One jumper sets latched/momentary operation, other selects default output state (either high or low).

author: akis
author_rank: Frequent Contributor
timestamp: October 05, 2014, 06:25:37 pm
content: I read the same but, originally, misunderstood the specs...http://www.ebay.co.uk/itm/400624301894?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AITThanks for the help, I have ordered two of these
TP cable interference test - Page 1
Forum section: electronics / beginners

author: Spekkio
author_rank: Regular Contributor
timestamp: July 30, 2012, 10:30:00 am
content: Hi!I have a TP cable for CAN, I want to test how sensitive it is to interference.Someone said you can use a relay that shuts on and off, I guess the inductor in the relay would generate noise for interference.Can I do this by putting a square wave through a inductor, or something more simple?What is the best way to test if a cable is good enough, not too sensitive for interference ?

author: Psi
author_rank: Super Contributor
timestamp: July 30, 2012, 10:33:30 am
content: What they most likely meant was to wire the relay so the power to the coil goes through one of the normally connected contacts.So as soon as it turns on it cuts its own power.It will buzz like crazy and the arcing will produce some noise, however the frequency spread and amount of noise it procures will vary wildly. It's by no means a scientific testQuote from: Spekkio on July 30, 2012, 10:30:00 amI'm sure there's super expensive test equipment for this, but 'try and see' is probably the easiest approach.
TP4056 module Blue standby led - Page 1
Forum section: electronics / beginners

author: freda
author_rank: Regular Contributor
timestamp: January 16, 2024, 01:25:23 am
content: My guess is there is no real need for the standby led in a permanent installation.do people just desolder the led, otherwise it eventually drains the battery.is there a proper english translation of TP4056 datasheet?

author: Kim Christensen
author_rank: Super Contributor
timestamp: January 16, 2024, 01:36:38 am
content: The "Greed" LEDumm... The green LED is only on when 5V is applied and the battery has reached full charge. When the 5V charging voltage source is removed (Vin too low), both LEDs are extinguished. So no need to remove any LEDs.

author: freda
author_rank: Regular Contributor
timestamp: January 16, 2024, 02:00:26 am
content: I have blue and red led.the red is working ok,charging, then extinguishesmaybe there is something wrong with it....or my assumptions about putting 2 in series,+....- -|>- +....-^schlocky diode.btw only the bottom one has the DW01? switch (battery protection)

author: freda
author_rank: Regular Contributor
timestamp: January 16, 2024, 02:09:53 am
content: oh! der!!on the battery side the center of 2 batteries in series, the 0V rail of the first module has -|>- connected to the +Vin of the second rail, so the +Vin of 2nd module always has voltage......so that led stays on.yet it seems to charge properly (I think!), both bats in series stop charging within 10-12mv of each other.
TP4056 reverse polarity protection - Page 1
Forum section: electronics / beginners

author: ockrzr
author_rank: Newbie
timestamp: May 25, 2020, 04:48:55 pm
content: Hi folks,I am pretty new to all of this and have drawn up my first schematic. Honestly, I have only combined bits that I found online and am trying to figure out if I made any mistakes before sending it to the manufacturer.What I am trying to achieve is to save the board when - and I definitely will at some point - insert the battery the wrong way around. Sadly, I don't know much about the individual electronic components and I am just learning as I go along. I hope that one of you might be able to help me with the attached schematic.Many thanks in advance.
TP4056 - thermal pad - Page 1
Forum section: electronics / beginners

author: papa_lazerous
author_rank: Newbie
timestamp: June 03, 2019, 11:23:34 am
content: HI all,I have been working on a project that I am using a TP4056 to charge a single 18650 cell, and it all works except the TP4056 gets too hot and fails after some time, the reason is I didn't include a thermal pad in Kicad to take the heat away from the die my fault as I designed the board before I had the chip in front of me and used the wrong footprint.Now I am redesigning my board layout and will put a pad below the chip and some vias to get some of the heat away from the chip. I cannot find any information on what I should connect to the pad to electrically. I used a multimeter on continuity and the pad on the bottom of the chip is not connected to any of the pins on the chip. That said I was going to connect it to the GND plane as that is the largest copper fill I have on the board.I would be very appreciative of any advice on this, the link to the datasheet is below. However it leaves allot of information out imhohttps://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf

author: mikerj
author_rank: Super Contributor
timestamp: June 03, 2019, 12:57:40 pm
content: The datasheet states "Available Radiator in 8-Lead SOP Package,the Radiator need connect GND or impending". "Impending" appears to be a bad translation, and might have meant "isolated" but it seems pretty clear that the pad can be safely connected to ground.

author: papa_lazerous
author_rank: Newbie
timestamp: June 03, 2019, 01:40:27 pm
content: Thanks I will connect it to GND, a second set of eyes definitely helped as I looked over the datasheet multiple times and glossed right over that bit
TPA3110 - Pop Noise - Page 1
Forum section: electronics / beginners

author: almamater
author_rank: Regular Contributor
timestamp: March 03, 2020, 11:30:56 am
content: Hello and sorry for asking.. but i am making one DIY Audio circuit with this ebay board: TPA3110The Problem: When i connect the 12V power supply the speaker makes the 'pop' sound :\YouTubeI tried connect the MUTE Pins at power up and the POP Sound wont occurs, but when i remove the Mute Jumper the POP sound appears immediately..There is any way to avoid this behavior ? Is any simple schematic\circuit with an Transistor\Mosfet to make a small delay at the beginning between Speaker - or + to the Amp + or - ?Thank you.

author: Zero999
author_rank: Super Contributor
timestamp: March 03, 2020, 11:49:22 am
content: According to the data sheet, the TPA3110 doesn't have a proper mute pin. It has a shutdown pin, which puts the output in a high impedance state and draws minimal power. Presumably the shutdown pin also switches off the internal biasing currents, so it doesn't surprise me it cause a pop, when it switches back on again. No mention of avoiding pops at power on is made, in the data sheet, only at power off.http://www.ti.com/lit/ds/symlink/tpa3110d2.pdfThe only thing which will work is a relay connected to each speaker. Timer relays can be purchased, which delay turning on for a second, if you don't want to build anything.

author: Ground_Loop
author_rank: Frequent Contributor
timestamp: March 03, 2020, 12:18:06 pm
content: Apply power through a proper switch instead of just the output of the power supply and put a small cap across the switch contacts.

author: almamater
author_rank: Regular Contributor
timestamp: March 28, 2020, 11:29:57 am
content: Quote from: Zero999 on March 03, 2020, 11:49:22 amHello again, i solved the POP Noise problem using onerelayat each speaker with one timer circuit (555) that makes one delay (~2 seconds) at startup. Thanks.Now i have another questionI am using one100K AudioPotentiometerfor volume control, like this:I noticed that one speaker is a litle louder than the other, for example, if the potentiometer its at lower position (both speakers are OFF) and if i start to rotate it a litle, one speaker (right) starts first than the other (left)..This happens because the potentiometer does not have the same resistance for both outputs?! Can i solve this by putting one resistor between the In and Out pins (Midle and Right pin of the potentiometer)?

author: fcb
author_rank: Super Contributor
timestamp: March 28, 2020, 11:52:33 am
content: That's to do with manufacturing tolerances - tracks are not identical in taper towards one end. Very common.You'd need to move-up to a trick audio potentiometer (like the ALPS Velvet series) to find one that minimises it. If you slug one end of each channel with a resistor then you'll get some relief, but at the expense of pot range an taper curve.
TPMS based project - Page 1
Forum section: electronics / beginners

author: FLIP
author_rank: Contributor
timestamp: November 10, 2013, 11:03:41 am
content: after coming across this and doing some reading and investigatinghttps://github.com/jboone/tpmsa few people have advised me that their cars here in Australia have a TPMSso i was wonderinga) if it would still work hereb) using the same set up, but maybe a differ .py scriptwhat else could be acheivedthanks
TPS61040 max output current - Page 1
Forum section: electronics / beginners

author: mrmp17
author_rank: Contributor
timestamp: March 30, 2014, 12:26:08 pm
content: Hi!What would be max current from tps61040 boost converter, if boosting from 5V to 10V?datasheet:http://www.ti.com/lit/ds/slvs413f/slvs413f.pdf
TPS62160 buck controller problem - Page 1
Forum section: electronics / beginners

author: mcdesca
author_rank: Contributor
timestamp: November 07, 2015, 08:38:26 am
content: Dear everybody,I was just trying to upgrade my library with a new low-power buck converter, that could switch up to a few MHz in order to save space and reduce ripple in my designs.I had a go with the TPS62160.In the problematic project, the design included two of them: 12V(external PSU) to 5V and another 5V to 3V3 downstream.The 3V3 worked flawlessly and was able to surge 1A constant current with no problems. So did the 5V until I started with the external PSU power up-down cyclic test. The 3V3 worked perfectly (I guess, since it is downstream to the 5V, it had better filtering of the spikes already), the 5V though, had given up after a couple of cycles.I had the oscilloscope connected and the trigger set at 15V at all times, with no capture to be seen. Even though the varistor+TVS+LC filter is always to be included in my designs, I expected to work without it since my Manson PSU has a relative good signal quality.I cannot help thinking, that it has to be a spike over the 17V max volts the chip can witherstand. I have already decided myself for the LMR14206 (I accept recommendations here, something in the MHz range, 3-30Vin, 0,8A...) but I keep wondering what the real cause was and how it could be avoided in other designs.Many thanks for your time.Best,