hybridfree/eevblog-posts huggingface dataset:
Chip Identification - Page 1
Forum section: electronics / beginners

author: dgrz
author_rank: Newbie
timestamp: May 07, 2022, 02:15:23 am
content: Hi everyone,I'm trying to repair a windlass remote control for my boat. One of the screw gaskets were missing (from the factory) and it died when I had a splash of salt water on it. I left it for quite a while before attempting to do a repair and one of the ICs has a connector that simply had corroded away. Seems to be some sort of transistor, but I can't find anything like it. The rest of the board looks good after some cleaning and reflowing, so I'm hopeful!I'm trying to identify this IC, marked with pins T B and Y.Does anyone have a clue? Thanks in advance!

author: tooki
author_rank: Super Contributor
timestamp: May 08, 2022, 03:43:44 pm
content: None of the pins seem to be missing?I found two chips that match the marking (a MOSFET from Renesas and a voltage regulator from Torex semiconductor), but neither pinout would make sense in the circuit in the photo. :/Can’t you share more of the board for context? (And the model number of the remote, etc.) More info = better chances. Secrecy is not a virtue.P.S. “chip” = shorthand for “microchip” = integrated circuit = multiple transistors (and sometimes other things) combined into a circuit on single piece of silicon (so a single transistor is, by definition, not an IC)

author: gamalot
author_rank: Super Contributor
timestamp: May 08, 2022, 04:12:28 pm
content: NTJD1155Lhttps://www.onsemi.com/pdf/datasheet/ntjd1155l-d.pdf

author: dgrz
author_rank: Newbie
timestamp: May 09, 2022, 02:40:06 am
content: Wow, thank you so much!

author: dgrz
author_rank: Newbie
timestamp: May 09, 2022, 02:51:06 am
content: Quote from: tooki on May 08, 2022, 03:43:44 pmThis is a photo of a second (and working) remote that I have!QuoteThanks for looking into it and I should have shared the details right away. Gamalot figured it out, I think, but for completeness - here's the exact model:https://www.sleipnergroup.com/thruster-systems/remote-controls/Fjernkontrollsender-baugvinsjQuoteThanks, will be more precise next time!Next challenge is to find a pin-compatible replacement for the NTJD1155L.

author: dgrz
author_rank: Newbie
timestamp: May 20, 2022, 07:27:35 am
content: Was able to get some NTJD1155Ls that just came back into stock and it worked perfectly. Thanks again for your help gamalot and tooki!
Chip identification - Page 1
Forum section: electronics / beginners

author: ChristopherN
author_rank: Unknown
timestamp: July 14, 2017, 01:19:02 pm
content: Hi,it got 25 of those QFNs as part of a shipment labeled wrong. Can anyone identify those?ThanksChristopher

author: Yansi
author_rank: Super Contributor
timestamp: July 14, 2017, 02:44:01 pm
content: http://www.ti.com/lit/ds/symlink/tps62090.pdf10 seconds on google(Just googled for "QFN16 SBX". The "TI" on the package stands for the obvious.)You can verify the identification is correct for example by measuring pins 1 and 2, if they are shorted, most likely it is the correct part number. Same for PVIN pins 11, 12.

author: ChristopherN
author_rank: Unknown
timestamp: July 14, 2017, 02:50:21 pm
content: Great, thanks!It somehow never came to my mind to include the package in my search

author: Yansi
author_rank: Super Contributor
timestamp: July 14, 2017, 02:55:42 pm
content: That helps always a lot!

author: ChristopherN
author_rank: Unknown
timestamp: July 14, 2017, 03:05:44 pm
content: I have no use for the parts, so I'm giving them away for free:https://www.eevblog.com/forum/buysellwanted/giveaway-25x-ti-tps62091rgt*/
Chip Identification for a Newbie - Page 1
Forum section: electronics / beginners

author: ddctechguy
author_rank: Newbie
timestamp: June 24, 2015, 01:16:56 am
content: Hi, I am new to the forum, as well as new to the "modern day" electronics scene. I am currently trying to repair 2 devices, however, not working with electronic circuits since 1988, I am having a very hard time recalling how to look up chip replacements and equivelents. Would someone here be willing to take a look at three chips I need and tell me what the heck they cross reference with? I have searched and googled for endless hours, but without the proper working knowledge of modern day chip markings I seem to be just spinning my wheels.Thanks in advance for any help.Lee C.

author: Mr.B
author_rank: Unknown
timestamp: June 24, 2015, 01:25:05 am
content: Welcome to the forum.Perhaps you could use Google.The following search terms get almost direct hits on the datasheets.Texas Instruments VN12Texas Instruments 75176bTexas Instruments LVC541AEdit: All appear to be in stock at Mouser.

author: kolonelkadat
author_rank: Regular Contributor
timestamp: June 24, 2015, 01:33:09 am
content: this website will make you go crosseyed, but it is super useful when trying to identify manufacturer logohttp://www.classiccmp.org/rtellason/logos/semiconductorlogos.html

author: ddctechguy
author_rank: Newbie
timestamp: June 24, 2015, 02:36:50 am
content: Thank you both for your speedy response!!!! I now have the parts on the way from Mouser.Lee C.
Chip identification help - FOUND Silicon Labs EFM8 BB1 - Page 1
Forum section: electronics / beginners

author: LaurentR
author_rank: Frequent Contributor
timestamp: April 08, 2017, 08:07:47 pm
content: As part of my quest to reverse engineer the Nanoleaf Aurora system:https://www.eevblog.com/forum/projects/nanoleaf-aurora-teardown/msg1158410/I am trying to ID this chip, which is in the tiles. I assume it is some kind of microcontroller as it chats with the wifi board using a number of serial message types and it drives WS2812 LEDs in the tile.Markings:BB10F4G?JG3 (yes, I blew the chip - that's what happens when you play with a board with VDD=24V and you're not careful...)1636 A

author: LaurentR
author_rank: Frequent Contributor
timestamp: April 08, 2017, 08:19:52 pm
content: Well ok, somehow I missed it the first time I googled it.It is a Silicon Labs EFM8 "Busy Bee" BB1 in a QFN20 packageC8051 inside with a UART (makes sense given the serial protocol)http://www.silabs.com/products/mcu/8-bit/efm8-busy-bee/device.efm8bb10f4g-qfn20
Chip Model and Manufacturer Identification - Page 1
Forum section: electronics / beginners

author: DrLov
author_rank: Newbie
timestamp: March 02, 2022, 01:09:08 am
content: I need help identifying these chips. They are part of a Drone receiver. Kindly, I ask, thank you!

author: free_electron
author_rank: Super Contributor
timestamp: March 02, 2022, 03:52:25 am
content: looks like some rf stuff. two baseband processor , bunch of filters / amplifier stuff...a lot of those things have been borged by Qorvo

author: DrLov
author_rank: Newbie
timestamp: March 02, 2022, 04:19:42 am
content: Yes, some look like amplifiers. I'm trying to identify a signal problem at the 2.4ghz frequency of this card, so I want to understand all the components. The others have already been identified. Can you help me with something else?

author: amyk
author_rank: Super Contributor
timestamp: March 03, 2022, 01:55:39 am
content: One of them is aTR8024but there's very little information on it besides one guy who worked at the company claiming it could be compatible with a Skyworks part.

author: free_electron
author_rank: Super Contributor
timestamp: March 03, 2022, 02:09:03 am
content: a lot of that stuff is under NDA... chances of finding documentation are nil.

author: DrLov
author_rank: Newbie
timestamp: March 03, 2022, 02:41:29 am
content: Do you have something about the IE1000? I would like to know the function of this IC. I'm trying to repair a circuit that is faulty at 2.4ghz frequency, so I'm trying to identify the function of each Chip. Some I already know the function...I'm grateful for all the help. Thank you!

author: DrLov
author_rank: Newbie
timestamp: March 03, 2022, 11:21:40 pm
content: If someone could help me discover the model and manufacturer of this "78X" chip, it would help me a lot. Thank you!
Chip on Board how is it low cost?? - Page 1
Forum section: electronics / beginners

author: rakeshm55
author_rank: Regular Contributor
timestamp: December 02, 2018, 05:48:51 am
content: How can Chip-on-Board lower costs of production?? Why do use and throw products prefer Chip-On-Board??https://learn.sparkfun.com/tutorials/how-chip-on-boards-are-made/allI was going thru the above link . My primary understanding was chip on board offer dead cheap manufacturing process. But it looks like during manufacture chip board undergo many different process. How is it cost effective than using a single uC chipset and wave soldering ?? no separate process neededMy assumption is that chip on boards are pre-programmed controllers.Please educate

author: amyk
author_rank: Super Contributor
timestamp: December 02, 2018, 06:37:41 am
content: The cost of the packaging itself becomes significant in high-volume applications.

author: ataradov
author_rank: Super Contributor
timestamp: December 02, 2018, 06:57:06 am
content: Yep. Event the cost difference between WLCSP and BGA or QFN is significant in large quantities. It may be 1/3 of the cost of the whole device.I don't think there is a huge cost difference between WLCSP and COB, but I imagine board cost is higher for WLCSP.And most modern device can be programmed in-circuit, so it is not a big deal.

author: Gyro
author_rank: Super Contributor
timestamp: December 02, 2018, 08:27:52 am
content: More discussion...https://www.eevblog.com/forum/chat/chip-on-board/
Chip Quik or Kester Solder paste WTB - Page 1
Forum section: electronics / beginners

author: einhander
author_rank: Contributor
timestamp: May 07, 2025, 07:02:05 am
content: hi guys, I have about 6-7 Sony PSPs where the ribbon connector for the LCD screen no longer locks into place.I was wondering what members here thought of what brand/model of Solder Paste I should buy to use my hot air station to get a new connector back on the PCB.chat soon

author: jwet
author_rank: Frequent Contributor
timestamp: May 07, 2025, 03:53:20 pm
content: Chipquik is good stuff and available consistently. They have specialty solder for rework with a lower melting temp that is really cool. I really like their thick flux. Kester is the premier brand and its all very good- a little pricier but not bad. The standard Amazon stuff is usually not bad, especially if you're using a stencil and hot air, not as consistent in a profiling oven- inconsistent. They only problems I've ever really had is using really old crusty stuff and I have gotten pretty old stuff from some vendors. Other reputable guys are Hakko, MG and SRA. Good luck.

author: thm_w
author_rank: Super Contributor
timestamp: May 08, 2025, 01:11:04 am
content: Photo? If its just a broken clip maybe the clip alone can be replaced.https://www.reddit.com/r/PSP/comments/8qge3o/broke_a_ribbon_cable_clamp_any_way_to_fix_it/https://www.reddit.com/r/PSP/comments/173o3l1/broke_my_ribbon_cable_clip/
Chip Quik Silicone - Page 1
Forum section: electronics / beginners

author: IvoS
author_rank: Frequent Contributor
timestamp: February 07, 2023, 08:43:16 pm
content: I have thishttp://www.mateksys.com/?portfolio=elrs-r242.4GHz receiver with 2 IPEX MHF 1 antennas plugged into that. I want to use electronic grade silicone to secure both antennas to PCB, so they don't separate in mid air. Would this silicone be suitable?https://www.chipquik.com/store/product_info.php?products_id=492011Is it OK to cover all surface area including those input capacitors and partially the amplifier chip? Thanks.

author: jpanhalt
author_rank: Super Contributor
timestamp: February 08, 2023, 12:21:44 am
content: Why do you want something that is black and has TiO2 in it?

author: coppercone2
author_rank: Super Contributor
timestamp: February 08, 2023, 12:28:51 am
content: I suggest you use some zip ties. That uFL connector wont disconnect if its new. If you use it a whole bunch of times (like 30 times) then its a risk.I don't recommend putting goo on circuits in general. Maybe a tiny dab on top of the coaxial cable near the PCB after its zip tied down, making sure to lay it so that you can slip a blade under it easily if you need to replace the antenna because of cable or antenna damage. You can trust a zip tie way more then adhesive IMO.The number of delaminated things I found vs the # of zip ties I found broke (and I have ANCIENT stuff) puts the favor WAY towards the zip tie. The only zip ties I ever found broke were the super crappy ultra skimpy ones that look like a rope ladder, and that was at least 30 years old and exposed to sun. And you can get some really nice zip ties from panduit or something.And if you put a heat shrink over the entire PCB with a zip tie, you can cut it off if there is some kind of RF problem (unlikely from a thin piece of heat shrink). And you can then put a tiny dollop of silicone in the middle of the underside of the PCB on top of the heat shrink before you zip tie it down for extra protection.
Chip SL490 functionality alternative? - Page 1
Forum section: electronics / beginners

author: FriedMule
author_rank: Frequent Contributor
timestamp: October 05, 2020, 02:16:52 pm
content: HiI am looking for a "remote control" chip with the same functionality as the SL490 chip. It determines the pushed button by a "grid" like pattern, see picture.I am only looking for a remote control chip with that grid functionality, number of legs, smd/tht, size or anything is not important since I am hoping to use the chip on a new project.I have found these alternatives but all of them are no longer in production.SL490UAA4000NTE1755SK10038

author: DrG
author_rank: Super Contributor
timestamp: October 05, 2020, 02:38:06 pm
content: I wonder if those chips have not given way to programming controllers, which can provide those functions...e.g.,http://www.avr-asm-tutorial.net/avr_en/ir/ir_tx/ir_tx.html

author: FriedMule
author_rank: Frequent Contributor
timestamp: October 05, 2020, 03:36:28 pm
content: Hmm yes that may be, I do also think an adorino may be a solution, I am just trying to avoid coding and to complicated solutions.How would you make a TV/Stereo system remote control, with maybe a hardware chip?
Chip to select output based on pulses - Page 1
Forum section: electronics / beginners

author: Stonent
author_rank: Super Contributor
timestamp: August 03, 2014, 06:45:55 am
content: I thought about a need for a chip in my time machine project that would switch a route based on pulses. I don't know what I would call it so I don't know how I could google it.I'm looking for a chip that's the equivalent to a SP8T switch. So every time you send a pulse to the chip, it would advance to the next throw on the switch.My idea was for addressing several 7 segment displays by sending a pulse each time I had finished pushing the output to it via a 74hc595 to change to the next cathode. So the anode would be controlled by the 595 and the cathode would be controlled by this unknown chip. Is there a name for this kind of chip?I know I could use a 3 to 8 decoder for switching to multiple 7 segment displays but I'd like to do it with 1 pin, preferably the unused 8th bit on the 595.What do you think? Right now I'm too far along to change my plans but I would like to know if there's a name for this type of chip for future reference.

author: Simon
author_rank: Unknown
timestamp: August 03, 2014, 06:49:12 am
content: Time machine did you say ? Pray do tell.Sounds like you need a counter driving your demultiplexer (the 3 to 8 thing you mention). You pulse the counter, that counts up the addresses of you demultiplexer that will wuth each count change output in order, you just tie the demultiplexer input to VCC.

author: arcom
author_rank: Contributor
timestamp: August 03, 2014, 09:06:33 am
content: A 4017 decade counter will do what you want. I have used it in the past for 7-seg. displays but you need additional transistors to switch on the segments.

author: rob77
author_rank: Super Contributor
timestamp: August 03, 2014, 09:20:43 am
content: Quote from: arcom on August 03, 2014, 09:06:33 am+14017 (decade) and 4022 (octal)you can think of a 4022 as a 3bit counter + 3 to 8 decoder in one package , and 4017 is similar but counts to 10 and has 10 outputs.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 03, 2014, 11:06:16 am
content: In the past, I just used an additional IO port. But on that thing, IO ports weren't just pins on an MCU, I could chuck in another latch and decoder and put in as many ports as I wanted...http://seventransistorlabs.com/tmoranwms/Elec_Z80.htmlIf you're running from an MCU, and don't have enough pins for the individual column selects, a decoder is good (three pins). A counter-decoder and two pins (one clock, one reset -- make sure to reset it every cycle so it doesn't skip off into la-la land) saves you one more. At that point, you'd be better off looking at the row drivers as well (e.g., a '595 driven by SPI -- now you're down to three and two pins, well within an 8 bit port).Tim
Chip with "HGFP" marking - Page 1
Forum section: electronics / beginners

author: HighDesert
author_rank: Newbie
timestamp: January 17, 2024, 02:38:33 am
content: HelloI'm trying to reverse engineer a voltage converter that is no longer available and I've come across this chip. A SOT-23-5 package with a marking "HGFP". Has anyone seen this before? I a quick google search leads me to believe it's made by Microchip but I haven't confirmed it. Any help is appreciated!

author: DavidAlfa
author_rank: Super Contributor
timestamp: January 18, 2024, 03:43:44 am
content: https://smd.yooneed.one/http://www.smdmark.com/en-UShttp://www.marsport.org.uk/smd/mainframe.htmAlso check smd codes data book:link
Chipquik Flux - Characteristics - Page 1
Forum section: electronics / beginners

author: 2X
author_rank: Frequent Contributor
timestamp: July 24, 2025, 03:58:37 pm
content: Hi,In some chipquik flux datasheets I see on the specs "Excellent wetting" & "Soldering flip chip components" & "Long stencil life" & "Wide process window". What these terms means?1) Excellent wetting2) Soldering flip chip components3) Long stencil life4) Wide process windowSMD491-10M (by the way this flux smells very bad)https://www.chipquik.com/datasheets/SMD491-10M.pdfNC551-10CC (this is my favorite for hand soldering)https://gr.mouser.com/datasheet/2/73/NC551_10CC-2511402.pdfSMD291 (this is very good for hot air soldering)https://gr.mouser.com/datasheet/2/73/SMD291-746165.pdf

author: thm_w
author_rank: Super Contributor
timestamp: July 25, 2025, 12:05:29 am
content: Wettings is basically how well it spreads and bondshttps://kaisertech.co.uk/content/soldering-wetting-what-is-it-why-is-wetting-so-importantFlip chip components need no clean low residue flux:https://documents.indium.com/qdynamo/download.php?docid=3109Long stencil life is more for solder paste, how long it can sit in the open and still be usable, you can see the hour rating at the bottom. For flux after a while it will start to dry and become too thick.Wide process window is them saying it has a large temperature range that its rated to work for.If you haven't seen these comparison videos:https://www.eevblog.com/forum/other-blog-specific/nanofix-youtube-flux-comparison/https://www.youtube.com/watch?v=iKDAmY9Rdag

author: tooki
author_rank: Super Contributor
timestamp: July 25, 2025, 10:29:22 am
content: Quote from: 2X on July 24, 2025, 03:58:37 pmThese two are the same product, just in a different style of syringe.I’ve tested that flux, and I don’t know what you mean about the smell — the flux itself doesn’t smell at all, and the fumes when heated smell like toasted hazelnuts, rather than the acrid smoke many fluxes produce. The “lead free” version (SMD291NL) is my everyday flux, though I’ll probably order SMD291 next time, since I mostly work with leaded solder.

author: 2X
author_rank: Frequent Contributor
timestamp: July 25, 2025, 06:30:28 pm
content: Quote from: tooki on July 25, 2025, 10:29:22 amI mean the SMD491-10M (I apologise... I made a mistake and post two times the SMD291).Also, an everyday flux for the last months where I am very very satisfied (it smells a bit more of the NC551-10CC) is the "[bTF-SV3-A10-K"TF-SV3-A10-K:https://stirri.eu/products/stirri-v3-tf?variant=47807937315133If you want give a try also to NC551-10CC (I have tried the "SMD291NL" after an old recommendation of you and it is very good for lead free solder) and TF-SV3-A10-K.In my expirience the NC551-10CC is better from the SMD291.
Chipquik No Clean Tack Flux - Page 1
Forum section: electronics / beginners

author: Legion
author_rank: Frequent Contributor
timestamp: March 19, 2014, 04:10:54 pm
content: Just got some of this from digikey. Came in an 8cc tube. Never bought flux before. It came in an insulated bag with a cold pack inside. I hadn't heard that flux was temperature sensitive. Should I store it in my fridge?

author: nanofrog
author_rank: Super Contributor
timestamp: March 19, 2014, 05:04:13 pm
content: Yes, if you want the longest shelf-life from it.Chip Quik set the shelf-life @ 1yr in the fridge, 6mo @ room temp.

author: Legion
author_rank: Frequent Contributor
timestamp: March 19, 2014, 05:53:43 pm
content: Quote from: nanofrog on March 19, 2014, 05:04:13 pmThanks!
Choetech Desktop 6 port USB Charger - Page 1
Forum section: electronics / beginners

author: Tulip
author_rank: Newbie
timestamp: August 16, 2015, 07:33:07 am
content: Hi thereI have a Choetech Desktop 6 USB Charger, witch two of the ports are Quick Charge 2.0I was charging my 15000 mAh powerbank, after some time the Quick Charge 2 started to be some unstable (come and go). I did hear something who sounded like coil whine.Then i continue the charge in my regular wall adapter, no problem there. So there is now a problem with the 6 port USB Charger.I later tested the 6 port USB Charger with a usb voltmeter, it can now only deliver about 2-3W instead of 15W.The other Quick Charge port work as normal.So i tear it apart and notice 3 caps that dont look so fresh lolare this typical sign of blown caps or just "glue" brown "gunk"?Them are marked :h-cap 15uf 400v Low esr.I have googled h-cap but not much help.Few pics. and have more if neededThanks

author: SeanB
author_rank: Super Contributor
timestamp: August 16, 2015, 08:21:54 am
content: Other end of the board where the outputs are would be nice. These caps are the input mains side, and are 15uF 400v capacitors, fake ones meant to look like Nippon Chemicon at a first glance, but they probably are still usable. The output side will be the capacitors that need replacing, though if you can change these as well it will not be amiss. The brown is glue, placed there in an attempt to hold them in place.
Choice between two motors. - Page 1
Forum section: electronics / beginners

author: johnmoth
author_rank: Newbie
timestamp: April 07, 2013, 06:03:49 am
content: I am currently at a tossup between getting thishttp://www.pololu.com/catalog/product/2285and thishttp://www.ebay.com/itm/FAULHABER-DC-9V-Motor-1524B009SR-Gear-19-1-Encoder-512CPR-USED-free-ship-/150968781120?pt=LH_DefaultDomain_0&hash=item232670c940The only problem with the first one is that it might need a 90 degree gearbox because they are too long to place next to eachother.On another note, we wanted to reduce the gear ratio cheaply. what would be a good way to do that?

author: Astroplio
author_rank: Regular Contributor
timestamp: April 07, 2013, 09:19:53 am
content: Hi john, welcome to the forumon the first link from Pololu you have the option to select a lower ratio gearbox 34:1 or even lower 9.7:1 to go with the motor(see where it says "select options")If you plan on modifying gear ratios anyway maybe you should check other options, like the Tamiya gearboxes I see on the Pololu site, since they also come in the angle configuration you talk about.You can also find mods from other people on the internet that have added encoders on these gearboxes, if you absolutely need to have an encoder.About reducing the gear ratio cheaply, I don't know any solution to that.I assume you ask about that because you want a better control of the rotational speed, so you need to get a lower ratio gearbox than desired, and play with PWM to reduce further the rot.speed. Also operating DC voltage comes into play with these, if you run the motor on a higher voltage than the specs, then you will get a faster speed (the opposite if you reduce the operating voltage). But I don't recommend using a higher voltage, there is a risk of burning the windings (unknown tolerances... you can experiment if you like of course...)George

author: johnmoth
author_rank: Newbie
timestamp: April 08, 2013, 03:38:13 am
content: Excellent. Thanks!
Choice of Actuators - Page 1
Forum section: electronics / beginners

author: jots123
author_rank: Newbie
timestamp: December 31, 2019, 12:29:51 pm
content: Hi all,Does anyone have any recommendations for an positional feedback linear actuator with an inbuilt potentiometer that is strong enough to lift and support a person (max weight 80kg) on a chair with sufficient factor of safety? (Max load should be about 150kg) Basically, this electrical actuator is to replace the common gas cylinder in height adjustable chairs.I have found some that might work but I have some problems with it..The PA-17 Heavy Duty Actuator by Progressive Automations is capable of lifting very high loads (up to 900kg). However, it draws alot of current (20A @ 12V) and it is very expensive..https://cdn.shopify.com/s/files/1/0061/7735/7891/files/Heavy_Duty_Linear_Actuators_PA-17.pdf?13226Another actuator is the Feedback Rod Linear Actuators by Firgelli Automations which is much cheaper and draws less current (5A @ 12V). However, its max load is only 90kg, which just barely meets the requirement.https://www.firgelliauto.com/collections/feedback-actuators/products/feedback-rod-actuatorI also need the actuator to have a minimum stroke of 13cm (5.2 inches). I have been searching for a suitable one for days.Any recommendations and suggestions will be greatly appreciated! Thanks!
Choice of differential probe (Micsig model's) - Page 1
Forum section: electronics / beginners

author: DisasterNow
author_rank: Regular Contributor
timestamp: December 22, 2023, 09:26:06 pm
content: My initial idea (I asked in another discussion) was to get a 100x passive probe, but then I decided to get a differential probe. The oscilloscope is a Siglent 1204.I wanted your advice on which model to get from the Micsig brand (they seem to be at a good price).The use would be of measurements on the AC and DC voltage that is generated in the input stages of the power supplies (the electrical network is 230AC), therefore Vpk just under 700V.The doubts would also be due to the high attenuation of certain models.DP10007: is 100x attenuation suitable for seeing a signal with a Vpk of 700 v on the full display? Interestingly, it also has 10x attenuation.DP10013: it has no problems with the voltages I should measure, but perhaps it starts from too high an attenuation? (50x).Then there would be the models of the MDP series, where the choice could be between theMDP700, 701, 1500, 1501models.Could you help me make this choice?Thank you

author: bdunham7
author_rank: Super Contributor
timestamp: December 23, 2023, 05:39:10 pm
content: I have the DP10013 and it seems fairly decent for just looking at actual mains power and things directly connected to mains that can't feasibly be isolated. The issues that come up with all of these probes are input impedance and common-mode rejection (CMRR). The DP10007 apparently had/has particularly poor CMRR and somewhat worse input impedance than the DP10013. They were available in the EEVBlog store for a while, but Dave removed them because they didn't meet the CMRR specs. The MDP models look to have even better input impedance, noise and CMRR numbers but they do cost more.Any of these would probably work OK for looking at the large signals in an SMPS, but invariably you start wanting to look at the high-side gate drives and such. This is where the CMRR and input impedance really start to matter and I'd at least avoid the DP10007 if that is your intended use. The MDP700 might be better, but I haven't tried one and they are twice the price of the DP10013. At that price you might consider one of the Sapphire-manufactured models like the EEVBlog HVP70.

author: DisasterNow
author_rank: Regular Contributor
timestamp: December 23, 2023, 07:40:06 pm
content: Quote from: bdunham7 on December 23, 2023, 05:39:10 pmThanks for the reply.So I would rule out the DP10007.But perhaps I could also exclude the MDP 700, I would prefer to stay on the model that does not have the voltage limit around 700v.The DP10013 and MDP1500 models remain; I might stay with the DP model (like yours), because perhaps the price of the MDP is too high.Thanks again for the help.Note:DP10013 costs around 200.00 eu, while MDP1500 costs 260.00 eu. I would almost be willing to get the newer model mdp1500.
Choice of Diode to prevent - Page 1
Forum section: electronics / beginners

author: LoveLaika
author_rank: Frequent Contributor
timestamp: May 12, 2021, 02:31:49 pm
content: I'm running a sim of a trans-impedance amplifier that takes two current sources. I'm modelling my current sources as two exponential currents using the following parameters:EXP(0 -20m 10n 500p 5n 250n)Initial Current = 0 APulsed Current = -20 mARise Tau = 500psFall Delay = 5 nsFall Tau = 250nsThe two sources differ in their activation time by 25 ns, and they both go into a TIA to convert their current sum into a voltage. Straightforward, but I wanted to prevent from current backflow from one source to the other, so I'm thinking of adding a Schottky diode in series with my sources to prevent unwanted backflow, but I can't find a good Schottky diode model that would prevent backflow. What parameters should I look for here?To add more information, while my current source is a simple, ideal one for testing purposes, the actual current source is a photodiode, two of them. Once they 'activate', they generate a voltage of -35 mV at the summing node, passing through the feedback resistor of the TIA to convert the current to a voltage signal. Given how the voltage difference is so tiny, should the diode forward voltage be tiny as well? The lowest forward voltage I found was 140 mV on Digikey.

author: rs20
author_rank: Super Contributor
timestamp: May 12, 2021, 02:38:29 pm
content: Since you seem to be staying firmly planted in the virtual (simulation) world, maybe just use an ideal diode?https://electronics.stackexchange.com/questions/353826/how-to-make-an-ideal-diode-model-in-ltspice

author: LoveLaika
author_rank: Frequent Contributor
timestamp: May 12, 2021, 03:12:20 pm
content: I think I'm not seeing it intuitively. Looking at the wiki's model of the TIA, the current flows into the feedback resistor, which the TIA converts to a negative voltage. Now, like with my sim, if the current flowed into the opposite direction away from the feedback resistor, the output becomes a positive voltage. In order for it to flow in the opposite direction, the voltage at inverting terminal (or summation node) where the source drops with respect to the other end of the current source, connected to ground. So if that's the case, the backflow diode should follow the direction of the current source?https://en.wikipedia.org/wiki/Transimpedance_amplifier

author: LoveLaika
author_rank: Frequent Contributor
timestamp: May 12, 2021, 03:55:39 pm
content: Thanks; sorry, I get what you're getting at now, using the ideal diode model and adjust as needed to see how it works.
Choke differences - Page 1
Forum section: electronics / beginners

author: Momchilo
author_rank: Regular Contributor
timestamp: July 15, 2019, 03:40:45 pm
content: Hi,I look for chokes to smooth the leg currents of a inverter. The inductance should be ~1mH and the maximal current is 5A at 100V.I know that something like this will work:157DBut it's chunky and there are a lot more smaller chokes with similar specifications likethis Kemet one.I could use both coils for the positive and negative leg instead of two big chokes.I don't think I could use the Kemet choke, it's built for another purpose, but why wouldn't it work? I know that the voltage in each leg of the inverter isn't sinusoidal. Because of the PWM control, it's more pulse-shaped. So for a very short time the current is more DC likely. That's the whole reason for this choke to get a sinusoidal current. But is that the problem why I can't use the small choke?Thanks for your help.Best regardsMomchilo

author: MagicSmoker
author_rank: Super Contributor
timestamp: July 15, 2019, 04:08:11 pm
content: The Hammond choke is more suited to the job and is actually a choke (that is, an inductor expected to withstand a significant DC or low-frequency bias), whereas the Kemet part is commonly (at least in English) called a "common mode choke" and is not actually a choke at all, but a 1:1 transformer which cannot support any net DC bias, really. Common mode chokes are expected to be placed in series with the forward and return conductors of a power supply, etc., so that the magnetic flux from any "normal mode" curren (that is, it goes out on one line and comes back on the other) is cancelled out, while common mode current (that is, having the same phase/magnitude on both lines) sees an inductance that is 4x larger than the single winding inductance, providing significant filtering.For your specific application you want a choke that has a laminated silicon steel core with a "large" air gap (large being a relative term here). The Hammond part most likely fits this description, though it may not necessarily be ideal or the most cost-effective for the job.

author: capt bullshot
author_rank: Super Contributor
timestamp: July 15, 2019, 04:09:39 pm
content: The small one is a "common mode choke", used for EMC purposes.These have two windings on the same core. It's usage requires the current through one winding to return through the other winding, so the sum of currents in the core is zero for the normal operating current. The inductance in this mode is near zero.You may find some better explanations here:https://www.we-online.de/web/en/passive_components_custom_magnetics/blog_pbcm/blog_detail_electronics_in_action_61439.phphttps://en.wikipedia.org/wiki/Choke_(electronics)Short conclusion: Common mode chokes don't work for your purpose.
Choose an inductor and capacitor for AOz3103di buck converter - Page 1
Forum section: electronics / beginners

author: nour
author_rank: Frequent Contributor
timestamp: July 27, 2017, 05:25:19 am
content: I want to build a Fixed 5v buck converter with 2.5 Amps output from a 12v input, I will be using AOZ3103DI.I want to select the inductor to be able to handle the output current with minimal output ripple, I have tried to read the datasheet but I am a little bit lost.Link to the datasheethttp://www.aosmd.com/res/data_sheets/aoz3103di.pdf

author: nour
author_rank: Frequent Contributor
timestamp: July 27, 2017, 07:59:29 am
content: I am expecting the load to range from 1-2.5 amp

author: nour
author_rank: Frequent Contributor
timestamp: July 27, 2017, 09:10:42 am
content: Ok that is very good, what about the capacitor, the CC and the CBSTI don't know why don't they give values for the typical application, at least recommend one or two general outputs like 5v or 3.3v?Thanks

author: nour
author_rank: Frequent Contributor
timestamp: July 27, 2017, 09:38:25 am
content: Thanks a lot, I think for the Cout I will go for low ESR 100 or 220uF tantalum cap for 2.5A
Choose PSU that can handle back emf from motors - Page 1
Forum section: electronics / beginners

author: nour
author_rank: Frequent Contributor
timestamp: September 16, 2016, 07:35:01 am
content: I am not sure how to start this question, but I am trying to run 4 stepper motors with from 48V DC source eachIt is Sanyo denki 103 - H7823 - 1741 bipolar motor, the specs as following:Current 4AResistance 0.65RInduction 2.4mHBack E.M.F 75 V/KrpmI want to know how to choose a proper Power supply to handle the motor back emf?I read somewhere that the power supply should be able to handle the back emf so it wouldn't go through the drivers and other electronics!I really do not understand this point, can someone explain how a power supply would or would not be able to handle the motor's emf?

author: Srbel
author_rank: Frequent Contributor
timestamp: September 16, 2016, 09:27:05 am
content: I would just use a flyback diode?

author: Kleinstein
author_rank: Super Contributor
timestamp: September 16, 2016, 09:49:10 am
content: You need free wheeling diodes to direct the current from back EMF to the supply. The usual driver circuits have that. The supply must be able to take up the extra current, that otherwise would raise the voltage too high. Usually just sufficient capacitance at the supply is enough.Usually the main source is just the inductance, so the energy is rather limited: here E = 0.5 I²*L = 19,2 mJ. So not really much. At 40 V, that is only some 0.5 mAs or 0.5 V rise in a 1000 µF capacitor. Due to losses the actual energy will be lower. So something like a 1000 µF capacitor and a supply / driver that can stand a 1 V voltage rise should be enough.The only exception would be, if the motor really has to work as a generator to slow down heavy parts. Than you might need a sink for the energy, e.g. a 2 quadrant supply or an extra circuit for over voltage limitation (e.g. a kind of power zener diode at 50 V).

author: Zero999
author_rank: Super Contributor
timestamp: September 16, 2016, 10:01:58 am
content: Quote from: Kleinstein on September 16, 2016, 09:49:10 amTL431 + some chunky power transistors.

author: nour
author_rank: Frequent Contributor
timestamp: September 16, 2016, 11:22:48 am
content: Thanks for the contributors.So basicly what I have understood if the output of a power supply have enough capacitance it would be ok, is that right !

author: Kleinstein
author_rank: Super Contributor
timestamp: September 16, 2016, 11:40:14 am
content: The capacitance is Ok to cope with the magnetic back EMF. So if the motor is not running very fast (e.g. less than 500 RPM, so it would normally not go up to the supply level) and does not need to break a heavy load fast, the capacitance is enough. But if the motor is really converting significant mechanical energy to electricity more (like the active sink / clamp circuit) might be needed. The limit somewhat depends on the driver and details on how fast it runs / stops.
Choose Siglent top 1000 or bottom 2000? - Page 1
Forum section: electronics / beginners

author: FriedMule
author_rank: Frequent Contributor
timestamp: December 27, 2018, 04:41:52 am
content: I am thinking of buying the Siglent SDS1204X-E 200MHz 4CH because it has 4 channels and 200MHz.The low end 4ch of the 2000 series costs a good bit more and do have better memory but is also way slower in MHzIs it possible to "upgrade" the 2000 series like you can do with Siglent's function generator so I can buy the low end and end up with the near top end?

author: jazper
author_rank: Regular Contributor
timestamp: December 27, 2018, 10:17:15 pm
content: Looking at the list here:https://www.siglenteu.com/digital-oscilloscopes/sds2000x/The SDS2104x has 100mhz bandwidth. This is the same as the 1104x-e in stock form, and is close to the low end of the 2xxx series. Do you really need 200mhz?

author: jazper
author_rank: Regular Contributor
timestamp: December 27, 2018, 10:29:14 pm
content: https://www.eevblog.com/forum/testgear/siglent-sds2000x-hack/A little searching turned this up, with some hardware mods it is possible...

author: tautech
author_rank: Super Contributor
timestamp: December 27, 2018, 11:43:47 pm
content: Quote from: FriedMule on December 27, 2018, 04:41:52 amYep links have been offered ....one more, look up the Siglent ads thread and have a read.However, look at this great summary of the differences between 1k and 2k models first;https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-vs-sds2204x/msg2070919/#msg2070919

author: FriedMule
author_rank: Frequent Contributor
timestamp: December 28, 2018, 01:51:50 am
content: No I may not need 200MHz right now, but nice to have:-) The decision is if the newer 1204 or the lowest end 2000 is the best choice.If the 2000 can be "upgraded" then I there is no question what is best on the other hand if I cant be upgraded, then the 2000 may not be worth it?Thanks for the link!!

author: jazper
author_rank: Regular Contributor
timestamp: December 28, 2018, 02:13:38 am
content: Respectfully, I disagree with you based on the post that tautech kindly posted.I think the 1000x series is a better buy based on what you have said. Especially considering you could get a 1104xe, do the software upgrade and get the logic analyser add-on in your price range
Choosing a diode for flyback SMPS. Average current or peak current? - Page 1
Forum section: electronics / beginners

author: debininja
author_rank: Contributor
timestamp: June 09, 2017, 03:58:41 pm
content: As you guys already know, well before I did, FBT secondary side peak currents are much higher than average output.For an example: an 1Amp average output current FBT might output around ~4.5Amps peak, which then slopes down to 0 (in 45% dtc. DCM).Question is: do I choose theaverage currentvalue as my limiting factor or theinstantaneous (peak)?Take for example, the SB240 (click here for datasheet). Also, would this diode be a good choice for a 5V 1A FBT SMPS?

author: fourtytwo42
author_rank: Super Contributor
timestamp: June 09, 2017, 04:16:15 pm
content: You need to consider both, if your peak current exceeds the diodes repetitive peak current rating it will fail. The average power involves the diodes dissipation and is usually quoted for a half sine, not very representative of an SMPS because the peak to average ratio is totally different but if possible calculate your average power and choose a diode capable of that. In all cases ensure your chosen diode is well able to handle the situation, not borderline or only just. Many converters have higher currents during startup charging output capacitors etc and this also needs to be taken into account.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 10, 2017, 12:48:12 am
content: If you use the basic Vf + Rs model, there is a linear power term (from Vf) and a quadratic term (from Rs). That is, power dissipated is: Vf * I + Rs * I^2.For a waveform, the power from Vf comes from average current, while that from Rs comes from RMS current.So it's definitely more than average, but not quite RMS, and certainly not peak.It gets more complicated if you include a more nuanced model of Vf (a power series, or the exponential proper), and temperature dependence. (Note that, as the diode is allowed to heat up, it becomes more efficient in the forward direction! And also less efficient in reverse -- watch out for that leakage at high temperatures.) You'd be better off SPICEing that, though.Why power? Until extremely high currents (above the surge rating), the limiting factor is heat. So the diode rating also depends on the heatsinking: a B340 with minimal pads is good for about as much as a (frame-lead) SOD-123F with a smaller die, but more heatsinking. (PMEGxxxx parts come to mind.)Small dies are also better for high frequency operation. This isn't a problem at your frequencies, though.Tim
Choosing a display for device - Page 1
Forum section: electronics / beginners

author: mmrvelj
author_rank: Newbie
timestamp: December 13, 2018, 04:40:07 pm
content: Hi allWe have subcontractors that design a device for us. Device is like appliance (1RU) that will be installed in 19" rack in server room.We are asked to define the display that will be put on front panel of the unit.The purpose of display will be to provide elementary status information, help with initial configuration, and in some case display some simplified graphical information (that might need updates up to 2 times per second).Some of the parameters:reliable operation 24/7 for 5 yearsable to display simple graphicsdoes not emit too much light (avoid distraction) - option where backlit (if there is one) can be turned on/off is acceptableheight not more then 38 mmcan be easily procurednumber of devices to be produced in one production batch: 10-20cost < ~50 $ per display (current idea might be increased if there is a good reason)I could really use a good advice/pointers on the type of display (technology, model) to choose. What should be taken into consideration when selecting the display?

author: james_s
author_rank: Super Contributor
timestamp: December 13, 2018, 04:53:41 pm
content: LCD would fit the bill. Since you want some graphics I'd go with a dot matrix type vs a character display. They are virtually immune to image burn and don't really degrade over time the way OLED does. You can easily adjust the brightness by controlling backlight current.
Choosing a good MCU and package PRO's/CON's? - Page 1
Forum section: electronics / beginners

author: DivineChaos
author_rank: Regular Contributor
timestamp: February 02, 2016, 02:08:54 am
content: Sup guys, me again with another "pick the guys brains" thread.I am at the point in my project where I need to pick an MCU to perform basic voltage detection and mode selection, along with keeping time.The MCU I am hoping to use will be in the same "package" as theTexas Instruments TPS60205which is SOIC .5mm pitch. Reason for that? well that's what it came in, and I'd like to keep the finished product uniform and that's also about the limit to my hand soldering skills as far as "that's really dang small" goes...I am hoping to remain in the 3.3v range and something that uses "AVR? programming"I don't really know if that's a thing. The coding that an Arduino uses.Any low power suggestions out there? I was looking at theAtmel ATtiny13Awhich appears to have 4 ADC pins, but maybe it requires too many external components? My goal is basically lowest power consumption in an SOIC package that requires few to no external components.Also, I have an FT232RL breakout that allows me to program an Arduino Pro Mini that I have been experimenting with.I just feel that maybe an MCU is overkill for a simple project like this:https://www.eevblog.com/forum/beginners/designing-a-super-complex-single-led-illuminator/Also, as the title suggests.. Is choosing a certain "package" like SOT or SOIC just a design choice or are there other benefits/drawbacks?

author: Pack34
author_rank: Frequent Contributor
timestamp: February 02, 2016, 07:45:31 pm
content: What platform are you most familiar with? If you just need a general purpose MCU with no real requirements, just stick with the brand that you're most familiar with. Then search for one that has enough I/O, the correct peripherals you need, and the package and price-point you're comfortable with.

author: DivineChaos
author_rank: Regular Contributor
timestamp: February 02, 2016, 09:22:06 pm
content: So package is basically just my choice? I kind of figured it may be, being that most chips come in several different packages.I guess Atmel won me over simply because of the Arduino.

author: Kilrah
author_rank: Unknown
timestamp: February 02, 2016, 09:40:42 pm
content: Yep, based on your manufacturing wishes/abilities. The exact same part is usually available in several different packages just for that reason of letting you pick the one you prefer for your particular application.

author: DivineChaos
author_rank: Regular Contributor
timestamp: February 02, 2016, 10:50:45 pm
content: Is it a bad design choice to have several different packages on one board or is that a typical thing to see?Do the people that do the pick and place really care basically? Cost benefits for a certain package?