hybridfree/eevblog-posts huggingface dataset:
Help Designing a 18650 charging circuit - MCP73831 - Page 1
Forum section: electronics / beginners

author: MabumisHuge
author_rank: Newbie
timestamp: March 15, 2024, 04:14:32 am
content: Hi there!I recently started designing some pcbs for a project I'm working on that contains a circuit to charge 2 18650 batteries in parallel. However when my assembled PCBs arrived, the MCP73831 started to smoke and died. I'm fairly sure I followed the example schematic pretty closely, besides some capacitors which i assumed were for noise.Below is a photo of the schematic as it was on the PCB, as well as the recommended layout from the datasheet. If someone can find a glaring cause for what I'm assuming was a short of the chip please let me know (or if the problem may be down stream).Cheers

author: ataradov
author_rank: Super Contributor
timestamp: March 15, 2024, 04:33:37 am
content: The datasheet has the whole section about capacitors and why they are necessary. Whether it would lead to smoking - hard to tell. It might go into some weird oscillation mode and die, for sure.

author: Peabody
author_rank: Super Contributor
timestamp: March 15, 2024, 04:42:50 am
content: Any chance you had the battery installed backwards?

author: MabumisHuge
author_rank: Newbie
timestamp: March 15, 2024, 04:49:21 am
content: Quote from: ataradov on March 15, 2024, 04:33:37 amYeah I defs missed that part when reading initially, complacency on my part from assuming they were only for filtering. Upon reading datasheet does say MAY be necessary, however I would be quite surprised if this was the sole cause.Quote from: Peabody on March 15, 2024, 04:42:50 amBattery is installed correctly, further down in the circuit the battery voltage is converted to 3.3V to power an esp32, which I was able to flash.

author: ataradov
author_rank: Super Contributor
timestamp: March 15, 2024, 04:55:03 am
content: Quote from: MabumisHuge on March 15, 2024, 04:49:21 amWell, LM1117 is infamous for its instability with incorrect capacitors, which leads to overheating. I don't think it overheats enough to smoke, but still.It is hard to predict how this device may behave. Your best test is to try it in isolation without a battery or any other circuits attached.

author: MabumisHuge
author_rank: Newbie
timestamp: March 15, 2024, 05:18:39 am
content: Quote from: ataradov on March 15, 2024, 04:55:03 amHmm maybe the capacitor is the cause then, downstream in the circuit i had a 22nf instead of the intended 4.7uf.Being a factor of over 200 off on the value might have had an effect if they are temperamental 😅Thanks for the advice, ill update the circuit and see how it goes
Current Shunt Measurement with 20kHz Sampling and 1mA Resolution - Page 1
Forum section: electronics / beginners

author: jonwilhelmjr
author_rank: Regular Contributor
timestamp: November 18, 2024, 02:06:39 am
content: I'm working on a project to design a current shunt measurement and need help with both the circuit design and code implementation. As a newbie, I'm specifically interested in understanding how to implement an ADC in this setup. I want to measure the current of a motor that will use less than 3 Amps.Specifications:Maximum current: 3ADesired resolution: 0.001A (1mA)Sampling rate: 20kHzPrecision and accuracy are very important.What I Need:1. Complete Circuit Solution:Shunt resistor: What value and type would you recommend for this current range and resolution?Amplification: Should I use an instrumentation amplifier like INA240? Any suggestions for noise filtering or gain settings?ADC: I’m considering a 16-bit ADC like ADS1115 or ADS1262 to meet my resolution and sampling requirements. Are there better options I should explore?2. Microcontroller and Code Design:Which microcontroller would work well for interfacing with the ADC and processing data at this sampling rate?Any examples of implementing an ADC (code, library recommendations, etc.) would be greatly appreciated.3. Learning Resources:As I’m new to ADCs and precision measurements, are there any guides, tutorials, or reference designs you’d recommend to help me understand this better?I’m excited to learn and dive into this project, so any advice or suggestions from the community would be highly valued. Thank you in advance for your time and expertise!

author: Doctorandus_P
author_rank: Super Contributor
timestamp: November 20, 2024, 12:48:58 am
content: I dare say that the experience you gain by building circuits is more important then just getting this thing "up to specs". People here can give advise here, but it's unlikely they will take on your whole project and present it to you on a plate. Build a few circuits, do some measurements, and then come back to ask more specific questions.
Help designing common emitter amplifier for RF - Page 1
Forum section: electronics / beginners

author: antenna
author_rank: Frequent Contributor
timestamp: November 11, 2021, 10:19:33 pm
content: If I follow the method shown in the ARRL handbook, I choose my quiescent current, my supply voltage and my gain. If I follow along with W2AEW's video on CE amplifiers, I start with my desired output impedance and a small degeneration voltage shooting for max gain.There is an article by VA3IUL titled "Very low phase noise vackar VFO" that mentions general rules regarding good oscillator designs (such as choosing devices where fT ≤ 2xFreq and choosing devices with a higher max Ic than intended in the circuit) and I am wondering if such rules apply to amplifiers or if there are similar but different rules for amplifiers.Thanks!
Help determining replacenemt capacitor value - Page 1
Forum section: electronics / beginners

author: Dalek84
author_rank: Newbie
timestamp: July 08, 2013, 05:30:21 pm
content: Hi,I have a control panel (Photos attached) that has a bad capacitor, unfortunately the cover is gone, so I have no Idea what the value of the capacitor is.I am sure there is a way to determine the value, but I am an amateur and have not come across this particular problem yet.Any help would be greatly appreciated

author: Simon
author_rank: Unknown
timestamp: July 08, 2013, 05:33:13 pm
content: If you are talking about "the thing" with wire around it and a part shell that is an inductor. sure it is broken ?

author: Lightages
author_rank: Unknown
timestamp: July 08, 2013, 05:37:12 pm
content: Yes, that must be an inductor, and the capacitor beside it appears bad too from the bulge. I would try replacing the capacitor first. It is clearly marked. The inductor can be made if you need to.

author: Paul Price
author_rank: Super Contributor
timestamp: July 08, 2013, 05:59:43 pm
content: The tall capacitor looks fine to me, from your photo, the inductor(with the copper wire showing on the side) looks severely distressed. The trouble might be a shorted transistor or MOSFET the inductor connects or a diode the inductor connects to, but the large 330uF capacitor looks perfectly fine.Some circuit short circuit has overloaded the current through the inductor and caused it to overheat and expose the wire winding. The inductor may need to be replaced if you can or tell with your ohm-meter that the wire exposed has heated to a point to burn off the enamel insulating coating, but first you must try to find what is short circuited to cause it to overheat.It is not the large capacitor, in my guesstimation.
Help diode identification, schematic - Page 1
Forum section: electronics / beginners

author: exico91
author_rank: Newbie
timestamp: April 26, 2023, 02:43:49 pm
content: Hello,I'm trying to build a esphome-based hw integration for a automatic garage door. The manufacturer has two components that you can buy to integrate the controller with other systems but I'd like something more "stealth".Anyway, this mini-board has a diode on it and my knowledge of eletronics is lacking, I've been making some boards by copying and adapting designs that already exists and with some trial and error.I attached a couple photos and the schematic of the board, it would be nice to find a replacement for the aftermentioned diode, better if a smd version.I do not know what SommerSIG contains, my guess is a PWM signal but AnalogSIG is actually read by a ESP8266 adc pin device and output a 0,05v signal if closed and a 0,005v signal if open

author: DavidAlfa
author_rank: Super Contributor
timestamp: April 26, 2023, 03:37:24 pm
content: It's for driving inductive loads, like relays, protecting the transistor against voltage spikes.

author: exico91
author_rank: Newbie
timestamp: April 26, 2023, 04:44:54 pm
content: Thank you for your answer but pardon my ignorance.So a 1N4001 generic diode would do the job?

author: wasedadoc
author_rank: Super Contributor
timestamp: April 26, 2023, 04:55:43 pm
content: It is unusual for the collector of a NPN transistor to be connected to ground. Are you sure your schematic is correct? In the photo it looks like the tab (which is usually collector) is connected to the diode whereas your schematic has the emitter connected to the diode.

author: exico91
author_rank: Newbie
timestamp: April 26, 2023, 05:37:31 pm
content: the correct symbol is different, I choose the worng symbol in the schematic. The STN3NF06 is a mosfet ->https://www.mouser.it/datasheet/2/389/stn3nf06-1851441.pdfPIN 1 is GatePIN 2 is Drain (and also 4, the TAB)PIN 3 is SourceI can confirm that pin 3 is connected to groundI added a schematic with the correct symbol

author: exico91
author_rank: Newbie
timestamp: May 04, 2023, 04:29:46 pm
content: Can i have a confirmation for the diode? I do not want anything to explode

author: gamalot
author_rank: Super Contributor
timestamp: May 04, 2023, 04:39:04 pm
content: Quote from: exico91 on May 04, 2023, 04:29:46 pmIt looks like a 1N4148.
Help figuring out stepper motor - Page 1
Forum section: electronics / beginners

author: Silenus
author_rank: Contributor
timestamp: January 26, 2015, 02:17:07 am
content: I have astepper motorI scrapped from a printer and I am trying to figure out how to run it. It has 5 wires so my first guess is that it is unipolar with a common tap on both coils, this is confirmed from resistivity tests. Now in the datasheet it says to drive it 2-2 phase excitation (bipolar driving). Does that mean I can't drive it as a unipolar system with the centre tap connected to Vcc and the 4 coils going through a BJT to ground? I've hooked it up as a unipolar system with 1-1 phase excitation but the motor just makes jittering noises with no visible movement no matter which combination I have the wires in. Any advice?

author: Rerouter
author_rank: Super Contributor
timestamp: January 26, 2015, 02:24:03 am
content: from the center wire, all 4 others should measure the same resistance, or very close to, he will be connected to supply, the other 4 will be switched low in sequence, should be the same as a 6 wire unipolar,it is likely that it requires overlapping steps rather than just 1 on at a time, e.g. A, AB, B, BC, C, CD, D, DA.

author: Andy Watson
author_rank: Super Contributor
timestamp: January 26, 2015, 02:35:59 am
content: With four wires and a common you can usually choose either unipolar or bipolar drive.Down at the bottom of this page is a link to a pdf of "Product Information", it gives the wiring diagram and shows both unipolar and bipolar configurations.http://www.mitsumi.co.jp/latest/Catalog/compo/motor/index_e.htmlWhat voltage are you using? The data sheet specifies 21 to 26V. Your description suggests that there might not be enough drive.

author: Silenus
author_rank: Contributor
timestamp: January 26, 2015, 02:42:25 am
content: I'm giving it 24 V and I just programmed in a 2-2 phase excitation, now the motor is turning in time with the pulses but it was drawing an amp and started getting warm so I shut it off. Is that sort of current and temperature normal?
Help figuring out which plug do I need for this? - Page 1
Forum section: electronics / beginners

author: R-M-I
author_rank: Contributor
timestamp: June 09, 2012, 07:10:27 am
content: I need to buy some 5-pin JST plugs with wires crimped onto it..The problem is, there are heaps of different 5pin connectors around and there are no markings on the connector itself(that I can see)..This is the connector I'm talking about:It's about 9mm long, 5mm tall..I'd LOVE it if anyone could link me to a eBay-item or shop that I can buy it from..

author: ikrel
author_rank: Contributor
timestamp: June 09, 2012, 07:21:30 am
content: Sparkfun might have what you're looking for:http://www.sparkfun.com/products/10360

author: R-M-I
author_rank: Contributor
timestamp: June 09, 2012, 07:30:16 am
content: I have that exact plug/connector.. And unfortunately it does not fit at all..

author: ikrel
author_rank: Contributor
timestamp: June 09, 2012, 07:39:48 am
content: they sell the whole package you could replace the connector on the board?

author: R-M-I
author_rank: Contributor
timestamp: June 09, 2012, 07:49:06 am
content: I see that.. But I figure it would be a advantage if the connector-pins would actually fit into the board-holes if I were to solder in a new connector.. I don't want to replace the connector on the board... I simply want the plug that fits into the connector on the boards I already have.. I've contacted JST in the US and UK.. Hoping they will be able to help me out..

author: Short Circuit
author_rank: Frequent Contributor
timestamp: June 09, 2012, 11:02:42 am
content: JST ZH perhaps? 1.5mm pitch 5-way is 9mm widehttp://www.jst-mfg.com/product/detail_e.php?series=287

author: R-M-I
author_rank: Contributor
timestamp: June 09, 2012, 11:38:15 am
content: Hmm.. That LOOKS about rightI'll give it a trythank you!See the pitch is 1.5mm, so I guess it's the right connectorEDIT:Just bought 10 of them on eBay.. I'm sure I can use it for something if it can't be used for the boards I have
help find in digikey / mouser - Page 1
Forum section: electronics / beginners

author: djacobow
author_rank: Super Contributor
timestamp: June 17, 2017, 10:14:28 pm
content: I'm working on a board that will plug directly into a Raspberry Pi's GPIO pins without an intervening IDC cable. In order for the board to clear the Ethernet and USB connectors, the header socket needs to be unusually tall.Adafruit has a part like this for the job:https://www.adafruit.com/product/1658OK, but not for $2. I just cannot figure out what the magic keyword is to find these guys from the more bulk-friendly suppliers. I just find regular height 0.1 types.I also only need to connect to the first few positions of the RPi header, so I'd ideally prefer 2x5 rather than 2x20.

author: djacobow
author_rank: Super Contributor
timestamp: June 17, 2017, 11:01:05 pm
content: Thanks, blueskull. That's a bummer, but at least I know it wasn't a problem with my digikey and mouser search-fu.

author: Monkeh
author_rank: Super Contributor
timestamp: June 18, 2017, 01:45:18 am
content: Samtec ESW series:https://www.samtec.com/products/eswQuickly ran through their ordering system and got quoted $0.88/ea for 100 units of 2x5, tin plate, 4.8mm tail and 13.6mm box.

author: djacobow
author_rank: Super Contributor
timestamp: June 18, 2017, 07:16:19 pm
content: This is great, thanks monkeh!
Help finding a connector(wire to board, 2.54mm) - Page 1
Forum section: electronics / beginners

author: senso
author_rank: Frequent Contributor
timestamp: July 26, 2017, 11:46:22 am
content: Good morning, I have been searching for this thing for hours both on Mouser and Digikey.Its a fairly basic 3 positions, female, 2.54mm pitch, but the locking mechanism is a bit different, others will fit, but I would love to find an equal connector, its for a small adapter box to change connectors in a POS, if anyone wants to know what is the use case.I have a couple photos of the original connector, but they are not the best, sorry.The most similar ones seem to be:SWH25B-NULC-S03-UU-BRThe IPM1-XX-X-XX series from SamtecMTA 100 series from TENone as both the middle pin and the bumps that lock the connector in place, but for what its worth, the wiring that gets out of said connector can be plugged either way, so even 100mil pin headers fit, just not very professional.Any ideas?For reference the DC-IN is a CUA part and took me a couple days to discover it.
help finding a digital encoder for fisher and paykel wall oven OB30SDEPX3N - Page 1
Forum section: electronics / beginners

author: dmbe11
author_rank: Newbie
timestamp: December 12, 2024, 05:04:43 am
content: encoder.pdf(3557.59 kB - downloaded 36 times.)I have a wall oven that the digital encoder shaft broke, making it unusable. I have tried to find the part for several days with no luck.encoder.pdf

author: Poroit
author_rank: Frequent Contributor
timestamp: December 12, 2024, 06:09:38 am
content: G'day dmbe11,Is this the part you need?https://www.statewideapp.com.au/fisher-paykel-oven-function-encoder-module-or90sci4w1-578058

author: dmbe11
author_rank: Newbie
timestamp: December 12, 2024, 07:42:22 pm
content: Thank you, but I dont think so. While my oven is newly purchased, it is an older series. The new series uses a small PCB and mine just has the encoder. That is why wondered if an alternate encoder with the appropriate number of detents.
Help finding a jellybean optocoupler for PWM - Page 1
Forum section: electronics / beginners

author: rubemjrx
author_rank: Newbie
timestamp: January 20, 2022, 11:38:02 am
content: Hello, I need a relatively low cost and easily available optocoupler for controlling a half bridge driver (IR2104) with PWM. This is for driving a DC motor, so I need it to be able to switch at least 5kHz with reasonable precision (10 bits maybe?), ideally a higher frequency but not really so much (using IGBTs).I have tried looking at what local electronic stores have in stock, but haven't found anything enlightening.Thanks!

author: Zero999
author_rank: Super Contributor
timestamp: January 20, 2022, 02:31:32 pm
content: The IR2104 is obsolete.I recommend an isolated gate driver. The ADuM5230 is nice. A contractor designed a solenoid driver using it. A big advantage is it contains a built-in isolated power supply. A complimentary pair of emitter followers can be added to the outputs to give a higher peak output current.https://www.analog.com/media/en/technical-documentation/data-sheets/ADuM5230.pdf
Help finding a Vectorviz WP-30 Isolation Transformer Owners Manual & Schematic!! - Page 1
Forum section: electronics / beginners

author: finom1
author_rank: Regular Contributor
timestamp: July 17, 2017, 03:02:55 pm
content: Hello,Does anyone have a Owners Manual & Schematic for a VectorViz model WP-30 Isolation Transformer?It has been over a year and I have not found a Owners Manual & Schematic. If someone could help me maybe I can help you with the schematics I have in file cabinets I purchased.Thank you!

author: finom1
author_rank: Regular Contributor
timestamp: July 17, 2017, 10:12:13 pm
content: It looks just like this one:Thank you.
help finding coloured wire - Page 1
Forum section: electronics / beginners

author: tehtehteh
author_rank: Regular Contributor
timestamp: February 04, 2017, 05:16:35 pm
content: I'm looking for a pretty standard multi-strand flexible cable, outer diameter less than 1mm, at least 2 amps of current............but I need it in a dark green colour and I can't find it anywhere, all the greens I can find are too bright, I know they're out there somewhere because I've seen christmas lights with wires this colourdoes anybody know a place that sells lots of colours of wire? can anyone help me?

author: KMoffett
author_rank: Regular Contributor
timestamp: February 04, 2017, 05:27:31 pm
content: Googled: dark forest green hookup lead wireMaybe this:https://www.google.com/search?q=forest+green+hookup+wire&tbm=isch&imgil=EIPiV1FYYmfA6M%253A%253BFpdmJRAhpKfFNM%253Bhttp%25253A%25252F%25252Fwww.jameco.com%25252Fz%25252F815-5-26-AWG-Green-Stranded-Tinned-Copper-Hook-Up-Wire-100-Feet_734506.html&source=iu&pf=m&fir=EIPiV1FYYmfA6M%253A%252CFpdmJRAhpKfFNM%252C_&usg=__8LVRJjUquHRWq5KJuksz5Wf4yUE%3D&biw=1600&bih=740&ved=0ahUKEwiz5rrc-fbRAhUD6YMKHQmtAhkQyjcIKQ&ei=PQ2WWPPTOoPSjwSJ2orIAQ#imgrc=EIPiV1FYYmfA6M:or this:http://www.mouser.com/Wire-Cable/Hook-up-Wire/_/N-5ggs?P=1z0xf2e&pop=1amivBut you can't always trust photo colors. More vendorsKen

author: tehtehteh
author_rank: Regular Contributor
timestamp: February 04, 2017, 07:39:03 pm
content: second one.... 400 euros?!?!I thought it would be easier to find than this, it's only dark greenthe way I can describe the colour is it's meant to blend with a christmas tree

author: KMoffett
author_rank: Regular Contributor
timestamp: February 05, 2017, 01:35:14 pm
content: http://www.remingtonindustries.com/hook-up-wire/hook-up-wire-26-awg-stranded-green-25-length/Their green looks dark.Ken

author: Yansi
author_rank: Super Contributor
timestamp: February 05, 2017, 01:39:35 pm
content: Quote from: tehtehteh on February 04, 2017, 07:39:03 pmThats a teflon wire. Hence the price.
Help finding component? - Page 1
Forum section: electronics / beginners

author: wadmancpu
author_rank: Contributor
timestamp: June 30, 2022, 03:06:54 pm
content: Can someone help me find this power supply relay? Thanks in advance.

author: Zero999
author_rank: Super Contributor
timestamp: June 30, 2022, 06:10:57 pm
content: It doesn't look like a relay. My guess is it's an NTC resistor, a type of inrush current limiting device.https://circuitcellar.com/research-design-hub/inrush-current-limiters-in-action/

author: Doctorandus_P
author_rank: Super Contributor
timestamp: July 02, 2022, 07:30:53 am
content: Where does it come from? How was it used in a circuit? how were the wires connected?Refrigerator motors tend to have some form of PTC. When it's cold there is some significant current through a starting winding, and when it heats up this current gets reduced a lot.
Help finding datasheet MM056 9B08 - Page 1
Forum section: electronics / beginners

author: ICTravis
author_rank: Newbie
timestamp: November 22, 2014, 01:01:35 am
content: I have Google-ed quite a bit and tried the datasheet look up sites in the sticky above. Called a few electronic engineers I know... Nothing. Just want to know what functions this performs for now. Thank you!

author: miguelvp
author_rank: Super Contributor
timestamp: November 22, 2014, 02:24:51 am
content: Maybe adding where the board belongs to might help.Could be a custom chip or just a custom label for some common IC

author: ICTravis
author_rank: Newbie
timestamp: November 22, 2014, 02:46:46 am
content: Sure. It is a component in the digital speedometer in an early eightys Mitsubishi automobile. This chip resides underneath a futuba 3 digit display part number: 4-GT-50Z or 457175-0050. I believe the chip contains the logic for lighting up the display. Currently the display stops reading above 136kmh. Wanting to reverse engineer the circuit in order to attempt to figure out how to modify it to continue displaying at faster speeds. In another domestic market a nearly identical speedo is reported to display up to 180+ and there are digits to go to 299. Unfortunately no information is available as far as schematics or otherwise for either my speedo or the 180+ speedo and I do not have a 180+ speedo at my disposal. I have already verified that the pickup that converts the speedo cable rotation into an square wave signal for the speedo continues its modulation well past the displays limit. Something else worth mentioning is that around this IC are pads and printing indicating additional circuitry not present on this board so I am hoping this suggests that maybe some part of it is for increasing the display limit.And back to my initial request. If anyone is able to find anything about this chip I would love to know specifically the steps you took to find the information so that next time hopefully I can do this on my own. Frustrating having dug this far into it and not knowing what to do next...Edit: One last thing is that there are 42 pins on the chip if that is of use at allThank you,ICTravis

author: ICTravis
author_rank: Newbie
timestamp: November 22, 2014, 02:53:26 am
content: Same number of pins similar part number prefix similar function. Am I getting close?http://www.micrel.com/_PDF/mm5450.pdf

author: amyk
author_rank: Super Contributor
timestamp: November 22, 2014, 03:54:19 am
content: The logo is that ofNippon Denso, and both from that and its age, you are basically not going to be able to findanydatasheet for it, much less one in English and not Japanese; my guess is that it's a mask-ROM MCU programmed as a frequency counter and calibrated to display speed. If you trace the schematic and figure out how the display is driven and where the input signal comes from, it shouldn't be too hard to replace it with an MCU of your own choosing (e.g. PIC, AVR, 8051, etc.)
Help finding examples of STM32 USB Host HW designs - Page 1
Forum section: electronics / beginners

author: agehall
author_rank: Frequent Contributor
timestamp: May 03, 2021, 08:22:42 am
content: I would like to play a bit with STM32 as an USB host (for HID devices) and I would eventually like to roll my own board for this. Does anyone know of any good sample projects (especially HW designs) that I can look at to get some ideas of what is right/wrong here? The exact MCU doesn't matter - nothing has been decided for my project yet, so I'm more interested in how to deal with things like providing bus power in a 3.3V system.Googling for this gives me a bunch of USB DEVICE projects but when it comes to the host side, I just can't seem to find anything. Maybe I'm just overcomplicating this in my mind and that is why I can't find anything...

author: harerod
author_rank: Frequent Contributor
timestamp: May 03, 2021, 07:16:34 pm
content: Have tried looking at OTG designs?
Help finding info on Exar XR ICs? - Page 1
Forum section: electronics / beginners

author: dentaku
author_rank: Frequent Contributor
timestamp: January 22, 2015, 03:05:29 pm
content: I have an old APC UPS with ICs with dates from around 1997. I'm not trying to fix it, just looking at the different parts inside it.It's got 3 that are interesting but I can't find anything about them.One is actually labeled with the official XR logo (I know that's EXAR). It's an XR 3602010. The other two don't have the Exar logo but are 3602020 XD and 360-2002B which is directly connected to the pins of the serial port).I find Exar parts interesting but I haven't been able to find any datasheets for these parts.I've searched their site but that doesn't help.All I ever get is obscure Chinese chip seller sites.http://www.aliexpress.com/item-img/10PCS-XR3602010-3602010-DIP/2040490616.htmlIs this kind of stuff just impossible to track down datasheets for?

author: katzohki
author_rank: Frequent Contributor
timestamp: January 22, 2015, 03:31:15 pm
content: Standard sources:datasheetcatalog.comalldatasheet.comdatasheets.comfindchips.comIf the standard sources don't turn up anything then email or call Exar. I'm sure they will be able to identify the chips and provide datasheets. I didn't find anything easily in 2-3 minutes so that's probably what you'll have to do.

author: wraper
author_rank: Unknown
timestamp: January 22, 2015, 03:49:04 pm
content: Quote from: katzohki on January 22, 2015, 03:31:15 pmThey won't provide anything as those are custom or rebadged parts with APC part numbers.

author: dentaku
author_rank: Frequent Contributor
timestamp: January 22, 2015, 04:00:15 pm
content: Quote from: wraper on January 22, 2015, 03:49:04 pmI was wondering about that.As a fan of DIY synthesizer stuff I like finding XR chips but it's annoying when the real part numbers are removed. The other two without the XR logo are probably nothing interesting anyway.

author: bktemp
author_rank: Super Contributor
timestamp: January 22, 2015, 04:25:44 pm
content: APC widely used their own part numbers. Try to find a schematic for that or a similiar UPS (most of them have only little differences like number of mosfets used for different output power versions).If it is next to the serial port it is probably something simple as a RS232 level converter.
Help finding info on that Philips IC (QQ1RWU-02) - Page 1
Forum section: electronics / beginners

author: samueltc
author_rank: Newbie
timestamp: January 22, 2015, 10:23:33 pm
content: Hi,I'm trying to get more info on that IC. I've tried google + the sites on the "Datasheet Database" thread w/o success. It's a Philips QQ1RWU-02 3349A 419KC kSM94232 (see attached image).Any idea?Thanks!Sam

author: bugs
author_rank: Contributor
timestamp: January 23, 2015, 04:15:37 pm
content: Probably a Philips/NXP PCD3349Ahttp://www.digchip.com/datasheets/parts/datasheet/364/PCD3349A-pdf.php

author: samueltc
author_rank: Newbie
timestamp: January 25, 2015, 07:27:55 pm
content: Cool! That make sense: that's inside a payphone (see attachments)!Thanks,Sam
Help finding out reason for electrical phenomenon (FM radio from nowhere!) - Page 1
Forum section: electronics / beginners

author: Syllith
author_rank: Regular Contributor
timestamp: March 02, 2017, 06:20:48 am
content: I'm an experienced electrician working at a car audio installation shop and today my salesman brought something quite interesting to my attention. We have a demo wall with many speakers, subs, amps and radios. Everything is connected via a matrix switch. There are separate switches for the radios, speakers, amps, etc. When, and only when, you have either a sub amp or a 4 channel amp selected, as well as a speaker of course, you can hear FM radio playing quietly (but not that quietly) out the speakers (mostly the rears), even when the selected radio is muted and not on the FM source. So I think the answer is obvious and one of the other radios is playing FM and it's somehow just bleeding into the audio lines. So out of curiosity I turned off every single radio and low and behold, still FM playing through. Now, I'm thoroughly confused. How is it possible that without something to cancel out the carrier wave can actual radio be playing through a speaker? Seems crazy, right? I'm sure I turned every radio off. None of them have antennas plugged in. When I turned off one of the 2 amp channels, it went away a little. Only when I turned them both off did it completely go away. If you turn the volume up on the selected radio it overpowers the FM quickly so it isn't a problem to demo.What's going on here? I'm beyond clueless.

author: helius
author_rank: Super Contributor
timestamp: March 02, 2017, 06:26:55 am
content: It's more common to see this type of interference from AM radio, as it can be received by all manner of wires and demodulated by just a diode. If it really is FM that is more surprising, but all it really requires is a circuit that reacts with variable gain (or attenuation) dependent on frequency. The crossovers in a speaker or subwoofer are a candidate for such a circuit; although they are designed to work at audio frequencies, it's possible they have a harmonic response at RF frequencies as well. There could also be some component with a parasitic oscillation close to the FM carrier frequency, creating an unintentional downconverter.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 02, 2017, 01:25:00 pm
content: Newsflash: your radios are badly designed, and fail electromagnetic susceptibility -- somewhere in the signal path. Complain to the manufacturer, or buy brands that don't suck.In the mean time, ferrite beads on the various cables might help, but you can usually only get a slight reduction in interference that way.Tim
Help finding out what a component is. - Page 1
Forum section: electronics / beginners

author: eirikrrrr
author_rank: Newbie
timestamp: November 07, 2024, 07:50:51 pm
content: Hello, newbie hereI recently got an old sewing machine called Norsy Type 4 (which i think is just a rebranding of an Anker Phoenix Gloria Automatic).And it runs! which is great!, but when i opened it up to clean it, i saw that the first component the power goes in to, looked broken.Might not be anything dangerous, but i don't feel super safe having 240 volts enter a thing like that.I have added pictures of the broken par and a text of what i think it says on it.I have as well added a picture of the engine.To me it looks like the broken part might be multiple parts? as the first line is a capasitor, and the second line is a fuse, but thats just guesswork through googling. any ideas of what it might be and how i could go about replacing it?PS: i dont mind soldering as long as i know what goes where.Thanks a bunch in advance

author: NE666
author_rank: Frequent Contributor
timestamp: November 07, 2024, 08:38:12 pm
content: That's a mains EMI (interference) filter and specifically, one of its capacitors has 'let go'.Since the metalised film of the capacitor is now exposed, and maybe at mains potential, I'd be inclined to either remove it completely (using a suitable mains cable joiner to join either the mains input to the power switch, or the motor to the power switch directly, depending on where in that chain the filter already is), or replace it with a suitably rated new unit.

author: Kim Christensen
author_rank: Super Contributor
timestamp: November 07, 2024, 08:38:57 pm
content: It's probably just a line filter to prevent EMI from the motor from interfering with the radio/TV.Modern versions come in various forms:

author: Doctorandus_P
author_rank: Super Contributor
timestamp: November 07, 2024, 09:21:12 pm
content: Yes, it's a filter.The second line is not for a fuse, but it's the nominal max current rating for the filter.But I am a bit surprised I don't see any inductors in there.

author: eirikrrrr
author_rank: Newbie
timestamp: November 10, 2024, 02:26:55 pm
content: Thank you all so much for the repliesvery greatful!!Would anyone maybe know of a filter that would be suitable for this machine?
Help finding sensor identification (A3030) - Page 1
Forum section: electronics / beginners

author: Andy-In_over_my_head
author_rank: Regular Contributor
timestamp: December 25, 2016, 04:05:35 am
content: Could someone please help me find the datasheet on this? (photo attached)A3030B0542FI'm pretty sure it's a photohelic micorchip sensor... it looks fun...Why is it that some products are just so damn hard to find data on?I understand I'm new to all of this, but most of the time, I can search for 30 minutes longer and find something...But other times, I get this issue..

author: chicken
author_rank: Frequent Contributor
timestamp: December 25, 2016, 05:15:55 am
content: Looks like an optical mouse sensor, Avago ADNS-3030.Unfortunately, the datasheets for the more modern ones are no longer easily available, but here's a reference design by Atmel that uses this sensor:http://www.datasheetarchive.com/dl/225078a66cc267b881da33780f313af7782c02/P/adns-3030Edit: There are datasheets for several ADNS-30x0 available, maybe one is close enough to the 3030.http://www.alldatasheet.com/view.jsp?Searchword=ADNS-3030
Help: FLICKERING LCD screen minicomponent - Page 1
Forum section: electronics / beginners

author: ALP2022
author_rank: Newbie
timestamp: January 11, 2022, 04:29:13 pm
content: Hi! The LCD screen of my minicomponent started flickering months ago but now is definitely more noticeable and I'm afraid it will be a problem in the future. The player itself works well, no problems with sound of anything though.At first I thought it was a electricity problem (I'm really new here) but no.I have tried:-cleaning it-checking cables (they may be loose but not so much, see picture). If thats the case I don't know if I can just replace them or contact a professional.Would you help me, please?
help fluorescent tube with dimmer - Page 1
Forum section: electronics / beginners

author: g-lock_dk
author_rank: Contributor
timestamp: August 02, 2024, 10:17:52 am
content: Hello everyone,I have a fagerhult loop light fixture that is supposed to allow dimming of the light by applying 1-10V to two terminals. Unfortunately, the datasheet that came with it has been thrown away, so I'm looking for some help to get it working.Inside the fixture, there are two Philips HF Regulator II units. I have attached pictures of the nameplate, connector, and HF Regulator II units for more context.I am using 230V mains.Can anyone guide me in the right direction regarding the connection and dimming of the lights?Thank you in advance for your help!

author: squadchannel
author_rank: Frequent Contributor
timestamp: August 02, 2024, 10:50:16 am
content: checking continuity between the terminal marked with a red pen and ballast #14 and #15.I couldn't find any information, but I did see a website that mentioned some sort of external dimming controller.

author: perieanuo
author_rank: Frequent Contributor
timestamp: August 02, 2024, 12:20:50 pm
content: my bet if you apply something between 0-10V on [DC= DC-] inputs you will get your dimmer function.in fact philips says exactly this herehttps://www.lighting.philips.com/prof/lighting-electronics/fluorescent/fluorescent-dimming-gear/hf-regulator-ii-for-tl5-lamps/LP_CF_HFR2ANT5_EU/familyin the leaflet:Benefits• The lamp power can be dimmed from 1 to 100% via the Analog control input (inaccordance with the 1-10 V industry standard)br
Help for a question - Page 1
Forum section: electronics / beginners

author: Cujo
author_rank: Regular Contributor
timestamp: February 27, 2020, 07:38:28 am
content: I'm having trouble to answer all the questions. So I would love some worked help thanks

author: Nusa
author_rank: Super Contributor
timestamp: February 27, 2020, 10:00:52 am
content: You need to know the rules you are being tested on to know the answers, but don't forget the "graphically show" part of the question.

author: rstofer
author_rank: Super Contributor
timestamp: February 27, 2020, 03:59:08 pm
content: What you need to do is use a fine tip pencil to draw vertical 'cursors' at the 4 points where the waveform crosses 1V (10%) and 9V (90%). Take the left two cursors (10 and 90%) and measure the time between them. This is 'rise time'. Take the right two cursors and measure the time between them. This is the fall time.The definition of 'pulse width' varies, read your book. One definition would be to take the time between two cursors at Vcc/2 or 5V. So, draw two more cursors and measure the time between them.Page 8 here:https://www.ti.com/lit/ds/symlink/sn74ls04.pdfThere are a lot of examples that are working on Vcc = 3V.
Help for BMS design  - Page 1
Forum section: electronics / beginners

author: sjd.aliyan
author_rank: Contributor
timestamp: June 12, 2016, 04:01:31 pm
content: Hi all.I want to use li-ion battery pack for couple of my projects.They are all kind of voltages and cells,from 12 to 50v.I want to design a BMS without limitation in number of cells or at least with minimal change.so i dont like to use bms ic's.I think it would be possible with a MCU +precise ADC and a couple of mosfets and some other stuff.Can anyone help me?
Help for choosing power supply for steppers and Peltier coolers - Page 1
Forum section: electronics / beginners

author: larsdenmark
author_rank: Regular Contributor
timestamp: May 19, 2014, 02:51:38 pm
content: HiI have started to work a little bit with an Arduino going through the first examples of blinking an LED and playing with a servo motor. Everything works fine so far. I have a small bench power supply to power the servos, but it is not powerful enough to power my 12V stepper motor (for which I have a shield).Should I buy a larger bench power supply that can deliver the power I need or am I better off choosing a fixed current power supply often seen used for CNC machines? My next experiments will involve a few stepper motors and some small 12V Peltier elements so I could easily be using 80-100W.I live in Europe if that matters.

author: Paul Price
author_rank: Super Contributor
timestamp: May 19, 2014, 07:04:00 pm
content: For the price of free, you can find discarded common wallwart power supplies or laptop power supplies, Many wallwarts are 12V at rated load(.8 to 2Amp), either can be fixed to 12V by a few 7812 regulator chips on a heatsink. These will do fine for <4amp steppers and many are discarded and the cost is free. A discarded PC power supply can deliver 12V at 8-amps and can be found in any discarded desktop PC.If you have money to burn to keep your Peltiers cool, and if you need about 100W, look and you will find for cheap on ebay. Search for switching power supplies/battery chargers.If you need large heatsinks, you will find them in any PC power supply.

author: larsdenmark
author_rank: Regular Contributor
timestamp: May 20, 2014, 09:15:38 am
content: Thanks PaulI think I'll go for the free (or almost free) options now. Ebay seems like a nice place to look.Lars
Help for connecting minibutton - Page 1
Forum section: electronics / beginners

author: CellMarc
author_rank: Newbie
timestamp: October 01, 2024, 01:22:39 pm
content: Hi. I premise that I'm a complete newbie in electonics (I only know how to solder somewhat), so eventually sorry for this question may look banal to experienced users.I have a 3d printer whose second fan (generally the one for cooling the abs) I don't use, thus I would like to take its 2 wires and connect 'em (either soldered or with pins/minijack) to this mini button in order to fire up a led strip which is placed on the feet of the printing cartridge.How to?
Help for convert 12v 3A DC to 5v 3A DC! - Page 1
Forum section: electronics / beginners

author: rozeh
author_rank: Regular Contributor
timestamp: February 13, 2014, 04:47:56 pm
content: Hi everybodyI have a charger that it give me 12v 3A DC output. now I want to change it untill give me 5v 3A DC but when see to it, it mix up me. look at it:in below picture, you can see to IC that I determinated by number 1 and 2.the number 1 IC is smk0760and the number 2 is mbrf20100ctin your opinion, How can I do it?

author: mariush
author_rank: Super Contributor
timestamp: February 13, 2014, 05:43:11 pm
content: There are some resistors and capacitors on the back near the optical isolator. By adjusting those, you can make the power supply change the output voltage slightly.However, it don't think it would be safe to lower the voltage to 5v, it's a bit of a stretch. It would probably be safe to do about 9-14v.smk0760 is a simple mosfet, mbrf20100ct is a common cathode schottky power rectifier 20a maximum, 100v maximum (a bit oversized for this adapter but it's a good thing). Nothing you can adjust.

author: Riotpack
author_rank: Regular Contributor
timestamp: February 13, 2014, 08:46:56 pm
content: You would have to change the number of turns on the secondary of the transformer AND modify the feedback loop to do it properly. Would be easier to add a small high frequency buck converter to the output.

author: rozeh
author_rank: Regular Contributor
timestamp: February 14, 2014, 05:09:09 am
content: Thanks mariush and RiotpackWhat's your opinion about LM2596T-ADJ 3A? for regulate the voltage in output of the power supply?
Help IDENTIFY smd  - Page 1
Forum section: electronics / beginners

author: Daxxin
author_rank: Regular Contributor
timestamp: May 13, 2023, 04:30:12 pm
content: thanksp.s.thats a Lecroy 64xi mobo BCM855LC , power goes on always when plug main cord , someone got same issue?I really wanted to replace with mini-itx coreduo PCI to PC104/+ adapter, can that solution work?

author: DavidAlfa
author_rank: Super Contributor
timestamp: May 13, 2023, 09:13:07 pm
content: Clearly a LDO due the presence of decoupling cap.Measure input/output voltages, probably compatible with hundreds of existing parts.Anyways, does that thing have BIOS? Usually you can configure there what to do after a power loss.

author: Daxxin
author_rank: Regular Contributor
timestamp: May 14, 2023, 03:37:41 pm
content: Thanks , searching by google the most similar code seems thats an NJM78L10A , 10V regulator ..motherboard need 10V for what?

author: gamalot
author_rank: Super Contributor
timestamp: May 14, 2023, 04:16:42 pm
content: https://www.lcsc.com/product-detail/Linear-Voltage-Regulators-LDO_Richtek-Tech_C17366.html
Help for SSD card - Page 1
Forum section: electronics / beginners

author: doubleapril
author_rank: Newbie
timestamp: August 11, 2015, 08:30:29 am
content: My SSD card could not work with my docking station, any help?

author: continuo
author_rank: Frequent Contributor
timestamp: August 11, 2015, 08:40:22 am
content: It may be helpful to include the exact manufacturer/model in your posting...
Help for voltage regulation - Page 1
Forum section: electronics / beginners

author: craziboyi
author_rank: Newbie
timestamp: May 15, 2014, 07:59:20 am
content: Is there any device or component that can clamp the 200V input to 25V for 200mswithout failure? Please help.

author: David Hess
author_rank: Super Contributor
timestamp: May 15, 2014, 02:07:49 pm
content: At what level of current?A transistor can be used to extend the current capability of a simple zener diode clamp circuit.

author: fcb
author_rank: Super Contributor
timestamp: May 15, 2014, 02:20:29 pm
content: Without knowing the current/current profile of the source and more details about the circuit it is pointless question.You could do it with a 1M resistor and a 25v zener... more details required.
Help ID a tantalum cap... - Page 1
Forum section: electronics / beginners

author: whatboy
author_rank: Regular Contributor
timestamp: December 16, 2024, 08:36:59 pm
content: Hello all, I wanna know where can I get this kind of capacitor, the one with the 3 pads (middle one is ground too)... thanks in advance!

author: indeterminate
author_rank: Regular Contributor
timestamp: December 16, 2024, 08:52:26 pm
content: Mouser digikey RS farnell

author: fzabkar
author_rank: Super Contributor
timestamp: December 16, 2024, 09:16:36 pm
content: https://au.rs-online.com/web/p/polymer-capacitors/8663911https://na.industrial.panasonic.com/products/capacitors/lineup/polymer-capacitors/series/79616

author: whatboy
author_rank: Regular Contributor
timestamp: December 16, 2024, 09:20:10 pm
content: I am looking for the 3 PADS one, not the 2...

author: fzabkar
author_rank: Super Contributor
timestamp: December 16, 2024, 09:20:53 pm
content: Quote from: whatboy on December 16, 2024, 09:20:10 pmhttps://na.industrial.panasonic.com/products/capacitors/lineup/polymer-capacitors/series/79616
Help ID Connector - 4 Pins - Page 1
Forum section: electronics / beginners

author: ReedTriesToRepair
author_rank: Contributor
timestamp: March 27, 2023, 10:28:50 pm
content: Wasn't sure what other category this question would fit in, so I put it here.This connector (pictured) came on the back of an ultrasonic power supply and is what is used to connect the probe. I've never seen a connector quite like this before. The plug is recessed about 10mm into the hole. Anyone seen anything like this before? I want to buy the male end to mate with it so it looks as professional as possible (I'm currently sticking jumpers into the holes, not a permanent solution).If it matters, the generator is a Sonics Vibra-Cell VC70.

author: thm_w
author_rank: Super Contributor
timestamp: March 27, 2023, 11:22:42 pm
content: Can you measure the diameter of the inside circle of the black part of the plug?It looks a bit like this but they don't do 4 pin:https://www.ultimateconnector.com/products/circular/micro-circular/micro-circular-solderableWorst case if its not easily purchasable you can make a PCB with some soldered in pins, and glue or 3D print a housing.
Help ID IC -- 1645 S045 2505 - Page 1
Forum section: electronics / beginners

author: u666sa
author_rank: Frequent Contributor
timestamp: December 21, 2024, 02:13:37 pm
content: What is it?

author: fzabkar
author_rank: Super Contributor
timestamp: December 21, 2024, 10:51:39 pm
content: Is there such a thing as a 2:1 RF power multiplexer?MASW-000936-14000T, Macom, PIN Diode SPDT 120 W Switch for 0.05 - 6 GHz High Power Applications, marking yyww+S045+xxxx, PQFN-16:https://cdn.macom.com/datasheets/MASW-000936.pdfhttps://ae-pic-a1.aliexpress-media.com/kf/S6ac6481c0f134d72a050f21a2d1c8a7aO.png(photo)
Help ID smd GL 3787 B1065 - Page 1
Forum section: electronics / beginners

author: u666sa
author_rank: Frequent Contributor
timestamp: June 07, 2025, 04:12:59 pm
content: It's a power chip. Definitely. Something similar to EC chip in laptops. This is on a bluetooth speaker with PIC32MX470F mcu.Markings are GL3787B1065

author: Andy Watson
author_rank: Super Contributor
timestamp: June 07, 2025, 04:22:59 pm
content: https://www.analog.com/media/en/technical-documentation/data-sheets/3787fc.pdf