hybridfree/eevblog-posts huggingface dataset:
Need Help Identifying IC - Page 1
Forum section: electronics / projects

author: rfdes
author_rank: Regular Contributor
timestamp: September 27, 2022, 07:52:15 pm
content: I am hoping someone may be able to identify the semiconductor shown in the photo. It appears to be, possibly, an optical isolated thyristor based on how it is used in the circuit. However, I am not 100% sure. I've done the SMD marking search using some of the online databases with no luck. The SMD package is not recognizable, so if anyone knows the official 'name' of the package that would be helpful.I appreciate your opinions.ThanksJim

author: rooppoorali
author_rank: Regular Contributor
timestamp: September 28, 2022, 04:02:44 am
content: Not sure. Looks a bit like this one:http://www.aosmd.com/res/data_sheets/AOZ5019QI.pdf

author: rfdes
author_rank: Regular Contributor
timestamp: September 28, 2022, 07:30:02 pm
content: Thanks for the input. The IC you mentioned is actually an SMPS part. I am certain that my part is a logic controlled opto-isolated thryistor part as it is used to turn on/off AC 24V relays. It is likely an Asian part and I'm still looking but am on the verge of throwing in the towel.Jim

author: wraper
author_rank: Unknown
timestamp: September 28, 2022, 07:51:03 pm
content: It's made by Monolithic Power Systems, according to marking scheme of their parts, this should be MP5019 but I cannot find such part. Sometimes part number may have additional letters after MP, but MPS website search does not find any part with 5019 number anyway.

author: wraper
author_rank: Unknown
timestamp: September 28, 2022, 08:01:23 pm
content: Overall MP50xx devices have similar packages and are mostly power switches/current protection devices. I really doubt this part can work with AC.https://www.monolithicpower.com/en/catalogsearch/result/index/?p=2&q=mp50Also it's certainly not how optoisolators look, they have a large gap between input and output. Not a bunch of terminals all around.

author: wraper
author_rank: Unknown
timestamp: September 28, 2022, 08:07:08 pm
content: Even though there is no data, MP5019GQV does existhttps://www.avnet.com/shop/us/products/mps/mp5019gqv-z-3074457345634952895/

author: rfdes
author_rank: Regular Contributor
timestamp: September 28, 2022, 09:36:58 pm
content: Quote from: wraper on September 28, 2022, 08:07:08 pmWell... thanks a bunch. At least I've got a start. I also reviewed the MPS website and agree with your assessment that the part matches their marking.The part is used several times in a Honeywell Programmable thermostat. I've verified that the part is used as an AC SSR with a digital control input. I am wondering if this is a custom part made for the thermostat mfg. I think I will reach out to MPS and ask their support engr for some information.I appreciate your research.Take care -Jim

author: gamalot
author_rank: Super Contributor
timestamp: September 28, 2022, 10:02:48 pm
content: Here are some pictures from Chinese sellers.
Need help identifying oddball ICs - Page 1
Forum section: electronics / projects

author: Devicemodder
author_rank: Newbie
timestamp: September 18, 2023, 02:43:18 am
content: I need to identify some ICs in an old calculator I am repairing. It's a Unitrex 1200 from 1972, and the ICs in question are:5312, 6259, 6225.

author: ataradov
author_rank: Super Contributor
timestamp: September 18, 2023, 03:02:31 am
content: HB indicates that it is not an IC, but a hybrid assembly. In this case I'd guess they contain diodes or transistors.There is very slim chance of finding a replacement. Your best bet would be to document how they are used in the circuit and possibly recreate them from discreet elements.

author: Devicemodder
author_rank: Newbie
timestamp: September 18, 2023, 03:14:50 am
content: >HBthat's what i kinda figured. the 6225's are driving a panaplex display, and are coupled to the MOS IC via capacitors.
Need help identifying radio smd component   - Page 1
Forum section: electronics / projects

author: Garry2
author_rank: Newbie
timestamp: March 29, 2015, 04:43:27 pm
content: This board is located on the 2.4ghz cable going the the antenna. it is for a quadcopter controller the sends control data and receives telemetry data. Someone said that it was an attenuator to make it ce compliant. The problem is that I have seen it on all versions of the controller including ones shipped to the US. To me it looks like some kind of filter. The back side of the board says UPG2520 v2.

author: SeanB
author_rank: Super Contributor
timestamp: March 29, 2015, 04:54:43 pm
content: SMD bandpass filter, designed to attenuate out of band emissions so it will be compliant with EMC regulations. They probably should have put this on the main board, but did not want to respin it ( or had too many already made when they went for EMC approval) when it failed EMC compliance, so the filter was a quick fix instead.

author: Garry2
author_rank: Newbie
timestamp: March 29, 2015, 04:58:19 pm
content: Thank you, that's what I thought. So this would not likely be used to reduce the overall power output, just filter extra emissions?

author: SeanB
author_rank: Super Contributor
timestamp: March 29, 2015, 05:06:22 pm
content: Should have very little effect on power output ( might give 1cm extra range if removed, but the cellphone in your pocket will then decrease range by about half then from it's radiation) and helps the receiver to only have to handle in band signals.

author: embeddedbob
author_rank: Contributor
timestamp: March 29, 2015, 05:07:49 pm
content: It looks like a Walsin filter (2.4GHz bandpass); I have used one in my current 2.4GHz design. It will be used to supress out of band emissions.http://www.mouser.com/ds/2/210/RF_ProductCatalog_Feb08-5244.pdf
Need help identifying SMD component - Page 1
Forum section: electronics / projects

author: Lomax
author_rank: Frequent Contributor
timestamp: September 04, 2022, 09:12:21 am
content: I can usually help myself with this stuff, but this time I am stumped. Metal package 7.5x5.5mm with two legs, marking is "030 VJ9F". I think I recognise the logo, but can't remember what brand it is. Web searches turn up nothing.

author: gamalot
author_rank: Super Contributor
timestamp: September 04, 2022, 09:30:57 am
content: Littlefuse SMD030-2https://www.micro-semiconductor.com/datasheet/4d-SMD030-2.pdf

author: Lomax
author_rank: Frequent Contributor
timestamp: September 04, 2022, 09:43:51 am
content: Fantastic, thank you! Was it the logo?

author: gamalot
author_rank: Super Contributor
timestamp: September 04, 2022, 11:01:01 am
content: Quote from: Lomax on September 04, 2022, 09:43:51 amYes, Littelfuse is a very common fuse brand.

author: tooki
author_rank: Super Contributor
timestamp: September 04, 2022, 11:29:03 am
content: But that’s not the Littelfuse logo. The datasheet you linked is an old one from before Littelfuse bought the polyswitch product line from TE (and is in fact old enough to list it as Tyco, not TE). Littelfuse still puts that logo on the product, but whose logo (or, as the datasheets call it, “manufacturer’s mark”) is it?

author: gamalot
author_rank: Super Contributor
timestamp: September 04, 2022, 11:53:06 am
content: Quote from: tooki on September 04, 2022, 11:29:03 amI really don't know where Tyco Electronics got this logo, but we all know it's so popular that Littelfuse is still willing to keep it on products.
Need help identifying test ports - Page 1
Forum section: electronics / projects

author: jdak907
author_rank: Contributor
timestamp: May 02, 2018, 08:01:18 pm
content: Hi All,Can someone help me identify these test ports? (image attached) They are from a circa 1984 Dolby CP65 digital cinema processor. The port diameter is around 3/32".Is there a standard name or package description for these? I am trying to hunt down the male end connector for this port so I can make some patch cables.After searching online the best I can come up with is they are maybe some type of banana connector jack..Thanks!Jeff

author: calmtron
author_rank: Regular Contributor
timestamp: May 02, 2018, 08:13:46 pm
content: 2mm banana plugs perhaps?https://www.digikey.com/product-detail/en/cinch-connectivity-solutions-johnson/105-0752-001/J109-ND/5887

author: jdak907
author_rank: Contributor
timestamp: May 02, 2018, 08:43:29 pm
content: That's it.Thank you!
Need help identifying the chip(14285-002 PANDORA II PLCC52 ON) - Page 1
Forum section: electronics / projects

author: daisizhou
author_rank: Super Contributor
timestamp: September 15, 2021, 11:38:41 am
content: Hello everyone,Can anyone find the information or data sheet of this chip?This is a chip related to the ECG signal, I want to know the definition and work of the pin

author: Benta
author_rank: Super Contributor
timestamp: September 15, 2021, 07:07:38 pm
content: Well, it's from ON semiconductor , today onsemi.It might be a support chip for an Aptina image sensor (onsemi acquired Aptina in 2014). But that's just a vague hypothesis.

author: daisizhou
author_rank: Super Contributor
timestamp: September 15, 2021, 11:42:21 pm
content: Yes, I did not find more information
Need help identifying these transformers.. - Page 1
Forum section: electronics / projects

author: shamooooot
author_rank: Regular Contributor
timestamp: July 07, 2023, 04:27:17 am
content: Hello guysI am struggling to find what transformers are these , and I don't even know where to start as all the resources I found didn't get to mention them!.1- T2 and T3 in this Push-pull amplifier with double final stage circuit:2- T1 Transformer-Coupled Amplifier circuit:3- L1 in Hartley generator circuit:4- T1 in Astable multivibrator:5- T1 in AM circuit which is different from the above 4:

author: Kim Christensen
author_rank: Super Contributor
timestamp: July 07, 2023, 05:01:00 am
content: Those above are old school audio transformers that were used in transistor radios in the 1960's and 70's. They'll be hard to find today.Though I did findsome on mouser.I believe the red output one (T3 in Push-pull amplifier OPT) is a 42TL013-RC. T2 (IPT) is probably a 42TL002-RC.This another transformer (Probably 455Khz IF) that was also used in old radios.Is there any reason you want to build these old circuits? You can get better audio amps on a single IC these days. Or build a different transformerless design.

author: shamooooot
author_rank: Regular Contributor
timestamp: July 07, 2023, 05:29:05 am
content: I appreciate your reply Kim..Actually I am building these PCB's for educational purposes for the students.Are there common values for these transformers or is there a way to find out their parameters. We can create these transformers if they aren't available anymore.

author: Kim Christensen
author_rank: Super Contributor
timestamp: July 07, 2023, 05:33:15 am
content: T3 in Push-pull amplifier might be a 42TL013-RC. T2 (IPT) is probably a 42TL002-RC. See my edit (Mouser link above)

author: xavier60
author_rank: Super Contributor
timestamp: July 07, 2023, 12:08:35 pm
content: Assuming the transformers are found, the biasing for Q5 might have trouble.

author: Kim Christensen
author_rank: Super Contributor
timestamp: July 07, 2023, 06:56:16 pm
content: Dug upa bit more info on old IF transformers.Since they show (C9 47pF) in the AM circuit diagram. It's probably one without a built in capacitor such as the 42IF104. Though you could use a 42IF101 or 42IF301 if you eliminated C9.In the end, I think you're just going to have to buy some samples from Mouser and build the circuits to verify that they work as intended and that you've got the right parts. Then order enough for your students. Or find a site that gives you better info about the parts used in their circuits. Where did you find those diagrams anyway?

author: xavier60
author_rank: Super Contributor
timestamp: July 07, 2023, 09:00:12 pm
content: This AM receiver kit has audio transformers,https://www.aliexpress.com/item/1005004064556135.html?spm=a2g0o.productlist.main.91.642d6205Izj7hS&algo_pvid=ea05f3fb-c71b-4572-8874-84137b5dd894&algo_exp_id=ea05f3fb-c71b-4572-8874-84137b5dd894-45&pdp_npi=3%40dis%21AUD%219.31%218.56%21%21%216.08%21%21%40210219c216887633155036858d073a%2112000027917991635%21sea%21AU%21130254308&curPageLogUid=YDt0Q0t3lbSM
Need help identifying this connector (pics included) - Page 1
Forum section: electronics / projects

author: andyg
author_rank: Regular Contributor
timestamp: April 19, 2020, 04:23:27 pm
content: Hello,Does anyone know what type of connector this is? I've tried looking at the usual places I buy components without any luck, although I'm not really sure what this is categorised as. It's a through hole connector which takes a approx 0.7mm square crimp male pin, pushed in horizontally to the PCB. Thanks.

author: bob91343
author_rank: Super Contributor
timestamp: April 19, 2020, 05:22:33 pm
content: It appears to be a custom made device made from eyelets put into some insulation stuff. You can make one yourself.

author: edba
author_rank: Contributor
timestamp: April 20, 2020, 07:46:07 pm
content: Looks like a horizantal side entry female header, where they have just cut a example a 10 row connector into individual connectors. Pls see link below:https://www.e-tec.asia/products/board-to-board-wire-to-board-connectors/female-header.html

author: andyg
author_rank: Regular Contributor
timestamp: April 21, 2020, 05:38:05 am
content: Quote from: edba on April 20, 2020, 07:46:07 pmThanks @edba - that looks about right!

author: WattsThat
author_rank: Frequent Contributor
timestamp: April 22, 2020, 07:02:53 pm
content: Sure looks like the business end of a Pace SX-70 TH desoldering tool. The board looks pretty toasty, hope you can repair without the board crumbling. If not, the entire assembly can be had (for a price).http://www.techni-tool.com/612PA098

author: andyg
author_rank: Regular Contributor
timestamp: April 24, 2020, 01:41:47 am
content: Quote from: WattsThat on April 22, 2020, 07:02:53 pmThanks. Good recognition, TJ-70 hot air pencil to be exact. Almost identical.
Need Help Identifying This IC - Page 1
Forum section: electronics / projects

author: Guitarfreak302
author_rank: Newbie
timestamp: June 05, 2024, 09:36:56 am
content: I am trying to ID this IC so I can repair this circuit board. The IC is intact in the picture but it now has some leads missing. The circuit is from a Clarion marine radio external remote. The remote is wired not wireless. The remote model is CMRC3D. It is now removed from the board and is supposed to go where it is labeled U2. I included a very crude schematic of what I traced out so far. Looks like GND is on pin 1 and power is pin 20. Your help would be appreciated. Thank you.Ryan

author: ondraN
author_rank: Regular Contributor
timestamp: June 05, 2024, 10:44:01 am
content: It looks like some MCU. It probably won't replace it because you don't know its internal microcode.

author: Guitarfreak302
author_rank: Newbie
timestamp: June 05, 2024, 12:33:51 pm
content: Thanks for the reply. I thought it looked like a MCU too but was curious which one it could be.

author: moffy
author_rank: Super Contributor
timestamp: June 05, 2024, 12:56:36 pm
content: Quote from: Guitarfreak302 on June 05, 2024, 12:33:51 pmI thought maybe a bit more like a serial keyboard encoder, similar to:https://ece-classes.usc.edu/ee459/library/datasheets/ede1144.pdfThe keys look like they are scanned in a matrix and the data is sent serially out Remocon on CN2. It might help to see what the chip is that receives the data, if it is a dedicated receiver chip.

author: Guitarfreak302
author_rank: Newbie
timestamp: June 05, 2024, 06:51:22 pm
content: The chip that receives the data is a M30622MEP which is a 16 bit MCU. Remocon connects to pin 4 which is labeled as P9_1/TB1IN/SIN3.

author: moffy
author_rank: Super Contributor
timestamp: June 05, 2024, 10:07:40 pm
content: Quote from: Guitarfreak302 on June 05, 2024, 06:51:22 pmSIN3 might mean 'Serial In 3', which would be a UART, so it looks like the encoder might be sending the key data via a logic level RS-232 serial data stream.According to the brief data sheet it looks like the M30622 has 3 UARTs:https://www.renesas.com/us/en/document/dst/m16c62p-group-m16c62p-m16c62pt-datasheet

author: Guitarfreak302
author_rank: Newbie
timestamp: June 06, 2024, 04:17:56 am
content: That actually makes sense now. Thanks
Need Help Identifying this Part (Zener Diode) - Page 1
Forum section: electronics / projects

author: bigwave
author_rank: Newbie
timestamp: November 03, 2024, 06:41:35 am
content: This little fella (D1 in the attached diag.) marked "33 8J" was installed between Vcc=3.3v and an IR photo sensor (QRE1113) output using a 51k pull-up resistor. Output feeds a GPIO pin input on a Nordic-semi SOC module. It's probably a 3.3v zener but it would be good to know for sure. I hunted for the symbol and codes but was unsuccessful - maybe "F" for "Fairchild"?. D2 is a lot smaller and both seem just for transient and input protection. [It's off a Wahoo Kickr Core trainer, if you're curious].Thanks,Dave

author: ArdWar
author_rank: Frequent Contributor
timestamp: November 03, 2024, 07:02:45 am
content: LF for Littelfuse, they're well known for making circuit protection so it's very likely a TVS diode.Although considering the implementation I wonder why are they using TVS there, and using it in such way. Feels like rather weird even for a bodge.

author: floobydust
author_rank: Super Contributor
timestamp: November 03, 2024, 08:03:58 am
content: I find it as Littelfuse TVSSMF3.3a 3.3V clamp, with no capacitance spec. relevant to the high value 51k resistor in your circuit. Not sure of the speeds here.There may be ESD discharges with a moving wheel and this is for coverage.

author: bigwave
author_rank: Newbie
timestamp: November 03, 2024, 04:19:33 pm
content: Quote from: ArdWar on November 03, 2024, 07:02:45 amThanks. I thought it a bit odd as well. The sensor is on a pigtail about 6cm away from Zeners on the main board-- I thought maybe they had some spurious power supply injection during testing -- this trainer has a pretty beefy stator with the sensor nearby.-Dave

author: bigwave
author_rank: Newbie
timestamp: November 03, 2024, 04:36:21 pm
content: Quote from: floobydust on November 03, 2024, 08:03:58 amThanks! Yah, quite possibly it's for discharge given the proximity to the back-emf stator (maybe inductive noise) -- sample rate is less than 2kHz. The 51k does not seem typical for this sensor - the few other sensor projects I've seen using this BJT photocell typically use 10k with the LED biased at 100 ohm. (you can buy the thing from sparkfun with/without a cap. I think the larger collector resistance is there to drive down Vce and put the zero (low) side value closer to ground. The pin-out for the soc gives Vzero-Digital as up to .3xVcc max (3.3v).-Dave[I miss through-hole! :-) ]
Need Help Identifying this Part - Page 1
Forum section: electronics / projects

author: robson2017
author_rank: Contributor
timestamp: November 06, 2024, 10:29:04 am
content: Hello everyone,I'm looking for a part number and name/type of package.Thanks,Robpart1.jpg(12.95 kB. 333x181 - viewed 26 times.)

author: electronx
author_rank: Regular Contributor
timestamp: November 06, 2024, 11:23:14 am
content: Hey Rob, If you take photos of the part under different angles and lighting, we can see sharper text. Also, if you tell us what the device is, it will be easier to classify it in the component ecosystem.

author: electronx
author_rank: Regular Contributor
timestamp: November 06, 2024, 11:27:01 am
content: package is looking like DFN-2510-10mostly used in esd protection diodes (?)(not sure)Is it positioned close to the I/O of the pcb ? For example HDMI or HDMI,DisplayPort, eSATA and LVDS or usb?

author: robson2017
author_rank: Contributor
timestamp: November 06, 2024, 11:57:51 am
content: Hello electronx.Yes, it's located near the component input/output.I don't have the pcb on my desk to take a better picture but this info is enough to replace this component.Thanks,Rob

author: electronx
author_rank: Regular Contributor
timestamp: November 06, 2024, 12:05:02 pm
content: Vrwm should be above maximum operating voltageplease pay attention to the operating voltage of the relevant input output unit.also don't forget to evaluate the emc factors.i found something like this for h series but i'm not sure if it's the same manufacturerregards

author: robson2017
author_rank: Contributor
timestamp: November 06, 2024, 12:09:16 pm
content: I will, thank you.Rob.
Need help IDing a 12.7mm 2-pin round connector... - Page 1
Forum section: electronics / projects

author: philpem
author_rank: Frequent Contributor
timestamp: September 05, 2018, 09:30:27 pm
content: Hi,I'm trying to find a mating plug for the power connector on a data radio (a Maxon DM200; power cable part number ).The radio-side connector is male (has pins) -- so the mating cable-side connector would have to be female.The external thread diameter at the radio side is 12.7mm, with a threaded length of only 3.5mm.There are two pins. The left pin has a diameter of 1.5mm, while the right has a diameter of 2mm. This is the only keying on the connector - the pin size difference.The pins are approx. 4mm centre-to-centre.I've found a picture of the connector (plugged into the radio), which I've attached.Does anyone recognise this thing?ThanksPhil.(EDIT 2018-09-06 to add photo of the front of the connector, oops)

author: amyk
author_rank: Super Contributor
timestamp: September 06, 2018, 01:41:43 am
content: How do you expect us to identify the thing if we can't even see the pins? A better picture would help greatly.

author: Bratster
author_rank: Frequent Contributor
timestamp: September 06, 2018, 05:07:17 am
content: Definitely need a picture of the face of the connector to really be of any help...But from what is shown it kind of looks like something along these lines:https://uge-one.com/aviation-plug-2-pin-16mm-gx16-2-male-and-female-panel-mounted-metal-connector.htmlSent from my Fi Moto x4 using Tapatalk

author: philpem
author_rank: Frequent Contributor
timestamp: September 06, 2018, 06:38:43 am
content: Oops! I knew I'd forgotten to attach something!Photo of the face of the connector attached. You can see that one pin is slightly smaller.(The other connector is the TNC antenna connector)I've looked at the GX16, but it's polarised with a notch, like a DIN plug. This strange thing seems to use the pin sizes for keying, and possibly the pin position (they're slightly off-centre in the "up-down" direction)

author: philpem
author_rank: Frequent Contributor
timestamp: September 06, 2018, 09:57:21 pm
content: I've got some more (better!) photos of the connector.All the plastic parts are green.The panel hole appears to be 12mm diameter, with a rubber or foam washer between the connector surround and the panel. The mounting nut is one of those round ones which needs a pin spanner to remove. A bit like the ones Lumberg use on their locking DIN connectors. Pins are numbered on the back.Oh, and it has a logo on it. A "W" in a circle?

author: philpem
author_rank: Frequent Contributor
timestamp: September 19, 2018, 04:39:10 pm
content: Right then, I reckon this mystery's solved (or solved enough for me).Talked to the company who took over support for the radio manufacturer last night. It's apparently a custom made connector (!) and the cables are £50 each, plus postage, plus VAT, with a several week lead time!So in the true spirit of bodgery, I stripped the thing to bits and replaced the connector with a GX12-2 "aviation connector". Added fresh cable (mmm, silicone wire!) and a PowerPole and now I have a working Mobitex radio to play with!
Need help IDing this connector - Page 1
Forum section: electronics / projects

author: Kjelt
author_rank: Super Contributor
timestamp: April 15, 2015, 05:03:36 pm
content: I can not seem to find the manufacturer and series of this connector, I need a couple of female connectors to connect to this one, anyone know this and can ID this connector?Thanks

author: Kjelt
author_rank: Super Contributor
timestamp: April 15, 2015, 06:00:16 pm
content: Just got a email that it might be the JST PA series.... hmmmm they look alike but still there are some sublte differences.The pin pitch is correct.Other dimensions are not given in the datasheetCan order some to see if they fit.
need help in designing for the power supply for a development board - Page 1
Forum section: electronics / projects

author: me.rishabh12
author_rank: Contributor
timestamp: April 05, 2018, 05:35:27 pm
content: hii allim designing a microcontroler development board and it use some 5v and some 3.3 v peripheralsit contain a stm32f407 144pin microcontroller and ethernet,wifi,rs485,usb,eeprom,sd card,couple of ledsin addition to that i will also design couple of stackable boards like relay module and optoisolated input and otherpls suggest that i should use a switching regulator for 3.3 and 5v or i design a 5 v switching and ldo for 3.3v

author: KhronX
author_rank: Frequent Contributor
timestamp: April 05, 2018, 05:59:53 pm
content: That's a bit vague...What will the current requirements be, for the 5v and 3.3v rails? And what input voltages will you be expecting?

author: CopperCone
author_rank: Super Contributor
timestamp: April 05, 2018, 06:53:33 pm
content: Should be built for the maximum current draw of the MCU as specified by the datasheet and then a bit overI would make a spreadsheet of the absolute maximum current of each device on your PCB.

author: me.rishabh12
author_rank: Contributor
timestamp: April 06, 2018, 07:27:13 am
content: input volts can be from 6 to 24 vdcand it can also be powered from usb
Need help in Filter design for SPWM Inverter - Page 1
Forum section: electronics / projects

author: radhika
author_rank: Regular Contributor
timestamp: June 27, 2020, 04:41:44 pm
content: Hello,I am working on some SPWM 24V DC to 220V 400HZ AC output.I have used PIC microcontroller and generate 400Hz SPWM. I have used H-Bridge and to AC wave. But actually this is what not I am getting.Problems I am facing:1. The frequency fluctuates much.. From 350Hz-750Hz, though I got SPWM.2. Their is lot much noise which I am getting at H-Bridge side. I am using IR2110 driver and IRL540 MOSFET.Here is the Schematic:https://postimg.cc/Zvhb6R40Here is the wave which I got when I check it on real breadboard at an h bridge output:https://postimg.cc/gwXm5R0nI want to get Sine wave, I am unable to get right filter for the same.Can any one help me.Thanks in Advance.

author: radhika
author_rank: Regular Contributor
timestamp: June 27, 2020, 06:52:47 pm
content: Anybody?'Awaiting.

author: Benta
author_rank: Super Contributor
timestamp: June 27, 2020, 08:57:17 pm
content: You're showing us only the power stage with drivers. From what I can see it corresponds to the IR2110 datasheet recommendations. So that's OK (but do a double-check, OK?).1: If you are building this on one of those plastic-blob-with-spring-connectors so called "breadboards" you'll never get it to work. You really need to make a proper prototype PCB with nice routing. It's not expensive these days.2: If your sine-wave frequency is not rock-steady at 400 Hz, it's a problem in your PIC firmware.Good luck.

author: radhika
author_rank: Regular Contributor
timestamp: June 28, 2020, 07:27:54 am
content: Okay.Here is the code for SPWM:Code:#include <xc.h>#define _XTAL_FREQ 20000000unsigned char sin_table={0,2,4,7,9,11,12,14,15,16,17,18,18,18,18,17,16,15,14,12,11,9,7,4,2};unsigned int TBL_POINTER_NEW, TBL_POINTER_OLD, TBL_POINTER_SHIFT, SET_FREQ;unsigned int TBL_temp;unsigned char DUTY_CYCLE;void interrupt tc_int (void){if (PIR1bits.TMR2IF == 1){TBL_POINTER_NEW = TBL_POINTER_OLD + SET_FREQ;if (TBL_POINTER_NEW < TBL_POINTER_OLD){CCP1CONbits.P1M1 = ~CCP1CONbits.P1M1; //Reverse direction of full-bridge}TBL_POINTER_SHIFT = TBL_POINTER_NEW >> 12;DUTY_CYCLE = TBL_POINTER_SHIFT;CCPR1L = sin_table;TBL_POINTER_OLD = TBL_POINTER_NEW;PIR1bits.TMR2IF = 0;}}void main() {SET_FREQ = 205;TBL_POINTER_SHIFT = 0;TBL_POINTER_NEW = 0;TBL_POINTER_OLD = 0;DUTY_CYCLE = 0;ANSEL = 0; //Disable ADCCMCON0 = 7; //Disable ComparatorPR2 = 24;TRISC = 0x3F;CCP1CON = 0x4C;PIR1bits.TMR2IF = 0;T2CON = 4; //TMR2 on, prescaler and postscaler 1:1while (PIR1bits.TMR2IF == 0);PIR1bits.TMR2IF = 0;TRISC = 0;PIE1bits.TMR2IE = 1;INTCONbits.GIE = 1;INTCONbits.PEIE = 1;while(1);}But, also, I want to design filter which will place just after the H-Bridge. I gone through with many article and research paper, but I am unable to find right L.C.R value. Can someone help me?
Need help in replicating a "SPICE" program - Page 1
Forum section: electronics / projects

author: zythious
author_rank: Newbie
timestamp: January 18, 2022, 01:10:25 pm
content: Hello,I'm interested in creating a simple "SPICE" program. Let me begin by trying to illustrate what I've done so far.During my bachelor thesis, I wrote a program to simulate a pre-defined circuit in MATLAB using the Modified Nodal Analysis(MNA). My reason for using MNA is that it can isolate all unknown voltages and currents in one matrix, making it very convenient when obtaining those parameters. It's more complicated than the usual Mesh and Nodal Analysis, but it's much systematic, which is very program friendly.Now, I am interested in working on a project that will try to solve a circuit set up in a grid-like pattern. Its components are just resistors and voltage sources. The tricky part is the components arenot pre-defined; the components will be"randomized"in the grid. Some resistors may be disregarded as they may be floating. I will be attaching what it could look like.In the picture, it's 3D, but I will start first with 2D, where it'll be simpler. I know creating a netlist and solving it using a SPICE program could just do the trick. However, the randomization aspect makes it impractical for each instance. I'm hoping to create such an "algorithm" that can take the randomized setup of the components and solve a givennbyncircuit. I already have an idea on how to do it, but I just want to hear some thoughts; perhaps recommend a better circuit analysis method suited for this problem. For now, I will be considering the ideal scenario where it follows Ohm's law.Thanks.

author: sclafa
author_rank: Newbie
timestamp: January 18, 2022, 03:11:49 pm
content: It seems like you could use the usual techniques to assemble the modified nodal analysis (MNA) matrices for arbitrary circuits.http://qucs.sourceforge.net/tech/node14.html

author: Terry Bites
author_rank: Super Contributor
timestamp: January 18, 2022, 04:11:33 pm
content: Chew on this:https://www.slideshare.net/JihadHAsad/24-infinite-3-d-cubic-lattices-of-identical-resistors
Need help in simulation of a mini project using piezoelectricity  - Page 1
Forum section: electronics / projects

author: Jeffrey1627
author_rank: Newbie
timestamp: January 30, 2024, 11:13:23 am
content: Hello everyone.I have a small project about piezoelectricity but Im a little stuck and don’t have enough time. My project is about studying the potential vibration control in a tennis racket using piezoelectric materials. The piezo role is to detect the vibrations then it will turn it to electrical signal, then it will get recaptured and by a microcontroller, the piezos will get enough voltage to then vibrate in the opposite way in order to cancel the vibrations immediately.Now, I want to do a simulation of all this because it’s just hard for me to do it manually at home, but I don’t know what software to use and how to do it, idk even if it’s feasable and I need help.

author: DTJ
author_rank: Super Contributor
timestamp: January 30, 2024, 01:59:19 pm
content: What frequencies do tennis racquets vibrate at after hitting a ball?Would you start there first?I don't know but imagine the frequencies are all sub 15kHz or thereabouts. Would destructive ultrasound frequencies work?How much power would you need to dampen the string vibration and how fast would you want it to happen?I may be wildly wrong but this is my guess at an approach.

author: Jeffrey1627
author_rank: Newbie
timestamp: January 30, 2024, 02:07:59 pm
content: I appreciate the reply! I have a project that I should do as a uni assignment and I found this one very interesting and already fixed, so I can’t really do another project or even change the approach of this study. I just need a software that can simulate this happening like in real life, then I will get real data from the software about the different vibrations that were canceled and how fast the response was for each one.

author: moffy
author_rank: Super Contributor
timestamp: January 30, 2024, 10:03:55 pm
content: It is a mechanical system, the racket, you would need to model the racket frame if not also the strings in a mechanical CAD simulation package. How to do that accurately would require significant effort. The piezos would almost be an after thought compared to the racket.
Need help locating source for resistive strain guage pointing device - Page 1
Forum section: electronics / projects

author: rfdes
author_rank: Regular Contributor
timestamp: January 31, 2019, 01:09:37 am
content: Hi -I am having a devil of a time finding a vendor that sells the small pointing device that is used on some laptop keyboards that function much like a mouse. They (or so I understand) use the the method of resistance strain gauge to implement this function. Many laptops still have these devices embedded into their keyboards but damn if I can find a vendor. CTS use to sell them but have ceased production. Supposedly ALPs also sold these but I can find no reference on their website.If anyone could point me to where these devices can be sourced, I would certainly appreciate it. My lack of hits while searching may be partly due to the fact I don't ever know for sure what these devices are commonly called.Any help that you can offer would be most appreciated.ThanksJim

author: timpattinson
author_rank: Contributor
timestamp: January 31, 2019, 01:43:18 am
content: also known as 'trackpoint', 'nipple mouse'

author: rfdes
author_rank: Regular Contributor
timestamp: January 31, 2019, 11:26:43 am
content: Yes, thanks for the response.I am trying to find a source to redesign a legacy keyboard that uses these input devices. They supposedly still exist but are very hard to find. Most vendors have stopped selling them it appears.Take care -Jim

author: LapTop006
author_rank: Unknown
timestamp: January 31, 2019, 11:30:44 am
content: Quote from: timpattinson on January 31, 2019, 01:43:18 amObligatory XKCD:
Need Help: Looking for Realtek RTD2801VPF Datasheet – Willing to Pay - Page 1
Forum section: electronics / projects

author: lavi1113
author_rank: Newbie
timestamp: December 04, 2024, 05:25:53 am
content: Hi everyone,I’m an entrepreneur working on a startup with a unique product idea, and I’m planning to use the Realtek RTD2801VPF chip as a key component for a new type of capture card. However, I’ve run into a brick wall trying to get the datasheet for this chip.I’ve reached out to Realtek directly, but they declined my request, saying my project isn’t “interesting enough” at this stage. I’ve also tried searching online, called suppliers in China, and exhausted all the obvious options, but no luck. I believe this chip could be perfect for my product, and I’m determined to make this work.If anyone has access to the datasheet or knows someone who can help me get it, I’m more than happy to compensate you for your time and effort.To clarify:I’m not looking to misuse the information or breach any laws. I just need to evaluate the chip for my product before making a significant investment in development.If the chip checks out, I’m prepared to take further steps, including traveling to Realtek offices to negotiate a supply agreement.If you can help or know someone who might be able to, please reach out or comment below. This means a lot to me, and I’m eager to move forward with this project.Thank you in advance! 🙏

author: coromonadalix
author_rank: Super Contributor
timestamp: December 04, 2024, 05:44:46 pm
content: no offence, but you should tell here, you have posted on other sites and received some answers ... Redditeven under nda as others wrote, you may never get it .. this chip is used in audio video stuff and maybe it can brake the hdmi signal protection ... that could be the reason you wont get any more infos ...https://aphnetworks.com/reviews/avermedia-live-gamer-4k-2-1-gc575/2try some dedicated forums on audio video capture ...even with good intentions, it may sound like reverse engineering and maybe some dark use(s) ...

author: amyk
author_rank: Super Contributor
timestamp: December 05, 2024, 02:47:58 am
content: Given that there's a total of one or two products using this SoC, I suspect it may be a customer-exclusive design. If you're really determined, try to find someone at that customer who may be willing to tell you more.
Need help measuring current for very short bursts, Lower North Island, NZ - Page 1
Forum section: electronics / projects

author: foufee
author_rank: Newbie
timestamp: June 14, 2016, 03:07:11 am
content: We have a small transmitter that we want to measure how much current it uses per time it runs, I was wondering if anyone on here would be kind enough to assist us in measuring the current over time using a OScope current probe, we've looked at buying one, but they aren't cheap!We're situated in the Lower North island in New Zealand.Thanks in advance.Matthew

author: tautech
author_rank: Super Contributor
timestamp: June 14, 2016, 03:27:34 am
content: Welcome to the forumWhat current are you needing to measure?Mains?Couldn't a logging DMM do that?I've not any planned trips down your way but I have some tools that could probably help.

author: foufee
author_rank: Newbie
timestamp: June 14, 2016, 03:33:03 am
content: Thanks...The current is below 100mA, and the event lasts for less than 1s. We have a logging DMM but the sample rate is too slow. I've got a DS1054Z that we were thinking of using if we could find a probe.

author: tautech
author_rank: Super Contributor
timestamp: June 14, 2016, 03:41:51 am
content: Quote from: foufee on June 14, 2016, 03:33:03 amIs it AC or DC?Thinking simple current shunt and if you need isolation from mains Gnd use a differential measurement with 2 channels. Jaycar QP-5140 might do the job.Unless I'm missing something this should be very simple with a DSO, use a single shot and appropriate channel attenuation and trigger settings.

author: foufee
author_rank: Newbie
timestamp: June 14, 2016, 04:00:17 am
content: DC, awesome, thanks for the pointer, certainly cheaper than a current probe for the scope!

author: tautech
author_rank: Super Contributor
timestamp: June 14, 2016, 04:08:49 am
content: Quote from: foufee on June 14, 2016, 04:00:17 amMight have a spare P6021 soon, use a PM or contact links in my website if you're interested.
Need help on battery protection/charger project - Page 1
Forum section: electronics / projects

author: yannickg
author_rank: Newbie
timestamp: March 06, 2020, 05:08:04 pm
content: Hi, I hope I'm not asking too much but I'm really stuck on this project and need help from a more experienced person.I have a single 18650 Li-Ion cell that I'm trying to protect with the AP9101 chip and also charge with the MAX1555 chip. Here's my schematic, I checked and rechecked everything and I can't seem to make it work. Right now I'm unsure about how I interconnected the two ICs, maybe it's all wrong from the start...Any input is welcomed and thanks!!!

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 06, 2020, 05:42:31 pm
content: One obvious mistake is that you connected the global GND both to the battery's neg terminal and to the external DC source neg terminal, which doesn't make sense, it will just make the protection IC useless and probably confuse it enough to cause it not to work.

author: yannickg
author_rank: Newbie
timestamp: March 06, 2020, 08:38:04 pm
content: Schematic mistake, sorry about that. The DC ground is actually connected to P-. Would that be right?I updated the schematic.

author: norand
author_rank: Contributor
timestamp: March 08, 2020, 02:12:37 pm
content: Without a proper look, few things I have noticed:The *POK/*CHG line is an open drain, and hence your LED2 is connected the wrong way round (see attached image). You may also want to tie it to your external 5V source as oppose to your Lithium ion cell, so the power comes from the source and not the battery.Quote from: yannickg on March 06, 2020, 08:38:04 pmYes this is correct, but I don't see the change in SCH?It would also be worth checking your cell voltage, and making sure it isn't below the deep discharge threshold.When you say:Quote from: yannickg on March 06, 2020, 05:08:04 pmIt would be better to describe what part is not working, what parts have you measured to verify it is nor working etc. Hard to help you when there is little informationHope this helps.
Need help on flyback converter. - Page 1
Forum section: electronics / projects

author: blueskull
author_rank: Unknown
timestamp: January 21, 2015, 08:26:18 am
content: Hi guys,I've be debugging my power supply project for a while, and tonight (maybe morning now, my local time is 3:14 am) I finally got it worked (only the flyback stage, for more info pls check out my usb mini power supply topic).The efficiency data is pretty nice, I've got a 91.5% yield. However, the drain waveform is very, very disturbing, pls see the attached files.The problem is NOT on oscilloscope grounding or MOSFET gate waveform, I doubled checked them, and they are just fine.Generally you expect the voltage goes down when MOSFET turns on, then the voltage goes up to flyback output voltage/turn ratio (2 in this case), then when all energy in the inductor was depleted (I operate this thing in DCM), the voltage should go back to supply voltage.I can understand there will be some sort of ringing overshoot, but the waveforms shows huge ringing undershoot, which I can not explain it using my knowledge.The switching frequency is 800 kHz (precise value is 798.18 kHz), and the primary inductance without bias current is somewhere around 2.7 uH measured with smart tweezers st-5s at 10 khz, 0.9 vrms setting.I can observe NO significant voltage fluctuation on both MOSFET source and supply voltage (I measured directly in the transformer's solder joint).Any suggestions or analysis are super appreciated.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 21, 2015, 09:28:49 am
content: That's normal.If you're very picky, you can add an R+C across the inductor (or output diode, or MOSFET) to dampen the ringing, but you will reduce efficiency as well.Instead of a clamp RCD snubber, a dV/dt snubber is often better: with proper values, it serves all three purposes (absorbing turn-off energy, reducing dissipation in the transistor; slowing the initial overshoot and dampening the subsequent shallow ringdown; and dampening the ringdown to +V).Schematic of a recent example; values are for a quite high current current level, hence the small resistors and large capacitors.Tim
Need help picking a solid state 'relay', condenser microphone circuit - Page 1
Forum section: electronics / projects

author: pilotplater
author_rank: Newbie
timestamp: September 07, 2016, 07:47:15 pm
content: I'm working on some audio stuff for headsets in a flight simulator, and I'm trying to work out some circuits to switch the microphones on and off on the headsets.The challenge with switching these mics is they're condenser mics, and as such require the 40-something volt phantom power. They make a good 'pop' when you connect and disconnect them. I've counteracted that successfully by switching a capacitor instead of the mic itself, so the phantom power is always getting to the mic but the ripples of the audio signal are smoothed out while the capacitor is connected low-pass filter style:This circuit works great with a normally closed switch for one part of the project. If you talk right into the mic some low frequencies will get through, but these are easily drowned out by the rest of the sounds coming from the simulator. I'd like to expand this circuit to add a "squelch" feature, where unless you talk on the headset, the audio gets attenuated (no background noise, this would emulate the real aircraft system). I can come up with a circuit using BJTs to detect the peaks and create a digital on/off signal, but I don't know enough about bidirectional transistors to replace the physical pushbutton right now. I could do it with clicky relays easy, but it seems wrong to abuse a relay with an on/off cycle every time you start/stop talking.The part needs to be able to switch very small ac voltages and currents, because we're dealing with only milivolts +/- on the mic side of the preamplifier. It's not really possible with my current setup to interrupt the signal between the preamp and mixing board because it's an all-in-one unit that I don't want to take apart.Any ideas would be great!

author: tatus1969
author_rank: Super Contributor
timestamp: September 08, 2016, 06:01:48 am
content: how much AC do you have? Presumably less than 0.5v in amplitude? You could switch that with a MOSFET. And even if it is more, the capacitor will adjust to the proper bias.
Need Help - Tactile button placement too inconsistent for molded housing  - Page 1
Forum section: electronics / projects

author: Jason.Mort
author_rank: Newbie
timestamp: February 27, 2023, 02:27:03 pm
content: We have a PCB with right angle tactile button; however, our vendors are unable to hold proper placement of the button. It's still usable but does cause it to be more difficult to use. The space constraints around the board negate the use of a through hole button. The board is mounted to an ABS mount/housing, with an over molded TPU button aligning with the tactile button on the board. Some assemblies are spot on, and others have the tactile button up to 1mm away from the TPU button, making it more difficult to use. Has anyone else in here experienced this before? Thinking of trying a drop of quick setting silicone between the two to take up any gap.

author: MarkS
author_rank: Unknown
timestamp: February 27, 2023, 03:19:03 pm
content: A through hole tactile button wouldn't take up any more space than a surface mount and the holes are VERY tiny. Are you sure this is an impossibility?

author: Jason.Mort
author_rank: Newbie
timestamp: February 27, 2023, 04:01:59 pm
content: The problem is the leg length sticking out past the PCB. There's less than 1/32" between the board and a mirror in the final assembly. If the vendor doesn't trim the legs after soldering, it would most likely scratch the paint on the back of the mirror.

author: CountChocula
author_rank: Unknown
timestamp: February 27, 2023, 07:01:21 pm
content: Is recasting the TPU button a possibility? You could change the profile so that it normally leaves the same gap but has more travel and can be pushed further down to account for the variance in the underlying tactile button's placement.

author: tooki
author_rank: Super Contributor
timestamp: February 27, 2023, 11:19:05 pm
content: Quote from: Jason.Mort on February 27, 2023, 04:01:59 pmSurely there exist some SMD buttons with a plastic locating peg (which will stick into, but not through, the PCB).If not: could you maybe reduce the size of some of the button’s SMD pads so that surface tension pulls it into position?

author: thm_w
author_rank: Super Contributor
timestamp: February 28, 2023, 01:52:44 am
content: Just to confirm, the ABS white plastic part at the top is located to the edge of the PCB? Or to some other hole on the PCB right? So the only variation here is the distance of the tactile switch from the edge of the PCB.Quote from: tooki on February 27, 2023, 11:19:05 pmYes many types exist. With plastic or metal locating pegs.