hybridfree/eevblog-posts huggingface dataset:
Please help me identify this IC - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: October 17, 2020, 07:13:21 pm
content: the IC is used in Lenovo Ideapad MIIX 310Here are picturesI marked the IC with a red arrowhttps://ibb.co/jDs9Wsband on this picture the IC is from the bottomhttps://ibb.co/Stcsjz2There is a three-line description on the ICMPGG2625B716Anyone have any idea what IC is that?Thanks

author: picburner
author_rank: Frequent Contributor
timestamp: October 17, 2020, 07:31:43 pm
content: It is a MP2625B, a single cell switching charger.Datasheet

author: amyk
author_rank: Super Contributor
timestamp: October 17, 2020, 07:34:28 pm
content: MP2625GL. Search for images of this IC to confirm the match.

author: picburner
author_rank: Frequent Contributor
timestamp: October 17, 2020, 08:36:27 pm
content: MP2625BGL if we want to be precise

author: Jane
author_rank: Frequent Contributor
timestamp: October 17, 2020, 09:09:32 pm
content: Thank you for help.But how did you find that?There is different marking on that IC?

author: picburner
author_rank: Frequent Contributor
timestamp: October 17, 2020, 09:41:54 pm
content: QuoteGoogle is your friend, just put the right keywords.QuoteFrom the datasheet I linked earlier:

author: amyk
author_rank: Super Contributor
timestamp: October 18, 2020, 09:30:13 pm
content: Google has become increasingly horrible for finding IC markings, that I usually use chip.tomsk.ru instead.
Please Help Me Identify this part: - Page 1
Forum section: electronics / beginners

author: jcw0752
author_rank: Contributor
timestamp: July 17, 2018, 04:07:54 am
content: While cleaning out the backroom of an Electronics Store we came across about 100 of these chips. I took them to the shop but I have not been able to determine what they are. Resistance readings are very high and capacitance readings are negligible. Hamlin is now owned by Littlefuse. The 8235 on each appears to be a date code which makes sense as all the other chips that were with this lot all came from the 1970s. Anyone have any ideas. I have tried to Google the image also with no results.

author: Jwillis
author_rank: Super Contributor
timestamp: July 17, 2018, 04:50:36 am
content: A resistor array?

author: TERRA Operative
author_rank: Super Contributor
timestamp: July 17, 2018, 05:27:37 am
content: Hmmm. Well the numbering doesn't like up with the pins, so that isn't showing pin numbers.Maybe it is a check list of the number of times it can do something, or that it has 12 configurations or the like.It almost looks to have a top cap of some sort, can you try to peel it of or open it up?It's almost like it's a little metal box or something. The legs are soldered in place.

author: ataradov
author_rank: Super Contributor
timestamp: July 17, 2018, 05:28:57 am
content: Quote from: TERRA Operative on July 17, 2018, 05:27:37 amIt is a ceramic package with green paint, it won't peel.It is most likely an array of some elements.

author: +Mikie
author_rank: Contributor
timestamp: July 17, 2018, 01:58:28 pm
content: If it isn't a resistor array (which should be easy to check with a meter), it could be a hybrid. Kinda like ASIC from last centuryIs this just curiosity or you planning to do something with it?

author: jcw0752
author_rank: Contributor
timestamp: July 18, 2018, 03:10:15 am
content: Hi Jwillis,Yes it turned out to be a special purpose resistor array. I will attach a picture of the inside after I removed some of the paint. The manufacturer had produced a low quality resistor array with 15 internal resistors of approximately 130 ohms each all tied to a common Pin 16. The User was likely using these arrays as DIP shunts by frying the unwanted resistor with a pulse of high current. This left all resistors damaged and at OL or at least quite high resistance except Pins 10 and 12. When used in a circuit with pull up resistors this damaged resistor array acted just like a 15 section programmable shunt. I wrote a more detailed report of the experiments that I ran thanks to suggestions from the folks that responded to my request for help. Here is a link to that report if I have done it correctly.https://www.element14.com/community/thread/64516/l/please-help-with-the-identification-of-this-partJohn

author: jcw0752
author_rank: Contributor
timestamp: July 18, 2018, 03:14:22 am
content: Hi +Mikie,A little bit of each. I can't do anything with it until I understand it. Now that I understand it I find I have about a hundred fairly useless arrays with 13 fused resistors each and only 2 non-fused resistors in each chip. Thanks for your question.John
Please help me identify this resistor - Page 1
Forum section: electronics / beginners

author: RogerMc
author_rank: Contributor
timestamp: February 12, 2014, 04:40:56 pm
content: Destroyed this component and need to replace it.It is a 100 ohm, 3 watt, 5% resistor.What I do not know is the manufacturer, and the reason there are no color bands.What is the replacement, please?Thanks!

author: Simon
author_rank: Unknown
timestamp: February 12, 2014, 04:42:11 pm
content: It does not matter who made it and there are no bands because it is big enough to write on

author: grumpydoc
author_rank: Super Contributor
timestamp: February 12, 2014, 04:43:56 pm
content: QuoteAnother 100 ohm 3W resistor?

author: RogerMc
author_rank: Contributor
timestamp: February 12, 2014, 04:44:42 pm
content: It does matter who made it. I want *this* specific part. *WHO* is the manufacturer please?

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 04:51:12 pm
content: Quote from: RogerMc on February 12, 2014, 04:44:42 pmIt might be Matsushita, now Panasonic.

author: RogerMc
author_rank: Contributor
timestamp: February 12, 2014, 04:53:07 pm
content: Quote from: retiredcaps on February 12, 2014, 04:51:12 pmBingo! Thank you sir!

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 04:53:50 pm
content: Example picture of logo.http://www.wellgainelectronics.com/matsushita3w180ohm5erg-3fjs181d.aspx

author: RogerMc
author_rank: Contributor
timestamp: February 12, 2014, 05:02:10 pm
content: Quote from: retiredcaps on February 12, 2014, 04:53:50 pmThat's it! Thank you sir!

author: ConKbot
author_rank: Super Contributor
timestamp: February 12, 2014, 05:42:25 pm
content: Quote from: RogerMc on February 12, 2014, 04:44:42 pmsmells like replacement parts medical/.mil/aero/some other 'qualified' electronics

author: grumpydoc
author_rank: Super Contributor
timestamp: February 12, 2014, 06:30:39 pm
content: QuoteThat wasn't clear from your original post, glad to see someone was able to identify it for you.

author: KJDS
author_rank: Super Contributor
timestamp: February 13, 2014, 09:59:48 am
content: Quote from: ConKbot on February 12, 2014, 05:42:25 pmIf that were the case, then you'd just ask the original equipment suppliers for a replacement or a manufacturer and part number.
Please help me identify this solder wire? - Page 1
Forum section: electronics / beginners

author: saflyfish
author_rank: Contributor
timestamp: September 03, 2025, 08:54:20 am
content: I cant seem to find the correct info on the Tin/Lead ratio for this product?

author: sleemanj
author_rank: Super Contributor
timestamp: September 03, 2025, 09:10:49 am
content: That company makes many different solders.The blue label appears to indicate that it is leaded solder, but there is no marking to show the ratio, or flux content.I expect the only way you can find out, is to ask them if they can tell from what looks to be a part or serial number (MO...).With that said, the label says 9#, and counting from the bottom on the table at the bottom of their solder pages the 9th entry is 60%, and given than 60/40 is the most common leaded solder (probably, maybe 63/37 these days, but one or the other), I'd hazard a guess that it is indeed 60/40.

author: saflyfish
author_rank: Contributor
timestamp: September 03, 2025, 09:14:00 am
content: Yea i have sent them multiple emails with no response.

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: September 05, 2025, 10:40:25 am
content: I think you can check this website and ask them.https://www.dglzd.com/
Please help me in identifying this component  - Page 1
Forum section: electronics / beginners

author: himanshu_hny
author_rank: Newbie
timestamp: March 03, 2018, 01:30:16 pm
content: I am getting difficulty in finding this component. it is marked with A1 V. This is used in Commander Sk VDF Model No. SKA1200025.Please Help.Thank You,Himanshu Sharma

author: Mechatrommer
author_rank: Super Contributor
timestamp: March 03, 2018, 01:40:37 pm
content: bjt in bce configuration...

author: himanshu_hny
author_rank: Newbie
timestamp: March 03, 2018, 01:44:36 pm
content: can you give exact replacement component

author: beenosam
author_rank: Regular Contributor
timestamp: March 03, 2018, 03:18:33 pm
content: Quote from: himanshu_hny on March 03, 2018, 01:44:36 pmIt's probably unlikely since it isn't detailed enough. I can't even find any information based on what you said.

author: amyk
author_rank: Super Contributor
timestamp: March 03, 2018, 05:05:50 pm
content: http://www.s-manuals.com/smd/a1

author: Momchilo
author_rank: Regular Contributor
timestamp: March 03, 2018, 05:12:50 pm
content: Should be this one:https://www.onsemi.com/pub/Collateral/BAW56LT1-D.PDFThe "V" is just a date code.

author: Jwillis
author_rank: Super Contributor
timestamp: March 04, 2018, 03:22:13 pm
content: I know some of you folks don't like PDF files.I have 1000's of them and haven't had a problem.But anyway this code book is really helpful in identifying SMD's.I use it a lot.I haven't been able to find a more current one but this should be still valid.You download it from herehttp://www.sphere.bc.ca/download/smd-codebook.pdf
PLEASE HELP ME TO FIND THIS CONNECTOR? - Page 1
Forum section: electronics / beginners

author: RaymondRosas
author_rank: Contributor
timestamp: November 29, 2024, 02:18:09 am
content: Hello, Sir. I would like to inquire about a connection I cannot find online. Could you please share a link where I can purchase it? Thank you.

author: amyk
author_rank: Super Contributor
timestamp: November 29, 2024, 02:41:16 am
content: https://www.smithsinterconnect.com/getattachment/9978aa65-8d54-40ed-a2a0-53d691eacee2/KA-Series-Catalogue-V1-4-USLetter.pdfMilitary/aerospace stuff? You're not going to like the price, and I suspect if you're not American they are unlikely to sell you any.

author: RaymondRosas
author_rank: Contributor
timestamp: November 29, 2024, 02:55:24 am
content: thank you so much sir.
Please help me understand this circuit. - Page 1
Forum section: electronics / beginners

author: braintree
author_rank: Newbie
timestamp: January 11, 2018, 03:28:13 am
content: Hi, first time callerI've just built this circuit and it sounds really cool. It's designed by the original drummer of Split Enz.It's got a weird spitting frying pan sound.As a naive guess I think it looks like the first op amp drives a signal into that diode ladder. Then something like, the higher the signal voltage the more of it passes thru the "gate" of more distant diodes. Like a kind of staggered set of sluice gates.As to how the signal is mixed together again on through that outgoing op amp, I'm confused.I'll run a signal into it and poke around with my oscilloscope.

author: braintree
author_rank: Newbie
timestamp: January 11, 2018, 03:29:51 am
content: this is how it sounds
Please help me understand this soft latching MOSFET switch - Page 1
Forum section: electronics / beginners

author: mianchen
author_rank: Regular Contributor
timestamp: January 05, 2014, 01:57:30 pm
content: #!Noob Alert!#I love this little circuit and have used it in a few of my projects. Minimal parts count and easy to make. I'm even thinking of designing a tiny board for it and had the PCB made so I can use it in my other project easily.Anyway, when I connected this to a headphone amp (TDA1308) I made for my wife, it won't turn off.I managed to make it work by connecting an LED between the OUT and GND of the switch circuit and increased the cap to 200nF. I don't want to use an LED in this case, and I don't quite understand why it has to be there to make it work. Please enlighten me.

author: cowana
author_rank: Frequent Contributor
timestamp: January 05, 2014, 02:13:37 pm
content: The LED is acting as a load for the circuit. You should be able to connect the circuit you want to use this for in its place - and you could always add an external load resistor to pull a bit more current if required.

author: mianchen
author_rank: Regular Contributor
timestamp: January 05, 2014, 03:40:18 pm
content: It worked after I remove the 100uF cap from the TDA1308 circuit...... no LED or load resistor needed

author: Jon86
author_rank: Frequent Contributor
timestamp: January 05, 2014, 03:52:07 pm
content: Quote from: mianchen on January 05, 2014, 03:40:18 pmYou shouldn't remove that cap, an amplifier needs decoupling. Did it not turn off at all, or did it turn off after a while?

author: mianchen
author_rank: Regular Contributor
timestamp: January 05, 2014, 04:50:05 pm
content: Quote from: Jon86 on January 05, 2014, 03:52:07 pmIt didnt turn off at all with the 100uF cap. When the 100uF is replaced with a 1uF cap it works. The amplifier is powered by battery - is 1uF enough of decoupling?

author: Dave
author_rank: Super Contributor
timestamp: January 05, 2014, 05:36:49 pm
content: The problem is that the decoupling capacitor has enough charge turn Q1 back on after you switch it off with S1.You could try putting a diode after your switching circuit, so the charge from the decoupling cap can't flow back. Might as well use a schottky, to reduce the voltage drop.

author: mianchen
author_rank: Regular Contributor
timestamp: January 05, 2014, 09:34:10 pm
content: Quote from: Dave on January 05, 2014, 05:36:49 pmThank you Dave.why didn't I think of that? I knew it's something to do with the cap but a diode never came across my mindsorted
Please help me understand this Step Down Circuit - Page 1
Forum section: electronics / beginners

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: February 25, 2016, 12:52:15 pm
content: Hi everyone,for my next Youtube video I took a chinese corn style LED bulb to bits and discovered an (at least for me) interesting circuit for the power supply.I actually cant really understand how it works and would really appreciate if someone could help me out here. Attached is the schematic I draw from the circuit.What I can see is, that the transistor I marked with "1" in the circuit (which is marked "Y" at the case as it is the tiny little SO-28 (?) thingy) should be the main "power" transistor switching the upper winding of the transformer. The other (TO-92) Transistor is marked 3020, but what does that one? On the other hand this looks like something like an darlington array...I guess the lower winding of the transformer is some sort of feedback winding to provide either a reference voltage or some kind of clock signal? Where does the switching transistor get its clock from anyways? And how is that thing regulated? Is it regulated at all? I am confused...Just for reference I attached a picture of the PCB, where I desoldered the transformer and the 4n7 cap.

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: February 26, 2016, 11:14:37 am
content: Thanks! That solved it completely!
please help me with pcb - Page 1
Forum section: electronics / beginners

author: justin66
author_rank: Regular Contributor
timestamp: February 24, 2015, 07:07:32 pm
content: i felt i know something about electronics but as i dive in i see i dont know anything im here with pretty easy thing i want to build an amplifyer here is the deali bought sodium persulfate to make copper go away... i think im gonna make that liquid fine but i was looking up know to design pcb and i stuckcan you please teach me how do i do pcbs nothing spectacular its only single sided board with low pass filter and simple ICi have tda2003 with all parts necessary but i also want to add a low pass filter on it so i was dumb enough to buy 2 lm741here is the picture of both lm741 and tda1554http://www.part.lt/img/f4182d27ee5aeeaf3e7d9dcb497b5f00249.jpgi have an other project with tda1554 but im gonna manage it self if someone is willing to help me on 2003i want to make nice board so i came here asking for help and i would really appreciate it

author: Wilksey
author_rank: Super Contributor
timestamp: February 24, 2015, 09:24:22 pm
content: Your first step is to download and learn a CAD program, a few popular / free ones exist.Diptrace (Pin Limit)Eagle (Size Limit)KiCAD (Completely Unlimited and open source)MultiSim Blue (Mousers' offering of NI MultiSim, pin limited)RS Design Spark (Completely free / unlimited as far as I know)There are probably others which i've missed, but some people have success with a varied number of packages, Eagle and KiCAD are natively supported cross platform, not sure about the others.

author: ccayser
author_rank: Contributor
timestamp: February 24, 2015, 10:17:13 pm
content: It might also be a good idea to start with something simpler. Audio amplifiers are nice, but sometimes they can be a bit of pain as a first project. With a more simplistic project it would be much easier to trace mistakes if you made any.

author: bookaboo
author_rank: Frequent Contributor
timestamp: February 24, 2015, 10:20:21 pm
content: Skip the etching process, its an obsolete skill given the cheapness of proto PCBs these days.It *might* work out a little cheaper but its time consuming, dirty and results can vary.

author: JohnnyBerg
author_rank: Frequent Contributor
timestamp: February 24, 2015, 10:20:44 pm
content: Follow mybehind the scenesthread. I doing a complete design from schematic to pcb there.

author: justin66
author_rank: Regular Contributor
timestamp: February 24, 2015, 10:23:21 pm
content: A BIG thanks to you guys i will take in mind that i have to look out any mistakes.
please help me with resistor identification question - Page 1
Forum section: electronics / beginners

author: krayvonk
author_rank: Regular Contributor
timestamp: July 13, 2019, 03:13:35 pm
content: I was wondering PLZ could someone post a pic of the resistor that is 4 times the resistance of this one ->

author: chemelec
author_rank: Contributor
timestamp: July 13, 2019, 03:23:13 pm
content: Color Pic is Not very clear.Looks like Brown, Black, Red (1,000 Ohms) with a gold ring, so a 5% Tolerance.4 Times would be a Yellow, Black, Red. (4,000 Ohms.)But 4000 is Not a Standard Value. 3,900 is close. (Orange, White, Red)

author: Audioguru
author_rank: Super Contributor
timestamp: July 13, 2019, 03:25:43 pm
content: Your dim fuzzy photo seems to show brown, black and red bars which is 1k (1000 ohms). The gold bar is for a tolerance of 5%. There is no such resistor value of 4k (4000 ohms) but 3.9k (3900 ohms) is very close.

author: Audioguru
author_rank: Super Contributor
timestamp: July 13, 2019, 03:28:43 pm
content: Hi Gary. We Canucks think alike.I was busy swearing at a caller on a phone call from India who was selling Duck Cleaning again and again and again.

author: krayvonk
author_rank: Regular Contributor
timestamp: July 13, 2019, 03:48:00 pm
content: Audioguru-> My name isnt Gary, but yes indian cleaning services are fricken annoying. But thanks all for the polite help! off I go back to work.

author: MagicSmoker
author_rank: Super Contributor
timestamp: July 13, 2019, 04:02:18 pm
content: You might find it useful to study/download a chart of the E12 (10% tolerance), E24 (5%), E96 (1%) and E192 (0.5%) number series, as these are used for standard part values with the tolerances indicated parenthetically.

author: ArthurDent
author_rank: Super Contributor
timestamp: July 13, 2019, 04:24:21 pm
content: Here is the simplest solution using what you have on hand.

author: bob91343
author_rank: Super Contributor
timestamp: July 13, 2019, 04:39:31 pm
content: Yes those are 1000 Ohm resistors, and 4000 Ohms isn't standard.Since these are 5% tolerance, a 3900 Ohm resistor should suffice for replacement.Still, it depends on what you are doing. If those resistors have been selected then you may want to select their replacement as well. If your 3900 Ohm substitute turns out to be a bit too low, then increase it by adding a small series resistance. However it seems you want to reduce the number of parts so you could get a batch of 3900 Ohm units and select from those.

author: SM3VLC
author_rank: Newbie
timestamp: July 13, 2019, 11:25:18 pm
content: Don't forget to take power dissipation into account.if those 1k are in parallel and you replace them with only one, you might need a resistor that can handle up to four times as much power.

author: bob91343
author_rank: Super Contributor
timestamp: July 14, 2019, 01:56:24 am
content: You would need 23 Volts or so across a 1000 Ohm resistor to dissipate one-half Watt.
Please help recognize connector type - Page 1
Forum section: electronics / beginners

author: haizaar
author_rank: Regular Contributor
timestamp: June 22, 2019, 04:29:50 pm
content: Good day,I got my hands on a doll house for my girl. It think it's about 7+ years old. It has a led lighting system that uses unusual (for me) connectors - they look old like something Sony cameras used in pre-USB era. The problem is that one of the connectors is broken. I want to buy a new one and re-solder it. Can anyone recognize the connector type according to the attached pictures?Thank you!

author: bob91343
author_rank: Super Contributor
timestamp: June 22, 2019, 04:52:35 pm
content: That looks like a common connector for cell phones. I might even have some units or cables with that on it. But they don't seem to use it any more.

author: haizaar
author_rank: Regular Contributor
timestamp: June 22, 2019, 05:05:12 pm
content: Do you know the connector type/name? Something I can search for and order on aliexpress?

author: mikerj
author_rank: Super Contributor
timestamp: June 22, 2019, 08:50:53 pm
content: Looks a little like the Sony 4 pin Mini-B connector.

author: haizaar
author_rank: Regular Contributor
timestamp: June 23, 2019, 01:14:59 am
content: Thank you! It was a good hint.Further googling led me here:https://connector.pinouts.ru/4_pin_mini-usb-mini-B/It looks exactly like what I have. Indeed quite challenging to find nowadays.If someone knows the place that can ship such connector to Australia (or a sacrificial cable), I'll appreciate a link.Thanks again!

author: haizaar
author_rank: Regular Contributor
timestamp: June 23, 2019, 12:16:59 pm
content: Found one here if anyone interested:https://www.mycablemart.com/store/cart.php?m=product_detail&p=5202Going to try my luck with it.

author: malagas_on_fire
author_rank: Frequent Contributor
timestamp: June 23, 2019, 12:20:53 pm
content: The connector seems familiar to some small webcams such as l'espion mini II for data transfer.
Please help to identify this LED - Page 1
Forum section: electronics / beginners

author: Andyf97
author_rank: Newbie
timestamp: October 12, 2015, 04:40:30 pm
content: Please help identify this LEDFrom what I know it is some form of white Superflux Piranha 5mm with a 7.6mm Body.I know that there are hundreds, maybe thousands of such LEDS but hope to find this one because I was given a handful to test and it is perfect for an application I am doing.Bad part of all this is the person who gave me the few does not know any part number.Notice the unusual B & J stamped characters on the tops of two legs..Other images here.http://postimg.org/gallery/105blttga/59e1ef98/

author: dacman
author_rank: Frequent Contributor
timestamp: October 12, 2015, 09:44:43 pm
content: Look up an OVA LED at Newark or Farnell.

author: Fat
author_rank: Regular Contributor
timestamp: October 12, 2015, 09:47:34 pm
content: Pricey little fellow, aren't they?Fat

author: JoeN
author_rank: Frequent Contributor
timestamp: October 13, 2015, 02:23:01 am
content: Decent number of eBay sellers selling these things NOS at reasonable prices. If it was just a personal project I would buy and use them.http://www.ebay.com/sch/i.html?_nkw=OVA+LED

author: dadler
author_rank: Unknown
timestamp: October 13, 2015, 04:28:07 am
content: I bought a bunch of these cheapies on aliexpress, look similar to your picture:http://www.aliexpress.com/item/100-pcs-LED-5MM-Piranha-Super-Flux-White-Leds-4-pin-Dome-diodes-Wide-Angle-Super/32257258751.html

author: JoeN
author_rank: Frequent Contributor
timestamp: October 16, 2015, 12:32:29 am
content: For fun I bought a few from the eBay seller I linked previously. They are really neat LEDs. Breadboard friendly.

author: Andyf97
author_rank: Newbie
timestamp: October 17, 2015, 09:12:32 pm
content: Hi all,Sorry I had not got any reply notifications, thank you all for looking.The OVA LEDS do indeed look similar and the multicomp product in the link bellow does appear to have some markings on its legs although the lens is different.http://cpc.farnell.com/1/1/92361-multicomp-ova-1061-led-suprflx-wide-ang-dome-wht.htmlIt looks like a good starting point to track these down so I will certainly order a few of these to compare.

author: dacman
author_rank: Frequent Contributor
timestamp: October 19, 2015, 01:55:46 am
content: About all the OVA LEDs at Farnell have a 7.6 mm base (which is an industry standard). (Just click on the data sheet to find out.) If the bulb size is stated to be (for example) 4.6 mm or 5 mm, that is the bulb (or dome) size.

author: Psi
author_rank: Super Contributor
timestamp: October 19, 2015, 05:50:33 am
content: I have bought LEDs in the same form factor from this webstore, and they were good quality.http://www.hebeiltd.com.cn/?p=led.auto.piranha
Please help with Lead-Acid Fast-Charge IC - Page 1
Forum section: electronics / beginners

author: gcardinal
author_rank: Unknown
timestamp: July 30, 2014, 09:28:32 pm
content: hi!I have a board with BQ2031 chip on it -datasheet.It is on a board from: HP 348879-005 4.0 V cached battery for HP serversI have replacement on order, but since I live in Norway it is a few days away. So Im looking for alternative solution - and it is extremely urgent.First I have de-soldered all the batteries and connected to a DC supply in order to simulate healthy batteries. It didnt work as the board still was saying it was in a "Fault condition". It wasnt even trying our batteries or drawing any current from the batteries.In datasheet it says following:"If the battery voltage is less than the low-voltage threshold, the bq2031 provides trickle-current charging until the voltage rises into the allowed range or an internal timer runs out and places the bq2031 in a Fault condition."I only need to this battery to work for 30-60 second - give away a "green" signal - in order for the server controller to boot. And I cant replace the batteries them self.My question is:If I swap BQ2031 for a brand new BQ2031 chip will it by default start as "green" and boot up even if batteries are low or will it right away without delay enter a "Fault state" again?..And is there any other way to "trick" this board into thinking it has new batteries?

author: rexxar
author_rank: Frequent Contributor
timestamp: July 31, 2014, 01:25:10 am
content: If you're sure the batteries are healthy, replacing the IC should fix the problem-- if that is the problem.I'd try charging the batteries manually, then hooking them back up. I wonder if the system isn't testing the batteries, and your DC supply couldn't handle the load.If any of the batteries failed short, they could well have fried some internal circuitry. This happened to an old UPS I had, it blew the ass end out of the MOSFETS.
Please help with weird motor encoder signal - Page 1
Forum section: electronics / beginners

author: ZAHN
author_rank: Newbie
timestamp: September 16, 2020, 01:48:07 am
content: Attached is is the signal that is comming out of the motor encoder. The first image is at slow speed showing square waves with what appears to be sine waves inside? However at full speed the signal gets garbled. Anyone know how to fix it? Any insight would be greatly appreciated!

author: Tom45
author_rank: Frequent Contributor
timestamp: September 16, 2020, 01:54:35 am
content: Those traces look like they might be composites due to triggering difficulties.Try setting the sweep rate to 20 or 50 usec/div and then use single sweep to capture just one trace and then stop.
Please, I need help designing my PCB board. - Page 1
Forum section: electronics / beginners

author: amin08
author_rank: Contributor
timestamp: October 30, 2017, 11:56:31 pm
content: Hi!Recently I've been designing my final project PCB, and as you may know, I'm not a professional electronics designer. I would like someone to help me review the board(schematic and design) before sending it to manufacture.It's the only step left before finishing the project

author: basinstreetdesign
author_rank: Frequent Contributor
timestamp: October 31, 2017, 12:12:40 am
content: Ok, so let's see it.

author: amin08
author_rank: Contributor
timestamp: October 31, 2017, 06:24:18 pm
content: Ok, so the first part of the circuit is the power supply, basically, it's a power source switching circuit that changes from USB to DC(If USB is plugged in and we plug DC jack, USB is cut off). There's also a switch that selects between 10.8V battery and DC jack.Please, any advice or help is appreciatedThank you

author: ataradov
author_rank: Super Contributor
timestamp: October 31, 2017, 06:25:56 pm
content: Can you actually make a readable picture?

author: TomS_
author_rank: Frequent Contributor
timestamp: October 31, 2017, 06:41:47 pm
content: Quote from: amin08 on October 31, 2017, 06:24:18 pmYou might be best uploading the EAGLE schematic file itself, and/or a PDF export (for those that dont use EAGLE), rather than images of different pieces of the circuit. People will be able to help more effectively if you do this.

author: TK
author_rank: Super Contributor
timestamp: October 31, 2017, 07:11:00 pm
content: The Arduino UNO R3 has a similar circuit to switch from USB to DC jack:
Please ident this JST connector - Page 1
Forum section: electronics / beginners

author: online1234
author_rank: Contributor
timestamp: April 02, 2020, 11:48:50 pm
content: Hi there,I'm struggling to identify this JST connect.it's 2.0mm pitch. The closest I can find is PH2.0, but there's no 'slot' on the male connector.Please help...

author: Monkeh
author_rank: Super Contributor
timestamp: April 03, 2020, 12:52:07 am
content: JST EH. 2.5mm pitch.

author: online1234
author_rank: Contributor
timestamp: April 03, 2020, 11:51:01 am
content: Thank you so much
please identify make of this inductor - Page 1
Forum section: electronics / beginners

author: krazy707
author_rank: Newbie
timestamp: July 08, 2020, 02:29:25 am
content: Hi, can somebody tell me who is the manufacturer of this 2r2 inductor on this pcb, looks like high quality component,

author: wraper
author_rank: Unknown
timestamp: July 08, 2020, 02:40:42 am
content: QuoteLOL, just some cheap generic inductor.

author: amyk
author_rank: Super Contributor
timestamp: July 09, 2020, 02:51:30 am
content: ...and any inductor of the right specs is going to work just fine anyway. Unlike electrolytics.

author: krazy707
author_rank: Newbie
timestamp: July 09, 2020, 06:32:58 am
content: thank you, funny, it's some cheap chinese, let's see if anyone really finds the maker.
Please identify this Hall-Sensor-Chip - Page 1
Forum section: electronics / beginners

author: HighVoltage
author_rank: Super Contributor
timestamp: October 13, 2014, 10:46:23 am
content: I am looking for a datasheet of the Hall-Sensor chip in these pictures.The numbers to don't come up in google.May be someone has used this sensor before and give a hint of who the manufacturer is?Thanks.

author: kolbep
author_rank: Frequent Contributor
timestamp: October 13, 2014, 08:32:11 pm
content: If that is a qr barcode silkscreened on the back of the device,then scanning it with a qr barcode app on your phone may reveal a manufacturer

author: Rudane
author_rank: Regular Contributor
timestamp: October 14, 2014, 12:52:11 am
content: Looks like a Chinese made one.http://item.taobao.com/item.htm?id=18546230854.You'll have to contact them for the datasheet. It will likely be in Chinese. I use Google translate to translate the datasheet. It's a pain.

author: HighVoltage
author_rank: Super Contributor
timestamp: October 14, 2014, 07:47:37 am
content: @kolbepThe barcode did not reveal any useful information@RudaneThanks so much for the link.I will see, if they have an English datasheet or if they even speak English by email.It is a good start, thanks again

author: HighVoltage
author_rank: Super Contributor
timestamp: October 15, 2014, 08:22:55 am
content: I found the original manufacturer.InfineonPart Number: TLE4983C-HT E6747Problem solved.Thanks for all your help and input.BTW, this is not a typical Hall Sensor, as I expected...It is aProgrammable True power on sensorFeatures:- TPO True Power On functionality- Increased BTPO range- Mono-cell chopped Hall system- TIM Twisted Independent Mounting- Dynamic self-calibrating algorithm- End-of-line programm able switching points- TC of back-bias magnet programmable- High sensitivity and high stability of the magnetic switching points- High resistance to mechanical stress- Digital output signal (voltage interface)- Short-circuit protection- Module style package with two 4.7/47 nF integrated capacitors- Package: PG-SSO-3-91 with nickel platingDatasheet enclosed
Please look at my I2C waveforms, why isn't writing working as it should? - Page 1
Forum section: electronics / beginners

author: king.oslo
author_rank: Frequent Contributor
timestamp: October 30, 2013, 11:12:30 pm
content: Hello there,I have an MCU which I want to communicate via I2C to ADT7420 (Datasheet). It is a 0.25°C accurate, 16-Bit Digital I2C Temperature Sensor.Datasheet says that by setting the address pointer register to 0x0B, I should be able to read back the chip ID, which default value: 0xCB.Instead it looks like I am not reading back the 0x0B register, but instead the 0x00 register (the MSB temperature register), because the value change as I heat the chip with hot air. It looks like somehow, the chip doesnt change the address pointer to 0x0B.I do the communication like this:First 7-bit I2C addres (0b1001000), 1 write bit, I receive ack from the slave. I then write 0x0B (0b00001011) to the slave after about 50uS delay. Then I delay for 1 ms before 7-bit I2C addres (0b1001000), 1 read bit, and I receive ack. The slave then returns incorrect data.Please can you look at my waveforms and try and help me figure out what is going on?Thank you for your time.Kind regards,Marius

author: free_electron
author_rank: Super Contributor
timestamp: October 31, 2013, 12:00:18 am
content: oh wow. your traces are all sloped ... your bits are going to roll downhill ! either that or you need to put a brick under your oscilloscope so the screen is at least horizontal...

author: David_AVD
author_rank: Super Contributor
timestamp: October 31, 2013, 12:04:29 am
content: Do you have pullup resistors on the I2C lines? If so, what value?

author: free_electron
author_rank: Super Contributor
timestamp: October 31, 2013, 12:11:16 am
content: you are sending a STOP between setting the register address and reading the data. The AD will fal into sleep mode and reset the pointer ... you need to send a repeat startyou do this <START><ADDRESS><W><ACK><REGISTER NUMBER><ACK><STOP>...<START><ADRESS><R><ACK><READ DATA><STOP>you should do this :<START><ADDRESS><W><ACK><REGISTER NUMBER><ACK><REPEAT START><ADRESS><R><ACK><READ DATA><STOP>

author: king.oslo
author_rank: Frequent Contributor
timestamp: October 31, 2013, 01:26:52 am
content: Quote from: free_electron on October 31, 2013, 12:11:16 amSolved my problem. Thank you.M
Please post a photo inside AIXUN T420D - Page 1
Forum section: electronics / beginners

author: IQfuturo
author_rank: Newbie
timestamp: August 25, 2022, 09:29:13 am
content: Please post a photo inside AIXUN T420D

author: CaptDon
author_rank: Super Contributor
timestamp: August 25, 2022, 02:54:52 pm
content: I.P. not available for theft.

author: tunk
author_rank: Super Contributor
timestamp: August 25, 2022, 03:14:17 pm
content: Why?And please don't double-post.

author: CaptDon
author_rank: Super Contributor
timestamp: August 26, 2022, 01:05:44 am
content: Just a picture of the inside? Strange, I would expect a post like "Can anyone identify the value of this burned R11 on my T420D?" and a picture of the inside or circuit board of the O.P.'s unit. Please post a photo inside EMD 1010 diesel. Sorry, we have had so much I.P. stolen through BBS's and chat groups. Kind of like when Suzuki copied the Evinrude/Johnson/OMC V4 engines right down to the flaws!!!

author: IQfuturo
author_rank: Newbie
timestamp: August 26, 2022, 07:47:40 am
content: I want to buy and choose between AIXUN T420D, JBC DDU, JBC DMU.

author: CaptDon
author_rank: Super Contributor
timestamp: August 26, 2022, 02:01:05 pm
content: I don't own any of those models although I used the JBC stuff at my workplace and I had no complaints of operation or quality. Others here will share their experiences good or bad also to help you choose. As for just a picture of the insides as basis for your choice of unit to purchase, that won't reveal other people's real world experience with any of the units.

author: IQfuturo
author_rank: Newbie
timestamp: August 26, 2022, 04:33:18 pm
content: I would be grateful to everyone for the help, I want to change Weller WD1
Please post a photo inside JBC DMU / DME-2A / DME-1A / DME-9A - Page 1
Forum section: electronics / beginners

author: IQfuturo
author_rank: Newbie
timestamp: August 25, 2022, 09:23:20 am
content: Please post a photo inside JBC DMU / DME-2A / DME-1A / DME-9A

author: CaptDon
author_rank: Super Contributor
timestamp: August 25, 2022, 02:55:33 pm
content: I.P. not available for theft.
Please recommend a buck/boost module to connect to a 90W laptop power supply - Page 1
Forum section: electronics / beginners

author: FBMinis
author_rank: Regular Contributor
timestamp: July 14, 2023, 12:44:45 pm
content: Something like this?https://www.aliexpress.com/item/1005003820144742.htmlIf possible, I'd rather get one of these modules and use a laptop brick to make a regulated power supply. Something to test my arduino/esp8266 projects, stuff with 12V motors, etc.There are so many options out there and they all seem to do the same but prices vary quite a bit.(not sure if this is the correct forum subsection)

author: liaifat85
author_rank: Regular Contributor
timestamp: July 16, 2023, 07:09:46 am
content: Could not access the link. Don't know why.

author: Shonky
author_rank: Frequent Contributor
timestamp: July 16, 2023, 07:16:34 am
content: Link works fine but best to include the non language specific link IMO otherwise AliExpress gets carried away changing the display language everywhere which is annoying....https://www.aliexpress.com/item/1005003820144742.htmlSomething like that will probably work, but like most things AliExpress, your mileage may vary. Read reviews. Look at the customer photos. Look for versions that have the highest number of orders. I can't recommend specific ones but I see that same basic design is sold by many sellers, so read the reviews.Supply could be noisy or oscillate or not handle transients very well.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: July 16, 2023, 09:39:53 pm
content: I had this.It works, sort of.There are two issues:1. 4A output current is very optimistic approach. Even at 2A load, making 5V from 19V (laptop supply), will make output diodes to go around 125C and above within couple of minutes. I'd say that 1A is an all-purpose current which you should aim to with this module. Of course, when input-output voltages are close enough, you can juice a higher current.2. When the load is non-linear (LED) and you have CC mode enabled, the output voltage will self-oscillate, starting around 10hz (depends on output current)Conclusion: Look elsewhere.Same applies to similarly featured, but with color screen, FNIRSI branded modules.
Please recommend a capactor for this purpose - Page 1
Forum section: electronics / beginners

author: alank2
author_rank: Super Contributor
timestamp: February 26, 2016, 05:34:10 pm
content: I am currently using an aluminum in a project as the main cap (330 uF), but it is not low profile enough even though I've already picked the shortest fattest one I could find using digikey's search. The project is a 5V project.Cost isn't a huge factor as I wont' be making many. What I'd like is:FlatLong term durabilityWhat are aluminum-polymer good for?It seems like tantalum's have a bad rep - or do people not use them right?What about paralleling large ceramic like a couple of 150uF? They aren't cheap, but they are flat...Other ideas?

author: michaeliv
author_rank: Frequent Contributor
timestamp: February 26, 2016, 06:26:10 pm
content: How low profile do you need?How about:- Lay a long thin electrolytic on it's side.- Parallel 3x1210 or even 8x0805.

author: Eric_the_EE
author_rank: Contributor
timestamp: March 01, 2016, 06:06:39 pm
content: Are surface mount components an option for this project?

author: alank2
author_rank: Super Contributor
timestamp: March 01, 2016, 06:12:23 pm
content: Quote from: Eric_the_EE on March 01, 2016, 06:06:39 pmIt is practically all surface mount...

author: bktemp
author_rank: Super Contributor
timestamp: March 01, 2016, 06:13:51 pm
content: Large ceramic capacitors have a large tolerance and and a huge voltage dependency. You probably have to buy ceramic capacitors with more than 1000uF to get 330uF at 5V.https://www.maximintegrated.com/en/app-notes/index.mvp/id/5527Depending on your circuit tantalum caps may be fine.

author: Audioguru
author_rank: Super Contributor
timestamp: March 01, 2016, 06:14:45 pm
content: You forgot to post the schematic for us to see why you need such a high capacitance. Maybe by using a higher resistor value or a high input resistance circuit the capacitance can be much less.

author: alank2
author_rank: Super Contributor
timestamp: March 01, 2016, 06:33:43 pm
content: This is sort of general main capacitor purpose.. Probably the biggest instantaneous draw is the display which can go from 0 to 125mA very quickly. I think I'm going to go with 3 or 4 100uF ceramic capacitors and see how that does.
Please recommend an ESR meter - DIY kitset if possible - Page 1
Forum section: electronics / beginners

author: nzo
author_rank: Regular Contributor
timestamp: November 09, 2011, 07:29:56 am
content: I definitely doesn't have to be an expensive oneThank you!

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: November 09, 2011, 07:52:22 am
content: Here you go my friend:http://lmgtfy.com/?q=esr+meter+kit

author: nzo
author_rank: Regular Contributor
timestamp: November 09, 2011, 08:00:15 am
content: Thank you smart-assI guess I was asking what YOU (the members here) recommend. Is that ok with you mate?

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: November 09, 2011, 08:29:19 am
content: Quote from: nzo on November 09, 2011, 08:00:15 amYou are welcomeI can reccomend one from GME instruments. I use it almost daily for few months now and it has paid itself many times allready. It is easy and intuitive to use, it can test in circuit, it has a nice LED scale with common capitances so you know is cap bad or good immeadately. Also it can test charged capacitors because it discharges the capacitor first, atleast its manufacturers claim but im not willling to test how good it works on larger capacitors, the design is easy on the battery and can use rechargable or wallwart (which you dont get, but its quite common voltage). However if you insist on a kit i cant suggest you anything since i dont have experience with it and you can not build something so compact with nice case and all except you are willing to spend more money than in ready made instrument.

author: Psi
author_rank: Super Contributor
timestamp: November 09, 2011, 10:06:48 am
content: i dunno what price range your after, and it's not a kit buthttp://www.peakelec.co.uk/acatalog/jz_esr60.htmlhttp://www.peakelec.co.uk/acatalog/jz_esr70.html

author: Unknown
author_rank: Unknown
timestamp: November 09, 2011, 11:54:00 am
content: Altronics kit. No idea how usable it is.http://www.altronics.com.au/index.asp?area=item&id=K2574

author: kripton2035
author_rank: Super Contributor
timestamp: November 09, 2011, 01:06:28 pm
content: here on my web site, on the esr repository page, lots of schematics, open source for most of themfrom the simplest to more complicated esr meters.http://kripton2035.free.fr/esr-repository.html

author: saturation
author_rank: Super Contributor
timestamp: November 09, 2011, 07:50:47 pm
content: You can make a DIY on the fly one using a scope and an FG:http://www.anatekcorp.com/ttg/tiptrick.htm#Scope%20ESRIf you don't troubleshoot often the makeshift one can do.http://fullnet.com/~tomg/esrscope.htm

author: nzo
author_rank: Regular Contributor
timestamp: November 09, 2011, 10:07:58 pm
content: Wow - thank you all! That will keep me busy. Really appreciate it.
Please recommend ESP32 cam module  - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: July 13, 2020, 05:19:59 pm
content: I found this ESP32 Camera modules at aliexpress, as shown in the picture it says one module has logo AI on it but the other one has different logo, i wanted to buy some modules i and though if i buy wrong module by mistake, can someone suggest if it matters? or if someone can suggest some module that for sure works good,these modules do not have mic on it, can someone advise if there are modules that supports mic or any other module which could be better, please im looking for cheap options so i can only buy from aliexpress or ebay
Please review my Class D Audio Amplifier Schematic - Page 1
Forum section: electronics / beginners

author: Fcolor04
author_rank: Contributor
timestamp: March 10, 2023, 07:33:02 pm
content: Hello, I've made this class D audio amplifier schematic, before I get to assembling the board I'd like to ask for your review, does it work at all? I have no idea myself please help!Input is going to be 12V although it'd be great to try it out with higher input voltage due to that 0 ohm resistor "switch" that can forward all the power to the mosfetsMosfet choice is purely random, I think they are gonna be fine but I have no ideaTriangle oscillator frequency calculated via Online simulation, probably not accurateI await your suggestions!First edit: I forgot to add input level scaling op amp and 6V power line, Rev 2 is current one