hybridfree/eevblog-posts huggingface dataset:
smd chip inductors - Page 1
Forum section: electronics / beginners

author: m3vuv
author_rank: Super Contributor
timestamp: January 25, 2020, 10:28:21 am
content: just a quick question,can chip inductors be connected in parallel like resistors/capacitors,ive a project for an rf preamp that needs 200nh i only have 100nh chip inductors,can i put 2 in paralell to make 200nh?,cheers in advance.

author: iMo
author_rank: Super Contributor
timestamp: January 25, 2020, 10:41:56 am
content: Quote from: m3vuv on January 25, 2020, 10:28:21 amWith 2x 100nH in series yes..

author: Siwastaja
author_rank: Super Contributor
timestamp: January 25, 2020, 01:38:26 pm
content: 2 x 100nH in parallel makes 50nH. You want them in series.

author: m3vuv
author_rank: Super Contributor
timestamp: January 25, 2020, 01:51:50 pm
content: Thanks for that,i imagine the same rules apply like resistors,as in series and paralell then?,73 m3vuv.

author: Wimberleytech
author_rank: Super Contributor
timestamp: January 25, 2020, 02:21:35 pm
content: Quote from: m3vuv on January 25, 2020, 01:51:50 pmYeshttps://en.wikipedia.org/wiki/Series_and_parallel_circuits
SMD component ST  BET  identify - Page 1
Forum section: electronics / beginners

author: pienari
author_rank: Regular Contributor
timestamp: October 20, 2024, 03:40:01 pm
content: I try to repair HIAB wireless controller charger unit.I found burnt fuse and shorted component near to power connector.Google didnt help and AI told it is zener diode but i think it is some kinda overvoltage protector?.

author: pienari
author_rank: Regular Contributor
timestamp: October 21, 2024, 03:14:22 pm
content: I donno why i cant find any information ab. That part.Other TVS datasheets i figured out it is STMicroelectonics BET DO-214ABSo i think i chance it to some TVS 32v?Charger unit operating voltage is 12 to 24v.What kind TVS is used in lorry trucks?
Smd diode identification - Page 1
Forum section: electronics / beginners

author: koba30
author_rank: Contributor
timestamp: June 17, 2017, 01:39:09 pm
content: Hi, can anybody help me to identify this code print on a diodeCC73Thanks in advanceSent from my SM-G920I using Tapatalk

author: bktemp
author_rank: Super Contributor
timestamp: June 17, 2017, 01:52:44 pm
content: Maybe MMSZ5245ET1G:https://www.onsemi.com/pub/Collateral/MMSZ5221ET1-D.PDFBut the marking style looks different to other ON parts.

author: koba30
author_rank: Contributor
timestamp: June 17, 2017, 02:58:55 pm
content: Yes it isThanks for your help bktempSent from my SM-G920I using Tapatalk
SMD diode - Page 1
Forum section: electronics / beginners

author: avc4eva
author_rank: Contributor
timestamp: October 28, 2014, 10:40:32 am
content: Hi, I'm designing a PCB and am in need of a small package diode for protection from a small vibration motor.Originally on breadboard i was using a 1N4001 so am now confused on what diode to use for smd, my project is constrained to space.The Schematic designed is below and at the moment I'm using an SMA package diode but its rather large.In short i am wondering what process i would need to determine an smd equivalent diode for this PCB and for future reference.Thanks!

author: tggzzz
author_rank: Super Contributor
timestamp: October 28, 2014, 11:11:31 am
content: What are you protecting against?What type of motor?If it is reverse EMF/current from the motor, the diode should be across the motor. Assuming protecting from reverse EMF/current from the motor....In general the calculation will be something along the lines of:when transistor switched off, the same current will continue to flow through the inductor and diode; hence the diode must be able to take that forward currentenergy stored in the inductor will have to be dissipated somewhere; that will be in the diode with a 0.6V drop, so you can work out how long the current will flowif you want faster dissipation then add a resistor in series with the diode, thus "increasing the 0.6V" to V=0.6+IR; choose R so that V does not damage the other componentsYou would be well advised to find application notes for drivers for the type of motor you are using

author: avc4eva
author_rank: Contributor
timestamp: October 28, 2014, 11:13:59 am
content: Quote from: tggzzz on October 28, 2014, 11:11:31 amThanks for the reply, just realized schematic is wrong anode should not be on the base but across motor, thanks for prompting me. And ye it's against reverse current. I will do what you said thanks!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 28, 2014, 11:50:34 pm
content: 2N2222 won't draw any current that a common 1N4148 won't handle.1N4148W, MMSD4148, etc. are common numbers.Tim
SMD electrolytic cap identification. I can't figure out. Pics attached - Page 1
Forum section: electronics / beginners

author: N4v4jo
author_rank: Newbie
timestamp: February 25, 2024, 01:34:22 am
content: Hi, I have tried to find out the value of these two caps but after lot of research I kindly as for help in this forum. See picture attachedThe small one read6210050Fand the larger oneQ447 OEUDThese are in a IPOD Dock station/Speaker amplifier.Thank you in advance.

author: wraper
author_rank: Unknown
timestamp: February 25, 2024, 01:59:01 am
content: First one is 100uF 50V, made by Rubycon. Second 470uF 25V, Nichicon UUD series (low esr).https://www.nichicon.co.jp/english/series_items/catalog_pdf/e-uud.pdf

author: N4v4jo
author_rank: Newbie
timestamp: February 25, 2024, 04:47:33 am
content: Thank you very much!!!.
SMD Electrolytic capacitor markings - Page 1
Forum section: electronics / beginners

author: will_raymo2000
author_rank: Newbie
timestamp: January 12, 2017, 03:48:56 pm
content: Trying to repair a faulty USB soundcard and I suspect a couple of filtering capacitors have given up the ghost. They are surface mount electrolytics with the following markings:1006SE74I'm guessing 100uF but not 100% sure.Any help appreciated thanks!

author: Cupcakus
author_rank: Contributor
timestamp: January 13, 2017, 08:45:05 am
content: Every manufacturer uses different markings so it's hard to know for sure, but with those marks it should be 100uF 6.3V

author: German_EE
author_rank: Super Contributor
timestamp: January 15, 2017, 10:34:27 am
content: One other thing to note (one of those fabled traps for young players).A through-hole electrolytic capacitor has the 'band' next to the negative leadAn SMD wet electrolytic in a round can also has the black mark next to the negative leadAn SMD tantalum electrolytic in a plastic case has the mark next to the POSITIVE lead.

author: Howardlong
author_rank: Super Contributor
timestamp: January 15, 2017, 01:46:56 pm
content: Quote from: German_EE on January 15, 2017, 10:34:27 amI wonder (a) what they were thinking and (b) how many of us found that out the hard way?

author: German_EE
author_rank: Super Contributor
timestamp: January 15, 2017, 07:33:11 pm
content: (b) how many of us found that out the hard way?Count me among their number which is why I passed the information on, learn from my mistakes.

author: will_raymo2000
author_rank: Newbie
timestamp: January 15, 2017, 09:24:03 pm
content: Just to follow up on this... I replaced it with a 100uf radial capacitor with the leads bent to fit the pads and it didn't work. Replaced that with a 10uf and voila, it worked perfectly.Still got a very high frequency (audible) whine from something in the power section but it is markedly lower having replaced a couple of these capacitors.
SMD equivalent - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: September 09, 2016, 07:26:27 pm
content: What methods do you use to find an equivalent of a SMD part?It is rather difficult to find it ( at least for me) because SMD parts do not have model number written.

author: ElektroQuark
author_rank: Unknown
timestamp: September 09, 2016, 07:39:47 pm
content: They have mostly.

author: Dave
author_rank: Super Contributor
timestamp: September 09, 2016, 07:41:00 pm
content: The limited amount of space on small SMD packages has forced manufacturers to use the so-called SMD code. You can look up those codes on many websites (just google "SMD code search"). Here's oneexample.
SMD flat silent buttons - Page 1
Forum section: electronics / beginners

author: Yaroooo
author_rank: Regular Contributor
timestamp: February 09, 2020, 11:41:08 am
content: Hi all,I'd like to find a small silent tactile switch to substitute my loud "Click" switches. These are common momentary SMD switch found on every board.Here's an example image:Dimensions are 6x6.5x2 mm.Looking on internet I can't find silent switches of this dimensions, especially height.I found a lot Keyboard switches and the smaller one is this, used inside silent mouse (6x6x6.5)Did I use wrong terms when searching or is it impossible to have 2mm height button with silent attribute due construction?

author: jbeng
author_rank: Regular Contributor
timestamp: February 11, 2020, 01:42:36 am
content: Here's a link for a datasheet from C&K which might give you some ideas. I'm not sure if they have something in the height you require, but the KSC2 series are quiet. Not 100% silent, but the actuator button is rubber, so they are quiet.https://dznh3ojzb2azq.cloudfront.net/products/Tactile/KSC2/documents/datasheet.pdf

author: tooki
author_rank: Super Contributor
timestamp: February 11, 2020, 02:44:04 am
content: I think that for something like that, “silent” and “tactile” are very hard to unite, since the tactility comes from a collapsing metal dome, which will cause some click to resonate through the PCB. Some will be much quieter, but not silent like a linear keyboard switch.What about those metal domes that you solder right to the PCB?Or an actual rubber membrane keypad?
SMD Germanium diodes? - Page 1
Forum section: electronics / beginners

author: awallin
author_rank: Frequent Contributor
timestamp: November 10, 2015, 05:32:04 am
content: Hi,These RF-detection/AM-demodulation circuits use Germanium diodes (because of their low forward voltage drop I guess)http://electronics.stackexchange.com/questions/78530/how-can-i-tell-if-an-rf-transmitter-is-transmitting1N2701N34AAll google finds me is through-hole Ge diodes? Does anyone make SMD Ge diodes?Thanks!

author: Vgkid
author_rank: Super Contributor
timestamp: November 10, 2015, 05:39:23 am
content: Germanium diodes were obsolete for a long time, schottkey diodes offer a low voltage drop, and are in smd package, and also in T0- cased high power varients as well.

author: Teledog
author_rank: Regular Contributor
timestamp: November 10, 2015, 08:44:33 am
content: Does Germanium leak as much current as the Schottky?Just askin'

author: coppice
author_rank: Super Contributor
timestamp: November 10, 2015, 08:50:35 am
content: Quote from: Teledog on November 10, 2015, 08:44:33 amI don't know any Schottky diodes which are as low as 0.2V forward biased that leak as little as a germanium diode at room temperature. I'm not sure about when they are warmed up. However, your wallet will leak a lot less buying the Schottky diode.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 10, 2015, 01:16:13 pm
content: I think they're pretty close, as far as Vf and Ir. But the schottky will work to higher temperatures, and has no recovery time.Back diodes are also available, which have even less Vf (which is actually Vr, because they're actually a marginal kind of tunnel diode), and are usable for very small signals.Tim

author: free_electron
author_rank: Super Contributor
timestamp: November 10, 2015, 01:37:48 pm
content: Simp,y apply a dc bias.
SMD IC datasheet - Page 1
Forum section: electronics / beginners

author: RedX159
author_rank: Newbie
timestamp: September 18, 2025, 10:08:49 am
content: Hi everyone,I’m repairing a power supply board.On the primary side, close to the main MOSFET and HV input, there is a small 6-pin SMD IC.The top marking is simply **“7013”** (no manufacturer logo).I could not find any reliable datasheet for this chip.It seems to act as the PWM controller or MOSFET driver for the main transformer.Any datasheet, cross reference, or even a guess based on similar designs would be very helpful.Thanks in advance!

author: Ammar
author_rank: Regular Contributor
timestamp: September 18, 2025, 01:33:08 pm
content: More pics? Whole board, where it fits in, more context would be helpful.Can you replace the entire board?

author: wraper
author_rank: Unknown
timestamp: September 18, 2025, 01:40:31 pm
content: ^Yep, the context of its usage makes it an order of magnitude easier to find.

author: fzabkar
author_rank: Super Contributor
timestamp: September 18, 2025, 04:28:54 pm
content: Try this resource:https://vip-cxema.org/index.php/online-raschjoty/393-podbor-shim-kontrollera-po-vyvodam

author: RedX159
author_rank: Newbie
timestamp: September 18, 2025, 07:49:54 pm
content: Thanks for the reply.Here is the context:It is located on the **high voltage side**, very close to the **main MOSFET**,and directly in the **primary section of the main transformer**.From the position and surrounding parts, it looks like this IC is the PWM controlleror driver that handles the MOSFET switching on the primary side.

author: RedX159
author_rank: Newbie
timestamp: September 18, 2025, 08:15:52 pm
content: This resource is really great, but unfortunately I couldn’t find the IC in it. Thanks.
SMD IC datasheet - Page 1
Forum section: electronics / beginners

author: RedX159
author_rank: Newbie
timestamp: July 01, 2025, 10:59:05 am
content: Hi everyone,I've searched the SMD code, but couldn’t find a matching part number.Thanks in advance.

author: squadchannel
author_rank: Frequent Contributor
timestamp: July 01, 2025, 11:42:33 am
content: STMicroelectronics L6926

author: RedX159
author_rank: Newbie
timestamp: July 01, 2025, 01:01:39 pm
content: Thank you for your help! I really appreciate it
SMD IC Help - Page 1
Forum section: electronics / beginners

author: FearTec
author_rank: Regular Contributor
timestamp: November 06, 2020, 09:42:47 am
content: HelpI was applying Kapton tape to an MP3 ESP32 Feather (https://core-electronics.com.au/music-maker-featherwing-w-amp-mp3-ogg-wav-midi-synth-player-stereo-3w-amplifier.html) as I was going to add a heatsink and thermal epoxy as the chip gets way hot.Long story short I knocked off Pin 37 (Analog ground, low-noise reference) with side cutters while trimming off Kapton TapeLooking at the IC Manual I am trying to source a VLSI Solutions VS1053b to attempt[t to repair the board.Datasheet:https://cdn.sparkfun.com/datasheets/Dev/Arduino/Shields/VS1053B.pdfQ1) Where is the best place to order a legit chip with a recent version (v1938?)?I have heat gun and am keep to attempt a repair.

author: perieanuo
author_rank: Frequent Contributor
timestamp: November 06, 2020, 09:57:51 am
content: hi, with a good soldering iron (AND steady handa), that thing is not so complicated to restorejust don't rush or call a friend who can do it

author: FearTec
author_rank: Regular Contributor
timestamp: November 06, 2020, 10:18:29 am
content: Id rather replace the whole IC as there is no meat on the IC where the pin was.I'm trying to source a new IC and will use my new heat gun and solder paste and or wick and soldering iron to remove and replace.

author: amyk
author_rank: Super Contributor
timestamp: November 06, 2020, 02:36:59 pm
content: Grind away the package to expose more if you don't have enough leadframe to solder on, although even in its current state I can see metal, so solder will stick. This is not a difficult repair.

author: Ian.M
author_rank: Super Contributor
timestamp: November 06, 2020, 03:27:35 pm
content: It looks like pin 39 is badly bent towards the corner and may be touching 38. It may also be broken. If its not broken you'll need to pry it back enough to slip a sliver of kapton tape between the two pins.As Amyk has pointed out, dremelling away a bit of the package on that end of that side will expose plenty of leadframe to solder patchwires to.

author: Jwillis
author_rank: Super Contributor
timestamp: November 07, 2020, 08:21:56 am
content: It looks like you can get just the chip from Mouser .https://www.mouser.com/ProductDetail/Adafruit/1681?qs=GURawfaeGuDweTrI03sq1w%3D%3D

author: JustMeHere
author_rank: Frequent Contributor
timestamp: November 07, 2020, 09:41:54 pm
content: I'd push the pin back into place. Get a big tip with a little solder on it. Flux the pins. Drag across the pins. And should be done.

author: ebclr
author_rank: Super Contributor
timestamp: November 08, 2020, 12:53:30 am
content: https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20201107165240&SearchText=VS1053b

author: wraper
author_rank: Unknown
timestamp: November 08, 2020, 01:22:03 am
content: You can get it from Adafruit, Mouser and Digikey for the same price of $12.50 . Or buy from China you want cheaper.
SMD ic - Page 1
Forum section: electronics / beginners

author: mikeavelli
author_rank: Newbie
timestamp: June 03, 2015, 01:05:10 am
content: is it possible to test a 25 pin micro smd. if so how?

author: Mr.B
author_rank: Unknown
timestamp: June 03, 2015, 01:10:51 am
content: Yes - Using special type of 'socket'.Example:http://electronics.stackexchange.com/questions/98970/how-to-program-atmel-attiny88-not-45-or-85
SMD LED desoldering on heatsink plate? - Page 1
Forum section: electronics / beginners

author: Jan Catrysse
author_rank: Contributor
timestamp: June 04, 2020, 05:46:26 am
content: Hi,I am trying to nicely desolder some SMD LED's and replace them, on an aluminium heatsink PCB. Like those commonly found in garden or work lamps.But my preheater doesn't seem to heat enough, so I have to raise my hotair temperature way to high and I'm burning my LED's.Does anyone has a good advice on how to do this the right way?Does anyone has an advice on a good heating plate for this? I found a Weller WHP 1000 Preheating plate, but it only goes upto 300 degrees Celsius, and I don't know if that's enough?Thank you

author: JustMeHere
author_rank: Frequent Contributor
timestamp: June 04, 2020, 08:34:20 am
content: 300 C is enough.

author: GoneTomorrow
author_rank: Regular Contributor
timestamp: June 04, 2020, 09:00:06 am
content: In the flashlight modding world most people just go medieval on its ass and use something like an electric frypan to heat the MCPCB to swap LED's, since most people can't justify a proper board heater just for this.

author: Jan Catrysse
author_rank: Contributor
timestamp: June 04, 2020, 09:15:23 am
content: Thank you!

author: Siwastaja
author_rank: Super Contributor
timestamp: June 04, 2020, 11:34:53 am
content: My suggestion is to preheat slightly below the melting point of the solder, maybe 150 degC for leaded and maybe 200 degC for lead-free. Then you supply the "last bit" of heat with the hot air gun or soldering iron.Note that practically all components survive those "just below melting point" temperatures forhoursjust fine, so you are not in a hurry - preheat slowly, take your time, so the whole piece heats up evenly with no colder areas.

author: Jan Catrysse
author_rank: Contributor
timestamp: June 04, 2020, 11:56:51 am
content: Thank you, so if I have a device that would have a max temperature of 300 I would be largely ok.I will try that.

author: Jan Catrysse
author_rank: Contributor
timestamp: June 05, 2020, 05:38:38 am
content: Uyue 946c is the machine I found on Ali Express. I will give it a try.

author: MosherIV
author_rank: Super Contributor
timestamp: June 05, 2020, 07:24:09 am
content: If you do not have electric pan try clothes iron, it even has temperature control but it is not precises.Should be good enough to preheat the heat sink
SMD led orientation check with multimeter? - Page 1
Forum section: electronics / beginners

author: RL_Tracksuit_Electro
author_rank: Contributor
timestamp: January 01, 2020, 10:10:33 pm
content: Fast forward, using the markings on the smd led I was able to determine the cathode & anadode and everything worked.However, when I try to use my multimeter (a cheap Tacklife) diode test setting to double-check cathod/anode, the screen never changes nor does the led light up. I tested other diodes (not leds) with that setting and it works.I have no idea exactly what kind of leds they are. Is it "normal" that some leds can't be tested by some multimeters? I don't have any other smd leds handy, nor another multimeter.

author: fcb
author_rank: Super Contributor
timestamp: January 01, 2020, 10:14:48 pm
content: White & Blue LED's have a higher forward voltage, so your DMM might not be able to push them into conduction - so they might appear open-circuit.

author: RL_Tracksuit_Electro
author_rank: Contributor
timestamp: January 02, 2020, 01:44:41 am
content: Indeed they are blue, thanks!

author: fcb
author_rank: Super Contributor
timestamp: January 02, 2020, 01:23:18 pm
content: One trick I've used is to put a 1.5V cell in series with the multimeter in "diode check" mode (red lead to batt-, batt+ to DUT). This is enough usually to light the most stubborn blue/white LED's.
SMD Marking BGA Analog Devices - Page 1
Forum section: electronics / beginners

author: testian
author_rank: Regular Contributor
timestamp: June 22, 2017, 11:00:29 am
content: I am struggling identifying the following SMD part:Manufacturer: Analog DevicesSMD Marking:BGACase: MSOP8 (probably)It should be an AD8671 but I am not sure, because the datasheet does not mention this code. Also searching for BGA in goggle is not very helpful. Does anyone have some resources where to look?

author: bktemp
author_rank: Super Contributor
timestamp: June 22, 2017, 11:18:03 am
content: It looks like they removed that package from the datasheet.http://www.bdtic.com/DataSheet/ADI/AD8671_AD8672_AD8674.pdfOn page 16:AD8671ARM-RBranding: BGA
SMD Marking help - Page 1
Forum section: electronics / beginners

author: Tenrao
author_rank: Newbie
timestamp: November 30, 2023, 12:32:20 pm
content: Hello together,I have a SMD component which I try to identify. I checked several websites with smd lookup tables but nothing seems to fit.On the SMD component is written "CVV". The component is a SOT-363 (or SOT-23-6) component. Pin 2 and 5 are shorted together, Pin 3 is +5V and Pin 6 is -5V.Pin 2 and 5 are connected via voltage divider to an opamp output.My guess is that the component is used for output saturation protection or impedance control (maybe both). Application of the whole circuit is audio amplifier.Maybe the wanted component is another opamp or transistor array. Maybe from Fairchild/On Semiconductor.Maybe someone has an idea.Thank you very much!

author: m k
author_rank: Super Contributor
timestamp: December 05, 2023, 05:35:14 pm
content: An end point, dual diodes, how are pins 1 and 4?

author: liaifat85
author_rank: Regular Contributor
timestamp: December 07, 2023, 03:51:12 pm
content: It can be a custom component too.

author: Tenrao
author_rank: Newbie
timestamp: December 13, 2023, 01:30:52 pm
content: Yeah maybe it is a custom component...here is a more detailed schematic. Maybe they use the component to get a constant input impedance and this is sort of double transistor for "bootstrapping" or maybe another opamp or whatever.I have never seen something like this before

author: m k
author_rank: Super Contributor
timestamp: December 13, 2023, 07:44:11 pm
content: Are those lower diode things correct?So estimating that there is more to be damped.Or since it was damped there it must also be damped here.
SMD Micro USB Type B port solder-pad footprint to header - Page 1
Forum section: electronics / beginners

author: ahfdjpi
author_rank: Newbie
timestamp: August 22, 2018, 10:33:47 pm
content: Goal: I want to hard-wire a USB 2.0 cable to an SMD USB 2.0 type B port solder pad in a way that is mechanically robust (similar in mechanical characteristics to a AWG 28 conductor soldered through-hole). I want to do this by using a adapter component that uses the same SMD footprint as a micro USB 2.0 type B port, but that provides header pins (or larger, more robust solder pads or a through-hole platform) to connect to INSTEAD OF a standard type B micro USB port (kind of like a soldered-on breakout board, but just for the micro USB type B port). This adapter would provide more mechanical strength between the SMD solder pads and the cable conductors.Does such an adapter component exist? Are there other, better workarounds?

author: westfw
author_rank: Super Contributor
timestamp: August 22, 2018, 10:59:53 pm
content: QuoteThere are micro USB-B connectors available with long-ish through-hole tabs that should be much more physically robust that the more common all-SMT-pad versions.
SMD microphone testing  - Page 1
Forum section: electronics / beginners

author: Jane
author_rank: Frequent Contributor
timestamp: January 26, 2017, 06:18:34 am
content: From time to time I must repair a mainboard where a SMD microphone is faulty, so I desolder the old and solder the new one.Is there any way how to test that SMD microphone before soldering?(It may happen that SMD microphone is faulty and a supllierdoes not replace the SMD microphone that had been soldered)

author: jeroen79
author_rank: Frequent Contributor
timestamp: January 26, 2017, 09:13:14 am
content: You'll need some other way to make contact like little grabbers or by pressing it against some exposed pcb pads.Or make some pointy bendy springy electrodes that you press the part against.

author: RoGeorge
author_rank: Super Contributor
timestamp: January 26, 2017, 09:55:24 am
content: If the microphone is electret type, please look into its datasheet for any special requirements of the soldering temperature curve.Electret mics are usually very sensitive to temperature, so if they are heated too long or at a temperature to big while soldering, then the mic can loose a lot of its sensitivity or even become unresponsive. The damage during solder is not reversible, the main cause being depolarizing or even melting the electret inside.

author: Jane
author_rank: Frequent Contributor
timestamp: January 27, 2017, 05:28:27 pm
content: So, no possibble testing ?

author: jeroen79
author_rank: Frequent Contributor
timestamp: January 27, 2017, 05:46:20 pm
content: Quote from: Jane on January 27, 2017, 05:28:27 pmQuote from: jeroen79 on January 26, 2017, 09:13:14 am

author: Jane
author_rank: Frequent Contributor
timestamp: January 27, 2017, 08:52:07 pm
content: One thing is having good contacts but the other way is what I should measure on the output.What voltage should I measure on the output. Must I use an oscilloscope or just DMM? Must I use an amplifier?

author: RoGeorge
author_rank: Super Contributor
timestamp: January 27, 2017, 09:36:39 pm
content: Quote from: Jane on January 27, 2017, 08:52:07 pm- That is what you should have asked in the first place.- Second, be specific. Tell what kind of microphone are you talking about, and what is the problem. If you don't know the exact model of the microphone, then at least put a picture of it, or tell where from is that mic.If it's what I think it is ,but my mind reading ability are not so good sometimes, then a DMM on diode measuring setting might be enough. Be careful, microphones have a + and a -. Don't power them in reverse.
SMD NPO Capacitor Visuals - Page 1
Forum section: electronics / beginners

author: metrologist
author_rank: Super Contributor
timestamp: October 30, 2018, 07:25:31 pm
content: I have a lot of scrap boards that I want to salvage a good low tempco 1nf capacitor. What do they look like and how can I measure the tempco? I have a DE5000 tester for the measurement. The caps are generally a light tan, brown, creame, orange, purplish, gray, and black. Some are taller than wide and some are wider than tall, and some are square aspects or cubes.I tried a brownish 1nF cap using an avr component tester and placing a hot object on the cap then a frozen one (both non-conductive) and I saw 1007 to 1025pF. Is it that simple, 18ppm ~100C?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 30, 2018, 08:20:22 pm
content: C0G (or in the old scheme, NP0; but not NPO as frequently typoed!) is usually a lighter color, yes, with type 2 (usually X5R and similar) being tan or brown. (Black is probably a ferrite bead or inductor. Bright colors may be tantalum or niobium polarized capacitors?)C0G are rare to find over 1nF or so, or even 220-470pF in the smallest sizes (0402 and below). That's where the cost advantage of type 2 dielectrics take over.Yes, a stable value over temperature is a strong indicator that it's C0G. The value will also be stable over voltage, which can be tested by measuring the rise time of a square wave into an RC filter, varying the average level (DC bias) of the square wave to see if the rise time changes. (That's, uh, a little hard to do without a signal generator and oscilloscope, but you can just as well measure it directly, by connecting two capacitors in series, biasing the middle node with a large value (many Megs?) resistor, and varying the bias voltage with respect to ground. Your AVR tester will measure it just fine this way.)Tim

author: wraper
author_rank: Unknown
timestamp: October 30, 2018, 08:29:10 pm
content: C0G usually have light color like white, light grey, slightly pink. Brown caps are basically guaranteed to be type II/III ceramic.

author: metrologist
author_rank: Super Contributor
timestamp: October 30, 2018, 11:30:59 pm
content: ewe Folks are awesome! Google is not helping me too much lately, especially if you can't get the correct term!I actually did notice it eventually and results were better, but still covered everything under the sun... I also thought of concentrating on the circuit in which they are placed, as they are often RF related, such as decoupling caps probably are not of much interest here...
SMD part identification - Page 1
Forum section: electronics / beginners

author: jkprg
author_rank: Contributor
timestamp: November 26, 2020, 08:04:12 am
content: Hi,can you help me to identify the SMD part from the attached picture?It's usually near (or part of) power circuitry. Like ferrite bead couple but why would it be asymetrical..Thanks a lot

author: ataradov
author_rank: Super Contributor
timestamp: November 26, 2020, 08:36:28 am
content: It is a current sense shunt resistor. It is asymmetrical so that four-terminal measurement is possible.Here is a description of the ideahttps://www.digikey.nl/en/articles/fundamentals-of-current-measurement-part-1-current-sense-resistors
SMD part identification - Page 1
Forum section: electronics / beginners

author: Kratto
author_rank: Newbie
timestamp: March 09, 2021, 05:09:56 pm
content: Hi. Can someone help me to identify these two similar SMD components? My guess it could be burned SMD fuses, 0805 package. But I'm not a hundred percent sure.

author: ataradov
author_rank: Super Contributor
timestamp: March 09, 2021, 06:47:02 pm
content: This package usually means fuse, but there is no way to identify the actual part number or parameters.
SMD part identification ST MT C722 - Page 1
Forum section: electronics / beginners

author: Kratto
author_rank: Newbie
timestamp: December 09, 2017, 01:08:53 am
content: Hello, I can't identify diode, maybe someone can help me pls? it is bad as it seems, no resistance, no voltage drop. The code is ST MT C722, can't find on the internet.
SMD plastic/metal "things" just to add some thickness to PCB ? - Page 1
Forum section: electronics / beginners

author: ratatax
author_rank: Regular Contributor
timestamp: June 20, 2020, 07:32:39 pm
content: Since I use a PCB as front panel, I'd like to route little tongues in my pcb, these tongues would be above tact switches to provide a larger surface for the user to press.To give a better feeling, i'd like to have the center of each routed button higher than the PCB surface.I'm searching for metal "things" that comes in reels, that could be placed like any other component except that it's not really a component, just a metal piece... (super nice if available in different colors).Does that exists ?

author: Clear as mud
author_rank: Regular Contributor
timestamp: June 20, 2020, 07:47:10 pm
content: Can you draw a picture of what you want? I am having trouble envisioning it.

author: ratatax
author_rank: Regular Contributor
timestamp: June 20, 2020, 08:17:44 pm
content: Does that helps ?

author: ratatax
author_rank: Regular Contributor
timestamp: June 20, 2020, 08:18:56 pm
content: Somthing the size of a sop-8 IC would be ideal, adds like 1mm thickness on a small rectangle area...

author: piguy101
author_rank: Regular Contributor
timestamp: June 21, 2020, 01:07:33 am
content: The best I can find is the 5108 jumper from Keystone. It is basically just a piece of silver plated copper and stands 0.71 mm above the PCB. It is the the same footprint as a 1206 resistor.Digikey appears to stock a bunch with a MOQ of 1. Mouser's website is working and here is a link:https://www.mouser.com/ProductDetail/Keystone-Electronics/5108?qs=%2Fha2pyFadui6SmzJnW0ch%2FdohwQUP57VMo3W%2FtqHRS%252B%252BZhEJKafa2Q%3D%3DAre you sure the tongue idea works? PCBs are still I can't imagine them bending much for a button.

author: Clear as mud
author_rank: Regular Contributor
timestamp: June 21, 2020, 03:20:13 am
content: Maybe you could get some very small squares of PCB material, with different colors of soldermask, and just glue them onto your tabs. Or solder them on, if you had footprints that matched.Why not just use colored acrylic sheets and glue them on?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 21, 2020, 06:42:06 am
content: There are probe points which are little more than solid tabs of metal:https://www.mouser.com/ProductDetail/Mill-Max/1578-3-57-15-00-00-03-0?qs=LmpLwp9g96nNqYYaIPJAsA%3D%3Dhttps://www.mouser.com/ProductDetail/Mill-Max/1559-1-57-15-00-00-03-0?qs=%252BEew9%252B0nqrDJg2xoDKXwZQ%3D%3DFor something softer, how about rubber feet?https://www.digikey.com/short/zhnc5zMind, the adhesive probably goes gooey after some time, especially with grubby fingers touching it. The parts themselves seem like a good idea, maybe they can be found with a better adhesive.Tim
SMD reflow temperatures? - Page 1
Forum section: electronics / beginners

author: peps1
author_rank: Regular Contributor
timestamp: June 06, 2013, 12:19:37 am
content: Hey guys, just got one of the cheap YIHUA reflow workstations, and was wondering what temps I should be work with on SMD?

author: EEVblog
author_rank: Unknown
timestamp: June 06, 2013, 01:32:20 am
content: Try 280 for starters. I wouldn't usually don't need to go over 300, but it is highly variable and depends on the thermal mass of the component and pads etc, lead or lead free solder, nozzle size, your technique etc etc

author: peps1
author_rank: Regular Contributor
timestamp: June 06, 2013, 01:41:46 am
content: Thanks mate,Was testing it on some scrap PCB full of 1206 package caps at 300 Celsius (default heat) and it was just flowing in seconds, so guess dialing it back to 280 or less makes sense, if I don't want to damage anything! (It's a really fun bit of kit!)Now I have Just enough knowledge to be dangerous!

author: Falcon69
author_rank: Super Contributor
timestamp: June 07, 2013, 09:09:00 pm
content: Make sure your components can handle it. I had some 3.5mm stereo jacks, along with some resistors and caps that needed to be reflow soldered. I was watching it through the window as it was heating up. Before all the solder even began to melt and flow, the stereo jacks started melting.

author: amyk
author_rank: Super Contributor
timestamp: June 08, 2013, 12:52:17 pm
content: Sorry if you know this already but since this is the beginner's forum I'll mention that unlike the heat of a soldering iron, the air from the gun does travel some distance so you'd best mind where it's pointing if you don't want to accidentally melt/burn things.

author: millerb
author_rank: Regular Contributor
timestamp: June 08, 2013, 01:06:09 pm
content: Quote from: amyk on June 08, 2013, 12:52:17 pmGood advise. I bought an 18"x18" ceramic tile from the hardware store for 4 dollars, and I set that on my desk when I'm using the hot air tool so I don't burn anything. I keep a fire extinguisher near by just in case. I have the SMD station plugged into one of those "energy saving" power strips, where it only provides power to the outlets when one specified outlet is drawing current. On that specified outlet I have a desk lamp. This way the SMD station can only be powered up if the desk lamp is on. Can't be too careful in the electronics dungeon.
SMD Resistor Array/Network sizes - Page 1
Forum section: electronics / beginners

author: bitman
author_rank: Unknown
timestamp: May 28, 2020, 08:11:54 pm
content: I'm trying to understand the physical sizing of SMD Resistor Arrays. I thought the usual SMD sizing codes like 1206 would be used for these components too, but I'm finding that's not the case. A 1206 Resistor network/array is larger than a 1206 resistor. I grabbed a random DataSheet from Digikey to see if it would help me - but I'm just even more confused now:https://www.yageo.com/upload/media/product/productsearch/datasheet/rchip/PYu-YC_TC_group_51_RoHS_L_9.pdfI've never seen these codes before. Are this not standardized so size specification differs between vendors? I have a resistor arrays that were marked 1206 but as I stated are bigger than 1206. It almost looks like the 1206 marking is as if you would place X number of 1206 resistors side by side to get the array size?If there's somewhere I can go to learn about the sizing of these components I would like to know. I thought I had what I needed using the usual SMD codes for single caps, resistors, inductors ... alas, I'm wrong.
smd resistor marked only with an S - Page 1
Forum section: electronics / beginners

author: paulhm81
author_rank: Regular Contributor
timestamp: June 16, 2014, 06:30:13 pm
content: HelloI have a dead hitachi hdd and on the power input side of the electronic board there is a black smd like a resistor and the only marking on it is an S. Does anybody know what that should be? I forgot to take a picture and I didn't get to look what's it's purpose in the circuit because I only took a quick look at it and I had to go. I took a quick measure on resistance and there was nothing. My dmm's limit is 40M. I"m hoping it's a fuse resistor.

author: idpromnut
author_rank: Unknown
timestamp: June 16, 2014, 06:57:23 pm
content: Sounds very much like a poly fuse (I assume by measuring "nothing" on resistance, you mean it was a dead short).

author: paulhm81
author_rank: Regular Contributor
timestamp: June 16, 2014, 07:36:36 pm
content: actually by nothing I meant it was open.

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 16, 2014, 07:44:58 pm
content: There are smd fuses with single letter markings, the most common mentioned are the ones you find on inverter boards in digital tv's , there normally marked P.If you do a search for something like 'smd fuse P inverter board', you will find data sheets showing what the letters represent in regards fuse rating.Here you are, did a quick search, look at page 3http://www.farnell.com/datasheets/1662505.pdf

author: paulhm81
author_rank: Regular Contributor
timestamp: June 16, 2014, 07:51:59 pm
content: thank you for the input. S seems to be 4A. I will look more carefully tomorrow if it really is placed as a fuse because 4A seems huge for a 2.5 hdd.Thank's again!
SMD resistor nominal value variation after reflow - Page 1
Forum section: electronics / beginners

author: lilmantis
author_rank: Contributor
timestamp: October 28, 2015, 11:27:36 am
content: Does anyone know anything about SMD resistor nominal value variation after reflow? How much does value change?

author: coppice
author_rank: Super Contributor
timestamp: October 28, 2015, 11:31:54 am
content: Quote from: lilmantis on October 28, 2015, 11:27:36 amIt depends a lot on the particular part. However, unless the soldering was really brutal, over the first few days after soldering components usually drift most of the way back to their original value.

author: lilmantis
author_rank: Contributor
timestamp: October 28, 2015, 01:02:44 pm
content: So usually the value is not permanently affected?I remember reading somewhere about this effect in precision circuits.

author: poorchava
author_rank: Super Contributor
timestamp: October 28, 2015, 01:32:54 pm
content: IIRC J-STD-020, which is often regarded as a base line when it comes to soldering stuff specifies that component should be in spec after 3 reflow cycles (two sides of the PCB + rework after poor reflow).Sent from my HTC One M8s using Tapatalk.edit: the area where this does not necessarily apply is very high precision stuff like for example LTZ1000 or some high precision oscillators.
SMD Resistor Value - Page 1
Forum section: electronics / beginners

author: higginsdj
author_rank: Contributor
timestamp: April 30, 2025, 04:25:09 am
content: I am trying to determine the actual value of a resistor marked "R04F". Google AI varies from 400mOhm to 40Ohm but it actually measures 40mOhm on a Multimeter and 2 LCR meters out of circuit.

author: SuzyC
author_rank: Frequent Contributor
timestamp: April 30, 2025, 05:28:21 am
content: Trust your meters. R04 is .040 ohm 40milli-ohm

author: u666sa
author_rank: Frequent Contributor
timestamp: April 30, 2025, 11:39:33 pm
content: Current sensing .04 ohm

author: MrAl
author_rank: Super Contributor
timestamp: May 05, 2025, 08:06:57 am
content: Quote from: higginsdj on April 30, 2025, 04:25:09 amHi,I believe the "R" is the decimal point, and the "F" is 1 percent tolerance. That makes the value 0.040 Ohms, 1 percent tolerance on the value. Not sure of the wattage offhand, you could take a photo of a known wattage resistor side by side with this one and we can compare, and compare the thickness too. Ultimately, you could test it for wattage too.The meters seem to agree on 0.040 Ohms also.If you still have doubts, if you have another 40mOhm resistor laying around you could check it with the meters and see if they read the right value for that one too.How did you get that thing out of circuit, you unsoldered it already?

author: higginsdj
author_rank: Contributor
timestamp: May 07, 2025, 01:00:13 am
content: Yes, not too hard to remove with hot air.

author: langwadt
author_rank: Super Contributor
timestamp: May 07, 2025, 01:06:51 am
content: Quote from: higginsdj on April 30, 2025, 04:25:09 amand you doubt who is right? it's a joke right?

author: TimFox
author_rank: Super Contributor
timestamp: May 07, 2025, 01:20:43 am
content: “R” for decimal point (as in “radix point, q.v.) is common, and “F” is the standard code for 1%, as Mr Al pointed out above.Experience beats AI: surprise!

author: higginsdj
author_rank: Contributor
timestamp: May 07, 2025, 06:24:36 am
content: That's why I am asking here!
SMD RGB LED Packages - Page 1
Forum section: electronics / beginners

author: meander
author_rank: Newbie
timestamp: March 12, 2016, 05:04:59 am
content: do any of you have any idea what package this is? its an SMD RGB LED, but i have never been able to find a similar package. it appears to have metal around the lens, presumably for better heat dissipation, all the ones i find are round, entirely plastic, or both. Thanks for the help!

author: michaeliv
author_rank: Frequent Contributor
timestamp: March 12, 2016, 10:09:59 am
content: A suggestion is to measure the dimensions precisely using a micrometer. Then search AliExpress/eBay for "XXYY" led. Then look at the specs if you do manage to find one.
SMD shaft pot - Possible? - Page 1
Forum section: electronics / beginners

author: made2hack
author_rank: Frequent Contributor
timestamp: July 01, 2015, 06:39:26 pm
content: Hello,So I'm essentially looking for a shaft potentiometer but that is surface mount. I don't really want to mount a large TH pot by just soldering the tabs to the board.Ideally, I would like the low profile of an SMD trimmer but with a shaft. Do they exist? Looking on the suppliers website, doesn't really seem to.This is what I would ideally want:I found the trimmer knobs but I want to know if they are compatible so that once stuck to the trimmer, they would make essentially a shaft. I'm not looking for a trimmer tool. The example above probably would not work but you get the idea what I want to achieve.Here's a list of TME'strimmer knobs.

author: Ian.M
author_rank: Super Contributor
timestamp: July 01, 2015, 07:46:05 pm
content: JFGI - image search for: SMD potentiometer

author: Mr.B
author_rank: Unknown
timestamp: July 01, 2015, 07:55:53 pm
content: I have used Bourns before.Datasheet of what I used below.Mouser currently carrying 10K and 50K linear.

author: dadler
author_rank: Unknown
timestamp: July 01, 2015, 08:35:14 pm
content: These are through-hole but pretty small:http://www.taydaelectronics.com/potentiometer-variable-resistors/rotary-potentiometer/linear/1k-ohm-linear-taper-potentiometer-round-knurled-plastic-shaft-pcb-9mm.html

author: Richard Crowley
author_rank: Super Contributor
timestamp: July 01, 2015, 09:14:57 pm
content: Yes there are several products from several vendors.Google image search turns up many candidates if you search for: smd potentiometer
SMD stencils - Page 1
Forum section: electronics / beginners

author: rthorntn
author_rank: Frequent Contributor
timestamp: May 30, 2018, 02:19:58 am
content: Hi All,I have a laser cutter, the Darkly Labs Emblaser, 4w laser power from memory.I want to cut solder paste stencils with it, any tips, tricks and/or recommendations?It looks like thick 0.127mm (5 mil) Polyimide (Kapton) film is popular for this, if it makes sense does anyone have a cheap source for this?The vendor mentioned to me that thin Kapton tape doesn't work well because of over-burn which makes sense.In the vendor forums someone mentioned using overhead projector transparencies but his last post was about having to play with the power/speed to get the best results.Thanks for looking.CheersRichard

author: JS
author_rank: Frequent Contributor
timestamp: May 30, 2018, 03:47:50 am
content: Mylar maybe? Used to insulate electric motor windings is easy to get where you get coil wire and other electric motor related parts. Should be quite cheap for the application, it does handle temperature very well but I don't know how it will behave with the laser.JS