hybridfree/eevblog-posts huggingface dataset:
Dilemma: shrouded header 2x4 pin  - Page 1
Forum section: electronics / projects

author: tiborsimon
author_rank: Contributor
timestamp: May 24, 2014, 11:01:30 am
content: Hi guys!It seems to me that the 2x4 pin shrouded headers are really rare parts (at least in Hungary). Do you think it is worth to design a product with these headers?

author: David_AVD
author_rank: Super Contributor
timestamp: May 24, 2014, 11:04:46 am
content: Connectors like that with less than 10 pins are way more expensive and really hard to find in small quantities.If you have the space for the 10 pin version (2x5) you should go with that instead imo.

author: tiborsimon
author_rank: Contributor
timestamp: May 24, 2014, 11:13:08 am
content: Yeah, I am using 10 pin headers in the current revision. Thanks for the advice

author: Monkeh
author_rank: Super Contributor
timestamp: May 24, 2014, 11:34:50 am
content: Of course, if you can use slightly larger quantities:http://www.aliexpress.com/item/100PCS-Box-headers-DC3-8P-2-54mm-straight-IDC-Box-headers-connector-8Pins-2x4-DIP/1519079557.html

author: ajb
author_rank: Super Contributor
timestamp: May 24, 2014, 07:54:37 pm
content: I've found Wurth to be reliable for this sort of thing. 8 pin shrouded headers are a standard part, so they should have them in stock with no MOQ. Not sure how they are with hobbyists, if that's your situation, but our local rep has been happy to sell us 25-100 parts at a time.

author: David_AVD
author_rank: Super Contributor
timestamp: May 24, 2014, 11:14:56 pm
content: That's a good price from that Aliexpress seller. Just make sure you can get the matching cable crimps at a reasonable price.

author: tiborsimon
author_rank: Contributor
timestamp: May 25, 2014, 07:16:08 pm
content: Thank you guys for the answers. I realized, that I can fit in a 2x3 header too, which isn't as rare as the 2x4, so I would pick that.I have another question. What are the benefits of a shrouded header? Do they worth the extra space? In my project I want to chain individual boards to each other. The headers and the corresponding plugs and cables will implement a common bus. It will be a modular human interface, so the connectors may get loose. But as I tried, the shrouded connectors get loose too. I used standard plugs/crimps and shrouded headers.

author: Monkeh
author_rank: Super Contributor
timestamp: May 25, 2014, 07:17:31 pm
content: Keying.
Dilemma - which connector for supply side power ex bicycle dynamo - Page 1
Forum section: electronics / projects

author: Daksol
author_rank: Newbie
timestamp: June 04, 2023, 11:06:50 am
content: Interesting dilemma I have encountered wrt orientation M vs F of a low voltage connector.I am setting up some wiring on a bicycle which will include a bicycle hub dynamo, lights powered by dynamo, rechargeable batteries, USB sockets for recharging electronica.There is one location on the dynamo side of things where I want to have a waterproof connector which can easily be connected/disconnected. Dynamos generate about 6 VAC, 3W - so low voltage, low current. There are (afaik) no established standards used in this space for such a connector (apart from maybe SON who have expensive coax connectors).I was pleased to find an option from my local supplier which is inexpensive, waterproof, latches, easily connect, etc. See photo. The two connectors are supplioed with short cables, are secured witha locking ring, and are waterproof enough for this application. The male connector is dimensionally the same as a conventional barrel jack 5.5x2.1mm.The question arises then - do I connect the male or the female to the supply (dynamo) side?** If I follow the convention from devices powered via a barrel jack, the male should be the supply.** But if an ISO-standard Martian was to look at this - they would say that the female is the obvious choice to be the supply, given that it is shrouded, no conducting material sticking out.So what is the correct option here?(One point of reference is a cheap solar lighting string ex Ikea using same connector - they use female on supply side)
Dim bulb tester - totally enclosed, with switchable cooling fan - Page 1
Forum section: electronics / projects

author: eblc1388
author_rank: Frequent Contributor
timestamp: August 09, 2020, 10:52:17 am
content: I would like to share with a you a very useful gadget in testing and repairing. I made mine using three halogen lamps with rating of 75W, 150W and 300W. I choose halogen lamps as their size are small and still widely obtainable. However, it might be difficult to get the specific wattage required. They are mounted onto ceramic lamp holders because of the possible high temperature. The internal wirings are done using silicone cable. The whole circuit fitted inside a server power supply case as shown.Using three separate switches, the combination of the lamps offer a wattage range from 75W to 525W with steps of 75W. An additional three-position switch is also added for switching an internal 12V fan or bypass the lamps all together.If you are thinking of making one but have not yet committed to, at least gather all the lamps first when they are still easily available.You can can also add an extra 500W lamp to the combination to get more wattage ranges.

author: wizard69
author_rank: Super Contributor
timestamp: August 10, 2020, 04:32:07 pm
content: Cool, but how do you see the bulbs in operation?

author: SeanB
author_rank: Super Contributor
timestamp: August 10, 2020, 06:28:43 pm
content: I would assume through the numerous cooling areas of the case, as only a bright lamp will provide visible light.
dim bulb tester - Page 1
Forum section: electronics / projects

author: manicdoc
author_rank: Unknown
timestamp: February 21, 2024, 07:11:11 am
content: Just a dim bulb tester I put together, there was an earlier version but the bulbs were on top, so it wasn't stackable, plus I couldn't see what the power draw was easily and if it was stable/as expected.The meter is a unit I got off aliexpress, measures voltage, current, power factor, frequency, power, etc - plus sums over time. The two small switches cut in the bulbs, so I have a choice of 40w,100w or 140w before it cuts in and saves the DUT. The banana socket is to Earth via a 100k resistor, so can be used for static suppression if needed (although never been a problem). The box is one I put together out of offcuts I had lying around, so its ended up built a bit like a brick dunny!The device stacked atop is a Keithley 2000 that I fixed (someone had a go at it before and their soldering and diagnosis wasn't up to it). To the right is a HP func gen and a Agilent DC source/battery simulator in effect, both I fixed as well (bad contacts on the HP and a bolt in the wrong place on the Agilent...). To the right is a dual rail bench power supply (built from a kit) and a Rigol 4 channel oscilloscope.

author: MarkF
author_rank: Super Contributor
timestamp: February 21, 2024, 01:04:44 pm
content: See what others have done:https://www.eevblog.com/forum/beginners/dim-bulb-current-limiter-prototype/

author: manicdoc
author_rank: Unknown
timestamp: February 22, 2024, 02:54:47 am
content: Thanks for that, I see some people have really gone to town on it. In my case I wanted something that fitted in, dimension & stack-ability wise, with the other kit.
Dimensioning of hot plate and heater cartridge - Page 1
Forum section: electronics / projects

author: Javier
author_rank: Contributor
timestamp: February 24, 2015, 08:30:17 am
content: Hello all,does someone have a reference for the dimensioning of a hot plate and heater cartridge system? I'm thinking along the lines of an application note that explains, give a hot plate of so and so square cms and a cartridge of so and so Watts then it takes so many seconds to reach Temperature X.I couldn't find such an analysis anywhere and the approach "drill a hole in an aluminium block and hope for the better" stresses me a little bit.Cheers and many thanks in advance

author: Pjotr
author_rank: Frequent Contributor
timestamp: April 03, 2015, 09:53:54 am
content: Hi Javier,Currently I am working on a small hotplate for small SMD boards myself. The plate itself acts as a large thermal capacitor (>= 1K equivalent Farads if you can say so) fed with a thermal current (power). Which gives an almost linear rising temperature over time if not controlled, according to the following formula:thermal_mass X temperature rise = power x timeWhere thermal mass = specific heat X massIn parallel to the thermal mass there is the heat loss to the surrounding which acts as a thermal resistance in parallel to the thermal capacitor. This resistance is mostly relatively large for a hotplate, 0.5 degK/W to 5 degK/W or so.Here is a good explanation of the thermal metrics you are looking for:http://www.turk-hillinger.us/fileadmin/media/pdfs/berechnungsgrundlagen.pdfIt is in German but hopefully you get some understanding. It also shows graphs of maximum play of cartridge heaters related to the surface load (watts/cm2) of the cartridges.
Dimensions of DC barrel power jack compatible with 5.5mm, 2.5mm male connector - Page 1
Forum section: electronics / projects

author: sabiha
author_rank: Newbie
timestamp: May 11, 2018, 02:26:48 pm
content: Hello,I would like to know the dimensions of female DC barrel power jack compatible with a male connector of 5.5mm OuterDia;2.5mm InnerDia.Find the attached male connector and female barrel jack for the reference.Please help me in this regard.Thank you.

author: sokoloff
author_rank: Super Contributor
timestamp: May 11, 2018, 04:41:23 pm
content: Quote from: sabiha on May 11, 2018, 02:26:48 pmYour question seems to assume that there is *ONE* answer. There are a variety of manufacturers and each is likely to be slightly different.I'd go find a matching part (sample:https://www.digikey.com/product-detail/en/cui-inc/PJ-037B/CP-037B-ND/1644546) and look over the datasheet and/or CAD model for the specific part that you're going to use.
Dimmer and digital voltmeter - Page 1
Forum section: electronics / projects

author: fx991ex
author_rank: Contributor
timestamp: February 27, 2023, 09:36:57 am
content: I am building voltage regulator for an IR heater.Before I order parts from Aliexpress and wait a month I would like to know if I can even measure the output voltage of a dimmer with a voltage indicator and get an accurate reading (links to both products are below).https://www.aliexpress.com/item/1005004564131676.html?spm=a2g0o.cart.0.0.2ceb38daSCJUxN&mp=1https://www.aliexpress.com/item/33000442850.html?spm=a2g0o.productlist.main.1.70fa4ffaUmJhLi&algo_pvid=7c1c176b-f0c0-4966-814b-70331cab0f94&algo_exp_id=7c1c176b-f0c0-4966-814b-70331cab0f94-0&pdp_ext_f=%7B%22sku_id%22%3A%2266972885481%22%7D&pdp_npi=3%40dis%21EUR%211.56%211.48%21%21%21%21%21%402102160416774856994718058d074f%2166972885481%21sea%21SI%21737130228&curPageLogUid=pHNk0GgcXNOE

author: Gyro
author_rank: Super Contributor
timestamp: February 27, 2023, 10:05:58 am
content: The dimmer module, as you probably know, is SCR based. It varies it's output by switching on at a variable point in the mains cycle. The meter is probably peak reading, calibrated to display an RMS equivalent reading for a pure a sine wave' (I don't think there is any chance of it being true RMS detecting at that price).The resulting reading is likely to be very non-linear - it might well not register any significant change in reading until you get beyond 50% dimming, ie. when the SCR doesn't turn on until after mains peak.
Dimmer for an aspirator (evaporative cooler) - Page 1
Forum section: electronics / projects

author: woor90
author_rank: Newbie
timestamp: May 11, 2019, 08:31:21 pm
content: Hello,I have an evaporative cooler which is too noisy for the application I want to use it for, I'd like to ask if it's possible to use a dimmer for it in order to drastically reduce the noise. Of course I'm aware that decreasing the fan speed will decrease the efficiency of the device, but this is not a problem at all, it's already oversized. My issue is only the noise (around 60dB at minimum...).In particular I'm talking of this device:https://www.honeywellstore.com/store/products/evaporative-air-cooler-for-indoor-outdoor-and-commercial-honeywell-co60pm.htmI know there is also a water pump inside, but I can simply disconnect it and run it separately.Do you think it's a feasible workaround?Will decreasing the speed to 1/2 or 1/3 of the selectable lowest speed significantly decrease the noise?Which type of dimmer do I need? one for induction motors, right?Thanks

author: soldar
author_rank: Super Contributor
timestamp: May 11, 2019, 09:00:08 pm
content: The description says it has three speeds. Even the lowest is too noisy for you?

author: woor90
author_rank: Newbie
timestamp: May 11, 2019, 09:40:32 pm
content: Yes, it's too lout even at low speed.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 12, 2019, 01:12:30 am
content: Get a ceiling fan speed controller.

author: soldar
author_rank: Super Contributor
timestamp: May 12, 2019, 06:20:03 am
content: While an electronic controller might work you could try something simpler which is inserting a resistor in series (suitably sized in every respect).
Dimmer Rheostat is buzzing - Page 1
Forum section: electronics / projects

author: justin66
author_rank: Regular Contributor
timestamp: March 28, 2016, 07:44:50 pm
content: hey guys i have bought light controlling rheostat witch is rated for 250v 50hz 400w i have halogen lights witch is 140w each @ 220v so total load is 280w when i turn on the lights it makes buzzing sound sounds kinda like switching sound but it barely change when adjusting it. how do i fix this?no its not the chokethe sound is recorded here. sounds like 50hz ??http://vocaroo.com/i/s139cagvAcIj

author: SeanB
author_rank: Super Contributor
timestamp: March 28, 2016, 08:08:06 pm
content: Magnetostriction in the choke core. No real cure aside from a less magnetostrictive core, and that will not fit in the volume of the existing choke. You can dip it in polyurethane varnish to make it a little quieter, but they all buzz.

author: justin66
author_rank: Regular Contributor
timestamp: March 28, 2016, 08:59:21 pm
content: thanks
Dimming meanwell led driver - Page 1
Forum section: electronics / projects

author: daniel444
author_rank: Regular Contributor
timestamp: February 06, 2019, 02:55:55 am
content: hiso ive been building some cob led lamps with Chinese boost drivers and they worked out quite wellnow ive upgraded to a meanwell dc to dc boost driver LDH-45 , seems to be the only brand name boost driver on the marketit has a dimming function but it requires voltage or pwm input , not a simple 10k pot that would make for a neat buildi have bought a tiny module that outputs 0.8v , this activates the dimming but not down to a low enough level , it seems i need 0.25v to get full dimmingi dont know how to get the 0.25v i needi dont want to use a bulky ebay pwm module , and the requirements seem to specify a certain type of pwm anywayany ideas ??

author: daniel444
author_rank: Regular Contributor
timestamp: February 06, 2019, 02:57:00 am
content: here is a picture of the lamp i built

author: MarkF
author_rank: Super Contributor
timestamp: February 06, 2019, 05:02:40 am
content: I'm not familiar with these.But, isn't as simple as adding a pot and resistor???

author: daniel444
author_rank: Regular Contributor
timestamp: February 06, 2019, 05:35:31 am
content: thanks!your suggestion has workedi didn't realize it was so simple

author: DaJMasta
author_rank: Super Contributor
timestamp: February 06, 2019, 05:51:26 am
content: They make them to be easy! If you want digital control instead, you just feed your PWM signal into the relevant terminal.

author: MarkF
author_rank: Super Contributor
timestamp: February 06, 2019, 05:51:54 am
content: Remember you need to select the resistor and pot values to limit the input to 1.2V for Analog DIM pin.
Dimming with Constant Current LED Power Supply - Page 1
Forum section: electronics / projects

author: lmagalhaes
author_rank: Contributor
timestamp: July 08, 2020, 03:18:03 pm
content: Hey there,I have a HLG-320H-C700B LED Power supply and I wanted to have a custom PCB with 4 rows of LEDs of different colors. Then, I'd like to have 4 controls of 0-10V to dim each row individually. Is this at all possible?With an opamp sensing a resistor on the beggining of each LED string would this be possible? I'm not used to working with constant current supplies. How would it handle this situation ? How would it determine the output voltage ? Would adding another resistor in order to drop the remaining voltage be enough ? It has a maximum of 700mA in total, but they could be distributed, in theory, in anyway for those 4 LED rows right?Let me know if I'm just wasting time trying to figure this one out.Luís

author: Marco
author_rank: Super Contributor
timestamp: July 08, 2020, 10:58:50 pm
content: This is just making life unnecessarily hard on yourself, use a constant voltage power supply and 4 adjustable buck led drivers.
Dims for Novar & Compactron sockets? - Page 1
Forum section: electronics / projects

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: September 10, 2017, 05:52:55 pm
content: Does anyone have the outer pin circumference & pin diameter for both the Novar and Compactron ceramic sockets sold on eBay? My in town suppliers are closed today and tomorrow pending the end of the world here in Florida.So I don't waste 2 good snowdays, so I thought I'd draw up some libraries for the sockets, that is if tomorrow still is comming..

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: October 25, 2017, 10:30:28 am
content: Finally had to order some and they arrived from China China China. No need for further assistance.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 25, 2017, 04:00:43 pm
content: Well, the tubes themselves are here,https://en.wikipedia.org/wiki/Tube_socket#Summary_of_base_detailsas for the sockets, you'd have to ask the manufacturer for a drawing. The pin tails could be kinked inside or outside, alternating or straight, whatever width...Nice thing about pin-base tubes is, if you can't find a socket, you can always make your own with solder-in socket pins in a PCB. Not the best voltage rating, or least capacitance, but can be handy in a pinch, especially for oddballs like Nixies.Tim
DIN 010599 6-way Right Angle PCB Pin numbering - Page 1
Forum section: electronics / projects

author: NivagSwerdna
author_rank: Super Contributor
timestamp: October 05, 2020, 02:34:23 pm
content: As part of my latest gadget I need a 6-way DIN socket and found this one...https://docs.rs-online.com/1775/0900766b8147289a.pdfThe footprint shows the holes but doesn't number them? Am I missing something?(Ideally I would do the PCB layout before actually ordering them and having one in my hand)

author: NivagSwerdna
author_rank: Super Contributor
timestamp: October 05, 2020, 03:55:16 pm
content: I think it is something like this... Footprint is looking down onto PCB

author: perdrix
author_rank: Frequent Contributor
timestamp: October 05, 2020, 08:19:44 pm
content: Here's the footprint pin numbers -Din Pin mapping to footprint pins:P1 3P2 5P3 2P5 1P4 4P6 8P7 6,7David
DIN 41612 H15 'power-DIN' standard? - Page 1
Forum section: electronics / projects

author: awallin
author_rank: Frequent Contributor
timestamp: May 12, 2020, 05:18:32 am
content: Is there a recognized standard for 19" plug-in powersupplies using DIN 41612 H15 'harting' or maybe 'power-DIN' 15-pin connectors?Looking at datasheets for PSUs, the bottom pins are consistently PE, N and L, but the DC-connections seem to vary a lot??see e.g. schroff cataloghttps://schroff.nvent.com/wcsstore/ExtendedSitesCatalogAssetStore/Attachment/SchroffAttachments/09_e_psu.pdfI'm designing a rack for various analog boards (100x160 eurocard) and looking for some minimal backplane solution... mostly just +/-15 V or +/-12V needed for all boards.thanks,A
DIN rail mount programmable power supply - Page 1
Forum section: electronics / projects

author: Dr_Neoo
author_rank: Contributor
timestamp: December 05, 2023, 11:36:35 pm
content: Hello all,I'm trying to find if there any of the shelf DIN mount/small formfactor progamable power supplies. 0-30 V and 1A would be ideal but down to 0V is not a hard requirement. Control could be anything from analog input to USB as long as it can be automated.So far I have mostly found stuff like NI Pixi modules or larger standalone lab power supplies. There is also a module from beckhoff that looks interesting but it is not released yet:https://www.beckhoff.com/en-en/products/i-o/ethercat-terminals/el9xxx-system/el9501.htmlI could design a custom solution but I thought that checking here for suggestions first would be a good idea ( don't need more new projects... 😉)

author: pqass
author_rank: Super Contributor
timestamp: December 06, 2023, 01:21:45 am
content: Thisclipshould expand the field of possibilities.

author: Terry Bites
author_rank: Super Contributor
timestamp: December 07, 2023, 04:38:32 pm
content: I think that will cost you serious cash. Its a bit niche.You may want to (reluctantly) use a separate USB DAC and use the output to program a simpler analog programmed PSU module. This kind of thinghttps://www.lucid-control.com/product/lucidcontrol-ao4-4-channel-analog-output-usb-module/I'm sure there are chaeper versions. Or possibly use an RS232 prog'd psu with ahttps://www.secomp-international.com/en_US/roline-usb-2-0-to-rs232-adapter-for-din-rail-1-port/i/12.02.1001-4or similar

author: linux-works
author_rank: Super Contributor
timestamp: December 07, 2023, 04:59:32 pm
content: how about opendps as the software and this as the hw:amazon.com/dp/B09B1NW9NH(dps5005 series).I have some small boxes that are 3d printable that fit this. you could adapt that for din rail use.its fanless and it just takes a dc input (wall wart). and yes, its remote controllable (I'm working on a fork that expands a bit on the opendps firmware).if you get the module that has both serial interfaces (bt and usb) then you can pick what you want. use an hc05 since I think the bt interface is classic and not ble (else, use an hm10 or similar for the pc side).there is a cli util for linux (source) that will get/set values via simple .c program.(I'm actually going to be updating my github with this info shortly)I have used these psu's for a few years now and they are quite nice for the price and remote control ability. and being fanless helps, too.

author: linux-works
author_rank: Super Contributor
timestamp: December 07, 2023, 05:03:24 pm
content: main github site:https://github.com/kanflo/opendpsthe author has not updated things in a while and seems to have given the project all he intends (which was a huge amount!)I'm adding some more features, myself, but just some minor updates.go to that main site, first, to see what its about.
Diode Bridge as a Switch ? - Page 1
Forum section: electronics / projects

author: Swaroop 21
author_rank: Regular Contributor
timestamp: August 08, 2024, 01:33:21 pm
content: I have to turn the spot lights in my balconies on/off I am looking for a way to switch them without using relays. One way is to use TRIACs, while I was looking up for the methods I came across a method where they use a IGBT or some switching device across the output of a Diode Bridge.I have never used it before so what are the things I should consider if I want to use this ? The lights are low power just 5W at 230V.To turn them on or off with just a digital Signal from a RF receiver circuit with HT12D. Can I use SCR or MOSFET rated for high voltage ?

author: tooki
author_rank: Super Contributor
timestamp: August 08, 2024, 01:56:44 pm
content: Just to be clear, when using this circuit, the nodes that you’re calling the “output” (because they would be, if using the bridge as a rectifier) are not the output of the circuit. The AC “inputs” of the bridge are put inserieswith the AC line.But for simple on/off control, why not use a relay? And if not a mechanical relay, why not use a TRIAC or an SSR?

author: Swaroop 21
author_rank: Regular Contributor
timestamp: August 08, 2024, 02:55:26 pm
content: Quote from: tooki on August 08, 2024, 01:56:44 pmI am sorry I didn't mean to say the output of the circuit rather I wanna point out the placement of the switch.And the reason for not using relays is because of space constrains, although relays are small but to drive them I will need a few 10mA for which I would require a good sized capacitive dropper hence I am looking forward to use this kind of solid state switching mechanism. Secondly I can use TRIACs but at this moment I ran out of those MOC3083 Optos. So I was just wondering about to look for another way and came across this so as I had the required things I thought about asking it here because I am not sure how it will behave with the LED SPOTLIGHTs. If this ain't a good solution I would just have to wait until the MOC3083's arriveNothing wrong with the relays too but just want to know about this circuit, might be useful in future ?
Diode Cut Desgin Considerations - Page 1
Forum section: electronics / projects

author: ThatElectronicsGuy
author_rank: Newbie
timestamp: October 05, 2025, 02:11:02 pm
content: Hi, I have problem with implementation of the circuit shown below in attachment. The idea is to cut everything that is above 0V level and pass through only negative peaks, while compensating 0.5V drop on diode. Components used are different than in simulation but it shouldn't be a problem (the opamp is LT1365 and the diode is 1n4148). Simulation works. However on breadboard it's not quite working. I'll attach simulation graph and scope graph (with original wave in blue colour (little bit offsetted because of scope probe)). From what I understand, amp is blocked on the positive half and goes sky high because of that, but I cannot come up with working workaround for that.How can I improve design here? I've seen also precision half wave rectifier but I don't think that's what I search for - I want to have the wave on the negative side here without inverting, because it causes not necessary delays and costs.

author: moffy
author_rank: Super Contributor
timestamp: October 05, 2025, 02:45:33 pm
content: Is this what you want? The extra diode prevents the opamp slewing to the opposite rail.

author: ThatElectronicsGuy
author_rank: Newbie
timestamp: October 05, 2025, 03:02:09 pm
content: Yeah, that's what I wanted. I'll try it on breadboard.
Diode datasheet - so which is A and which is K? - Page 1
Forum section: electronics / projects

author: Circlotron
author_rank: Super Contributor
timestamp: July 21, 2016, 02:03:03 am
content: http://www.smc-diodes.com/propdf/SDUR6030W%20N1270%20REV.-.pdfThe drawing has no labels for A and K or 1 & 2.I would presume the pin that also connects to the centre leg is the cathode because it connects to the heatsink surface like a double diode common cathode does.

author: Audioguru
author_rank: Super Contributor
timestamp: July 21, 2016, 02:22:49 am
content: Missing important information. What do you expect? it is Chinese. The person translating the datasheet into Engrish knows nothing about electronics.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: July 21, 2016, 02:34:37 am
content: Maybe they "assume" that the prospective user knows that the Pin 1 of a TO-247AC package is the one on the left as you view the front of the package.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 21, 2016, 03:40:27 pm
content: Radial packaged diodes (including TO-247 and 220 styles) are usually anode on right, cathode on left (viewed from front, leads down).It could always be reverse polarity, so if you must use it, get samples first...Tim

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 21, 2016, 03:51:50 pm
content: to where the red probe read 0.7V
diode datesheet / and or cross ref. - Page 1
Forum section: electronics / projects

author: whitevamp
author_rank: Regular Contributor
timestamp: May 16, 2017, 03:40:57 pm
content: ok so i have some nos tektronix diodes 152-0107-00 and from what i have found they cross over to a G727 from Texas Instruments but i can not find any data sheet on this diode.dose any one know where a data sheet can be found?and or what the G727 crosses over to?

author: edavid
author_rank: Super Contributor
timestamp: May 16, 2017, 04:04:07 pm
content: Quote from: whitevamp on May 16, 2017, 03:40:57 pm1. You might want to work on making your subject more meaningful, like "looking for Tektronix 152-0107-00 cross reference"2. The answer can be found in the "Tektronix Common Design Parts Catalog". One place to find it is here:https://archive.org/stream/tektronix_Common_Design_Parts_Catalog_Semiconductors3. If you search for 152-0107-00, you will find it's a 1N647, 400V 400mA diode.

author: whitevamp
author_rank: Regular Contributor
timestamp: May 16, 2017, 05:29:50 pm
content: thank you, and yes i will do that the next time.
Diode Excessive reverse leakage current - Causes? - Page 1
Forum section: electronics / projects

author: Jester
author_rank: Frequent Contributor
timestamp: April 20, 2020, 05:01:23 pm
content: I was troubleshooting a circuit today and tracked it down to excessive reverse leakage current (1n4005 diode). Checked fine with diode function on DMM, however I suspected it was flaky and found reverse leakage to be about 10uA @ 10V and 30uA@100V at room temperature.These are probably about 30+ years old. However the device looks like new inside, must have been kept in a clean lab.Does anyone know the contributing factors that cause this? Age, transients, humidity?

author: David Hess
author_rank: Super Contributor
timestamp: April 20, 2020, 07:54:00 pm
content: It could be all of those things or more likely a defective batch of diodes.

author: trobbins
author_rank: Frequent Contributor
timestamp: April 21, 2020, 12:14:37 am
content: Was the part subject to transient risk (eg. mains supply rectifier)?

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: April 22, 2020, 01:46:26 am
content: For plastic encapsulated diodes, moisture absorbtion would be a major cause for excessive reverse current by leakage, that means going around the semiconductor crystal, rather than through it.

author: graybeard
author_rank: Frequent Contributor
timestamp: April 22, 2020, 03:14:14 am
content: Moisture is a real possibility.You can try to bake it out. Set your oven for 300F or 150C and put it in overnight. Then if you measure it again and the leakage has dropped you will know it was moisture.
SOLVED-Diode identification - Page 1
Forum section: electronics / projects

author: trevwhite
author_rank: Frequent Contributor
timestamp: July 05, 2016, 12:57:33 pm
content: HiI have an unknown smt diode with markings on the body like this.EDL5RYAnyone know what it is or how I can find out? I have googled around and looked at a few databases but nothing doing.EDIT: If anyone is interested it appears to be a Fagor Electronica part. I have never heard of this company before..Trev

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: July 05, 2016, 08:15:34 pm
content: From the official page of Fagor Electronica it seems that the only kind of diode they produce is zenerhttp://www.fagorelectronica.es/en/semiconductors/catalog-diodes/diodesI also found this guide on SMD zener Diodeshttp://caxapa.ru/thumbs/588912/smd-codes.pdfAnd the only thing i could find from Fagor Electronica was this guidehttp://www.fagorelectronica.es/images/download/semiconductor/Fagor-Diodes-Bridges-Shortform.pdfHope it helps ^_^

author: Back2Volts
author_rank: Unknown
timestamp: July 06, 2016, 01:59:00 am
content: From the official page of Fagor Electronica it seems that the only kind of diode they produce is zenerNot truehttp://www.fagorelectronica.es/images/download/semiconductor/Fagor-Diodes-Bridges-Shortform.pdfGENERAL PURPOSE RECTIFIERSSCHOTTKYVERY SOFT ULTRAFASTHGIH AVALANCHE ULTRAFASTFAST RECOVERYULTRAFASTZENERTVSBRIDGE RECTIFIERS

author: trevwhite
author_rank: Frequent Contributor
timestamp: July 06, 2016, 02:28:26 pm
content: Thanks I did not expect any reponses so appreciate the effort. I think the diode identification is correct but I am not 100%
Diode Identification - Page 1
Forum section: electronics / projects

author: Rofflesaur
author_rank: Contributor
timestamp: April 10, 2017, 08:33:00 am
content: I need help identifying this zener? diode. There's no numbers or markings on it other than the green band. It's part of a module that's to be installed in a vehicle. I've been repairing a bunch of these modules, and one is missing the diode (broken off). I'm not sure what to replace it with. The trace on the PCB goes from the voltage input pin, to this diode, and then from the diode to a L487 linear voltage regulator. Green band (cathode?) is on the regulator side. Being installed in a vehicle, the voltage input can vary anywhere from 10VDC to 16VDC. With the power supply set at 13.7VDC, I show 13.757VDC at the diode anode. 12.923VDC was measured at the cathode. The L487 regulator then takes that 12.923VDC down to 5VDC to power the microprocessor and other components. Hoping someone can tell me what diode this is, so I can order one and a few spares from Mouser later. Thanks in advance. -Chris

author: Pjoudislav
author_rank: Newbie
timestamp: April 10, 2017, 09:29:32 am
content: It is most likely just a reverse polarity protection, you can use any silicon diode in MELF package. Like 78-LS4148Odesláno z mého Nexus 5X pomocí Tapatalk

author: Wimberleytech
author_rank: Super Contributor
timestamp: April 10, 2017, 04:46:36 pm
content: Here is my best guess:http://www.ebay.com/itm/50Pcs-ZMM5V1-5-1V-5mA-1-2W-Glass-Sealed-Case-SMD-Surface-Mount-Zener-Diodes-/321482243371?hash=item4ad9d5bd2b:g:~kcAAOSw32lYt-dB

author: Rofflesaur
author_rank: Contributor
timestamp: February 26, 2018, 06:54:26 pm
content: Had to revisit this question, as I've run out of parts boards. I ordered the 78-LS4148 as suggested by someone, but they turned out to be too small. Learned all about MELF packages now. I found out mine is a DO-213AB MELF (not Micro, Mini, Quadro, etc).Will this work for my application?https://www.digikey.com/product-detail/en/vishay-semiconductor-diodes-division/BYM11-1000-E3-96/BYM11-1000-E3-96GICT-ND/3025854If this really is just being used for circuit protection, I assume most of the specs are irrelevant, and the 1000V max DC reverse rating is more than enough, and likely just overkill? Is there any downsite to having a diode rated for substantially more voltage than what it will actually see?Also, here's a really crappy diagram I just made:
Diode issues? - Page 1
Forum section: electronics / projects

author: thekidinbuff
author_rank: Newbie
timestamp: December 15, 2013, 10:40:14 pm
content: Hello, to make this short, i had remote start for my car till one day when i shut off the car and it shorted out i guess and all it wants to do now is when its hooked up is turn my starter over.. Ive gone through just about everything and there are two diodes, one a zener and one a 1n4007 diode. Before i un-sodered the 4007, i diode tested it and it had .162 both ways and 0 resistance both ways. Thought that was my problem so i took it off and now it shows OL for reverse bias, which is good. I put a new 4007 in its place anyway, and now it shows exactly what the old one showed.. Im so lost. Are they good then? They do it without the main chip in too.. Only tries to start the car when i hook the 12V to the remote start module pin.Anything is greatly appreciatedThank youTheKidInBuff

author: popamp
author_rank: Newbie
timestamp: December 16, 2013, 12:31:49 am
content: it's not unusual for something to measure differently when it is in the circuit compared with when it is not in the circuit... if the diode performed as expected when isolated from the circuit then it is probably OK.

author: Rerouter
author_rank: Super Contributor
timestamp: December 16, 2013, 02:35:36 am
content: equally as you see a short, i would be very suspicious of the zener, while i havent seen enough to call it a failure mode, i have seen a considerable amount of shorted out zener diodes,

author: thekidinbuff
author_rank: Newbie
timestamp: December 16, 2013, 03:07:10 am
content: I have not removed the zener diode yet cuz its really tiny lol. and when i removed the other diode and it was fine, i thought maybe it was in the board or something. i guess i just have to remove it and see. Its not near the other diode so. The remote start is a Scytek G40RS btw.- UPDATE: now it seems to be that the zener diode is normal..

author: w2aew
author_rank: Super Contributor
timestamp: December 16, 2013, 03:22:53 am
content: I'm not familiar with your remote starter, but I'll take a shot on the dark here... The 1N4007 diode could be being used as a protection diode in parallel with a relay coil, which is why it read low-Z when in circuit. (the remote starters often use relays to take the place of the starter switch). It is possible that the relay is bad. A common failure mode is relay contacts 'welding' themselves together due to the arcing that often happens during the switching.

author: thekidinbuff
author_rank: Newbie
timestamp: December 17, 2013, 05:27:16 am
content: I originally thought it was a relay but i wasnt completely sure.. and decided to look elsewhere. Here are some pictures of the board. Any questions, just ask.In the 3rd picture... what is circled in green is the bigger relay and the 4 pins that are circled, all have continuity to each other. There are noo numbers on that relay either.
Diode manufacturer logo identification help please - Page 1
Forum section: electronics / projects

author: MichalZ
author_rank: Contributor
timestamp: October 09, 2019, 04:55:49 pm
content: Anyone know who made this? Don't recognise the logo.

author: amyk
author_rank: Super Contributor
timestamp: October 10, 2019, 01:47:08 am
content: Sescosem, now ST.Related publication from them:https://archive.org/download/ThePowerTransistorInItsEnvironment/ThompsonCsf-ThePowerTransistor.pdf

author: MichalZ
author_rank: Contributor
timestamp: October 10, 2019, 04:11:06 pm
content: Thank You very much
Diode marked "D2S21"? - Page 1
Forum section: electronics / projects

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: August 29, 2022, 06:58:41 pm
content: I have some THD silicon diodes marked "D2S21" the 21 is written in a smaller font and the 1 has a small dash under it.I can't find any info on this diode, maybe it uses some uncommon model number scheme?I also have some small THD diodes marked "0440" the first "04" is written horizontally (the pins would go vertical when reading it) but the other "40" is written vertically, 4 being above and 0 bellow.
Diode output opto couplers - Page 1
Forum section: electronics / projects

author: 741
author_rank: Frequent Contributor
timestamp: October 01, 2021, 11:45:24 am
content: I'd like to source a diode output optocoupler for simulating a discrete IR Led/ IR PIN diode smoke chamberThe output should be a normal IR photodiode. However I can only find gate drivers (like TLP3906) when I search for diode output ('linear output'?) types. Should I simply look for 3-pin (i.e. including base) transistor output couplers?If yes, what are the reasons to choose base-collector (B-C) vs. base-emitter (B-E) diodes - and what is best done with the spare lead? That is, to best replicate a discrete photodiode.Also, what are nice actual part numbers for this application? The input is about 100mA for 100uS. I'm currently perusing this link (https://tinyurl.com/77zcm5w7)I might be able to divert some of the input current if needs be. (In fact, that would be very useful to simulate different smoke levels).

author: StillTrying
author_rank: Super Contributor
timestamp: October 01, 2021, 01:14:38 pm
content: HCNR201IL300It might be quicker to make one.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 01, 2021, 01:36:17 pm
content: When using a phototransistor as a photodiode, that is with no added gain, one can use either the collector, the emitter or both leads connected. This difference shoudl not be large. The unused terminal would be left open.Compared to a real photodiode the leakage current may be a bit on the high side and the B-E diode only works for low voltage (e.g. like 5 V max). This is at least the case with normal transistors and I would expect the phototransistors to behave similar. Chances are the coupling is relatively large compared to the smoke detector case. So a low CTR may be OK.

author: 741
author_rank: Frequent Contributor
timestamp: October 01, 2021, 02:00:27 pm
content: I recall seeing someone stating a transistor B-C diode (for an ordinary, 'non-opto' transistor) was more like an ideal diode. I've not found a good exposition / comparison though.

author: 741
author_rank: Frequent Contributor
timestamp: October 01, 2021, 02:11:03 pm
content: I've just now connected an SFH203 IR diode directly to a voltmeter.The polarity of the "photovoltaic mode" output is+ve = long lead (ANODE, A)-ve = short lead: flat face on dome also, (cathode, K)So it seems that (in 'solar cell mode') the P.D. is such that Anode is +ve. Therefore (I suppose..) the photocurrent is moving in reverse (from K ----> A).I had to try it out because I was left unsure about this basic fact after some research...

author: StillTrying
author_rank: Super Contributor
timestamp: October 01, 2021, 02:22:07 pm
content: Two of us tried using just the B-C junction of optos here:https://www.eevblog.com/forum/beginners/floating-probe!-for-$2-50/msg1819946/#msg1819946We were after more speed but didn't get any.

author: Kleinstein
author_rank: Super Contributor
timestamp: October 01, 2021, 02:46:30 pm
content: For higher speed a photodiode should be used with a bias voltage in reverse. This can reduce the capacitance and thus increase the speed.
Diode Selection - Page 1
Forum section: electronics / projects

author: jwhitmore
author_rank: Regular Contributor
timestamp: January 22, 2016, 04:57:54 pm
content: I've got a power supply based on an LT3603. That chip can supply 2.5A so I've got an input protection diode and an output protection Diode. I assume that both of these D4 and D6 should be schottky 3A forward current and 20V reverse voltage diodes. However D3 in the circuit I've no idea about and the data sheet for LT3603 don't mention anything specific, well if it does I missed it.On the USB side it's a bit complicated (for me anyhow) as the device can be in USB Host mode, supplying 5V to the USB Bus and in USB Device mode where it's either self powered or powered by the USB Bus, hence the P Channel and all that guff. I'm not sure what way I'd select D1 and D2. I must actually recheck the data sheet for that TPD3S0X4 (http://ie.farnell.com/texas-instruments/tpd3s014dbvr/current-limit-switch-usb-port/dp/2472981) To see if that's even required.Anyhow in the case of Diode selection how do you estimate the currents involved?

author: moffy
author_rank: Super Contributor
timestamp: January 22, 2016, 10:40:38 pm
content: D1 is only low current to provide a boost voltage to turn on the N channel MOSFET, it could be a 1N914 etc. Also D2 could be the same as it looks like it is only used for startup.

author: jwhitmore
author_rank: Regular Contributor
timestamp: January 31, 2016, 12:19:42 pm
content: Thanks for that, I'll add some 1N914 to my parts bin. I guess you really have to understand a circuit to judge what current to expect and as a SW head a full read of the art of electronics is just not going to happen ;-)
Diode temperature sensor calibration using Arduino and SHT15 module - Page 1
Forum section: electronics / projects

author: prenato
author_rank: Regular Contributor
timestamp: December 23, 2013, 07:56:52 pm
content: Here's a technique that might be useful in some projects:http://paulorenato.com/joomla/index.php?option=com_content&view=article&id=128:diode-temperature-sensor-calibration-using-arduino-and-sht15-module&catid=4:projects&Itemid=4Paulo
Diode to prevent current backfeed? - Page 1
Forum section: electronics / projects

author: DW1961
author_rank: Frequent Contributor
timestamp: December 03, 2020, 06:08:36 pm
content: I recently ran into a problem where a computer 5V LED hub connected to the PSU's SATA connection was feeding the PSU's standby voltage back into the motherboard's DLED riser and then out of the 24pin power connector back into the power supply. That was allowing the PSU's fan or other connected case fans to spin very slowly, due to low voltage. It wasn't a good situation.I found out that this behavior is due to how the motherboard is designed. Other boards don't do it.Anyway, since I found where the power was coming from, and DLED has 3 pins, one for Power, Ground and the Digital information, what I did was just to cut the power lead coming from the motherboard's header that plugged into the DLED hub that is powered by the SATA connection. That worked well, since I don't need the MB's power going to the hub, as it is plugged into the SATA power port. That, and I can still use the MB's 2A DLED power by using a splitter cable.However, as I learn more about electronics, I was sitting here to day thinking that I could have just used an inline 2A diode on the MB side inline with the 5+ wire to prevent that feedback coming from the HUB which is powered by the SATA connection. This assumes that the power is coming from the SATA side, back into the motherboard, and then feeding back into the PSU power cables.Am I correct?

author: bob91343
author_rank: Super Contributor
timestamp: December 03, 2020, 06:33:12 pm
content: I think so.

author: james_s
author_rank: Super Contributor
timestamp: December 03, 2020, 07:41:38 pm
content: Just keep in mind the forward voltage drop of a diode. Since there is not much headroom starting out with 5V you should probably use a Schottky diode.

author: Zero999
author_rank: Super Contributor
timestamp: December 03, 2020, 10:25:02 pm
content: Or use a MOSFET and ideal diode controller IC.https://www.ti.com/lit/ds/symlink/lm74700-q1.pdfhttps://datasheets.maximintegrated.com/en/ds/MAX40203.pdfhttps://www.analog.com/media/en/technical-documentation/data-sheets/ltc4359.pdf

author: DW1961
author_rank: Frequent Contributor
timestamp: December 04, 2020, 01:22:48 am
content: Quote from: james_s on December 03, 2020, 07:41:38 pmJust read up on those. That sounds like a perfect fit. Thanks for pointing out diode V drop.In application, for my needs, LOL, cutting the power wire was probably the thing to do.