hybridfree/eevblog-posts huggingface dataset:
Can you hack a CdS light sensor to include an FET ? - Page 1
Forum section: electronics / projects

author: RJSV
author_rank: Super Contributor
timestamp: July 08, 2020, 08:54:54 am
content: A long time pet project involves human retina simulation (in hardware). An adjunct question:. Cansomebody point me to some really good reviews ofretina functions, from an engineering perspective ? I'mthinking a textbook having such sub-systems like adaptation to ambient light levels, low and high.So, my hypothetical CdS 'array' would have a cadmium chip 'die' that includes depositing sulfates, inthe currently used manufacture process, plus extra 'stuff' deposited on the cadmium substrate, for functional integrated FET.Then, the suggested machine vision chip will need some copper deposits for interconnections throughout an array. Maybe first exp build would be anoptical 25 by 25 array. I'm maybe sending an existing gap between 3-D printers, and traditional vapor deposition techniques. Are there near-atomic sized3-D printers out there ?My micro-array would include analog signal capableconnections to neighboring cells. So a small pulsecould propagate to each adjacent cell, to the left neighbor, right side neighbor, and above and below.A small pulse originating from incoming light wouldthen 'leak' from a single 'pixel' and propagate in everydirection, encountering each next CdS based cell. Youwill need closely controlled gain/attenuation across this 25 X 25 cell array.OK then that's my set of problems. NOW, what researcher can teach me about the human retina ? Isit a pulsed analog, pure analog, or partial processinglayer, to then migrate neurons out into the brain, wholesale for further processing. That would include edge detection, motion sensitivity, and all the other processes that operate way way beyond a single neuron responding to light.I'm willing to put the time and effort to study socome on: Any researchers out there rise to the challenge. I just maybe can't afford a $400 textbookon characterising vision systems front ends.Thanks for attention. RJ
Can you have multiple signals on a common mode choke core? - Page 1
Forum section: electronics / projects

author: caffeinatedbard
author_rank: Regular Contributor
timestamp: December 10, 2013, 03:07:26 pm
content: So this question is pretty simple.With a common mode choke, can you have multiple signals "sharing" the same core without interference?For example, two low voltage data/signal lines wound around the same core.-bard

author: calexanian
author_rank: Super Contributor
timestamp: December 10, 2013, 10:57:47 pm
content: No. It will induce from one coil to another. Just like a transformer.
Can you help me find a Rotary Potentiometer with a switch? - Page 1
Forum section: electronics / projects

author: RossK
author_rank: Contributor
timestamp: September 11, 2013, 05:13:23 pm
content: I expected to be able to find pot's with rotational switches built in... but i just don't see them in the form factor or price point i expectIdeally i would like to find one with a form factor similar to the one pictured herehttp://www.digikey.com/product-detail/en/EVU-F2LFL3B53/P3K1502-ND/243636vertical (top) adjustResistance in the 10k-100k rangesingle rotationwith a rotary switch or a single detent at <= 10% (thinking outside the box i could actually do without the switch given a well placed detent)and ideally in the under $2 price point but absolutely under $5Has anyone seen such a thing?Thanks for your eyes!
Can you help me find this connector? (Zenza Bronica flash cable) - Page 1
Forum section: electronics / projects

author: adrifromhh
author_rank: Contributor
timestamp: November 01, 2020, 10:41:34 am
content: This is the Flash Connector for an analog Zenza Bronica ETRSi medium format camera.(Bronica ETR SCA Adapter 386 for use with Metz SCA flashes)I can't imagine Bronica developed this connector themselves. Does anyone have an idea from which manufacturer this might be and if it's still available?I don't really have any information about it. It looks like it has some lock-action.

author: adrifromhh
author_rank: Contributor
timestamp: November 01, 2020, 10:53:07 am
content: It looks like Nikon used the same type of connector, only with a higher pin-count.https://www.nikon.de/de_DE/product/accessories/speedlight/cords/ttl-cord-sc-24
Can you help me identify the possible function of this hardware - Page 1
Forum section: electronics / projects

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 18, 2018, 02:30:17 am
content: My brother got a piece of electronics from his work, he doesn't know what it is or what it's from. It was heading for the recycling bin.It looks early to mid 1970s vintage, something industrial or at least non-consumer, for sure RF related.There are two large connectors that look like robust F-type connectors, with a bias-tee on one connector.That signal goes through a cap to something I consider lowish RF looking, ie FM to 2m band.From the same connector pin, an inductor goes to two diodes, and from the looks of the capacitors and transistors, create +/- DC supplies to feed a handful of transistors. Looks like a few stages of gain, and signal goes out the other connector.RF + AC power on a cable? Judging by the value of the capacitors, it could be 400Hz, like in aircraft?It's built on 1mm thick steel, hand-built, looks quality. I'm too lazy (read: tired and sick) to figure it out.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 18, 2018, 02:57:39 am
content: Oops, I guess I meant "where this possibly comes from or what it was used in", the function seems pretty clear: it's gain. There is a DPDT switch that switches a filter in and out from the input too.

author: BrianHG
author_rank: Super Contributor
timestamp: April 18, 2018, 04:26:21 am
content: Maybe an RF amp, or transmitter amp.
Can you ID these TO-247-like MOSFETS? Mark: HC1214D  49956SOCN G770636-3  1206.. - Page 1
Forum section: electronics / projects

author: evb149
author_rank: Regular Contributor
timestamp: September 15, 2014, 06:16:00 am
content: Hi all,Can anyone who can easily ID these TO-247-like MOSFETS (I think that's what they are) please share the data / citation?Marking example:HC1214D49956SOCNG770636-3 1206527050The logo looks like MicroSemi to me, but I have found nothing in their catalog, PCNs, packaging specifications, part lookup to confirm that this is or ever was one of their part numbers. The marking does not seem to even fit into what seems to now be their standard product family / parametric designation scheme so it doesn't even seem similar to any numbering schemes they now use to me.I suppose it could be an old part number from before some past change in their device naming or line-up, but, if so, I have found no references to the parametrics or data to support that.A data sheet link would be ideal, but even basic summary parametrics of voltage / current ratings would be useful.Thanks for looking in case this is familiar to you!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 15, 2014, 07:56:35 am
content: House marked?I take it from the picture, you have a bunch of them surplus? Probably easier to test than to find data.Tim

author: evb149
author_rank: Regular Contributor
timestamp: September 15, 2014, 03:46:37 pm
content: Thanks for the response, yes, perhaps it is a customer specific marking scheme. I have a small few I thought I'd identify or test and see if the part would be a useful jellybean or for some particular projects as opposed to a set of distributor sourced ones.I'd have just checked the drain source breakdown, gate threshold, and on resistance if I had a curve tracer handy, though the measured breakdown voltage could be quite a bit above the rated value. The on resistance and package type's general characteristics would give some indication of the probable maximum DC and medium pulse width current handling capability.I should be able to measure the gate capacitance and on channel resistance anyway easily enough at Vgs 10V-15V or so.
Can you identify these old (late 70s / mid 80s) chips?  - Page 1
Forum section: electronics / projects

author: SaabFAN
author_rank: Frequent Contributor
timestamp: May 15, 2016, 10:25:53 am
content: I just got a bunch of chips that came with a 8279 Display-/Keyboard-Controller I needed for a repair.Aside from a few 2k and 64k SRAMs, there also were several other chips, of which I've been unable to identify a few. I hope you can help:- 33512DC = 9bit FIFO ?- 809 v L6621 / 7219-0629 / 211003-02 =<- Haven't been able to find anything with any of these numbers. Custom-Chip maybe?- D855D =- SAB1792 =- µPD757C = 4bit Microcontroller?

author: bktemp
author_rank: Super Contributor
timestamp: May 15, 2016, 10:33:05 am
content: Quote from: SaabFAN on May 15, 2016, 10:25:53 amIf google finds nothing at all, the numbers are most likely wrong:D855D -> U855D (Z80 PIO)SAB1792 -> SAB1797-02P (Floppy Disk Controller)

author: amyk
author_rank: Super Contributor
timestamp: May 15, 2016, 03:21:39 pm
content: 3351-2 datasheet is in here:http://bitsavers.trailing-edge.com/pdf/fairchild/_dataBooks/1975_Fairchild_MOS_CCD_Data_Book.pdfSAB1797 is a FDC:http://www.datasheetspdf.com/PDF/SAB1797/554206/17219-0629 is a VLSI Technology ASIC, can't seem to find anything else on it eitherµPD757C is a mask ROM microcontroller of some sort, probably custom for some other company because I can't find anything else on it.

author: ChristofferB
author_rank: Frequent Contributor
timestamp: May 15, 2016, 04:06:32 pm
content: U880 by "FWE" is a DDR z80 clone, so 855 is very likely a z80 family chip. +1

author: SeanB
author_rank: Super Contributor
timestamp: May 15, 2016, 04:31:56 pm
content: NEC did a lot of mask ROM microprocessors, mostly a Z80 and some built in peripherals, like the UART, RIOT and PIA along with some RAm as well. They generally were custom made for customers like calculator and copier manufacturers, and a lot were used in dot matrix and old thermal printers.Going to guess the 855 is a cloned 8255 PIA chip.
Can you identify these SMD parts? - Page 1
Forum section: electronics / projects

author: zaoka
author_rank: Frequent Contributor
timestamp: December 21, 2013, 06:32:51 pm
content: Its used to drive IGBT on Panasonic Plasma TV, sustain board.

author: free_electron
author_rank: Super Contributor
timestamp: December 22, 2013, 12:03:33 am
content: judging by the font these are either Sanyo or Rohm parts ... it's gonna be hard...

author: Niklas
author_rank: Frequent Contributor
timestamp: December 22, 2013, 12:27:05 pm
content: A candidate for the SOT23 package:http://www.onsemi.com/pub_link/Collateral/CPH5524-D.PDFIn stock as single units at Mouser, no stock at Digikey

author: SeanB
author_rank: Super Contributor
timestamp: December 22, 2013, 12:33:45 pm
content: Looks about right as a buffer, the other must be a high side driver for the FET the buffer is driving.

author: amyk
author_rank: Super Contributor
timestamp: December 22, 2013, 12:55:21 pm
content: Quote from: free_electron on December 22, 2013, 12:03:33 amThanks for the hint... 2nd one is a BD8693according to thisandthis. Oddly enough, no other mentions of it on Rohm's own site, but plenty of Chinese sites selling them. The picture here is pretty conclusive:http://hlxdianzi.ic37.com/ProductView.asp?Productid=569751

author: nukie
author_rank: Frequent Contributor
timestamp: December 23, 2013, 08:34:37 pm
content: Check for shorted blue Monolithics, I just fixed another one yesterday. They are hard to spot but the fading color should help. Use an IR thermometer don't use your fingers. Fets driver die is possible but the monolithics short should be ruled out first.

author: zaoka
author_rank: Frequent Contributor
timestamp: December 23, 2013, 10:40:42 pm
content: Quote from: nukie on December 23, 2013, 08:34:37 pmWhat do you mean by monolithics? (blue capacitors?)Any replacement for this transistor?

author: nukie
author_rank: Frequent Contributor
timestamp: December 24, 2013, 04:04:36 am
content: Yes the caps. What issues are you having?

author: zaoka
author_rank: Frequent Contributor
timestamp: December 24, 2013, 02:13:16 pm
content: 5-6 IGBT's shorted...
Can you identify this German relay manufacturer? - Page 1
Forum section: electronics / projects

author: LaserEng
author_rank: Regular Contributor
timestamp: July 09, 2019, 01:52:02 am
content: Anyone now what brand the relay in the attachment is?I have not seen this M in a box logo before and haven't been able to identify from Google, the relay part number S3-L-6V only shows up SDS Relais and Panasonic as manufacturers but neither use this M logo. SDS Relais where a German company which I think became NAIS and then Panasonic but don't know if there was another owner between these companies

author: LaserEng
author_rank: Regular Contributor
timestamp: July 09, 2019, 02:05:29 am
content: Thanks, surprised Panasonic use that M logo as normally they print Panasonic on their parts, guess it must be from the parent company, Matsushita.
Can you identify this oscillator? - Page 1
Forum section: electronics / projects

author: KrudyZ
author_rank: Frequent Contributor
timestamp: May 30, 2024, 02:36:34 am
content: It's in a 2.5 mm * 2 mm SMD package with four pins.There are two lines of text on the lid:RK33.3T.18BE1VI know it's a 33.3 MHz oscillator, but would like to know the manufacturer and accuracy spec.I came up empty with my searches.

author: Terry Bites
author_rank: Super Contributor
timestamp: May 31, 2024, 04:24:39 pm
content: Rockchip?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 31, 2024, 10:52:21 pm
content: You can do a search for"2520 crystal"It's a fairly common sized package for crystals and it's made by a bunch of different manufacturers.This package is used both for passive crystals, oscillators, TCXO and possibly more variants.

author: KrudyZ
author_rank: Frequent Contributor
timestamp: June 04, 2024, 04:01:05 am
content: Quote from: Terry Bites on May 31, 2024, 04:24:39 pmRockchip does use RK as part of their product names, but I don't think they make oscillators...

author: KrudyZ
author_rank: Frequent Contributor
timestamp: June 04, 2024, 04:04:28 am
content: Quote from: Doctorandus_P on May 31, 2024, 10:52:21 pmI tried that, but couldn't find anything with the RK marking.I'm interested in the specs for this specific part, in particular accuracy over temperature range.It is used on an AMD / Xilinx K26 SOM and for whatever reason, they do not publish this piece of information.
Can you identify this SMD-Component? - Page 1
Forum section: electronics / projects

author: SaabFAN
author_rank: Frequent Contributor
timestamp: December 04, 2016, 03:26:39 am
content: Some time ago I bought some components that I labeled BAT60J in my parts-box, which they are clearly not.I don't know exactly where I got those, but my Digikey Orders contain no parts that look like them.It is a Tiny 4 Pad SMD-Package with a silver metal top and the following markings: I600T (could also be 1600T) E4Y19Do you have any idea what part this is? Google Searches for I600T and E4Y19 came up empty so far.

author: chicken
author_rank: Frequent Contributor
timestamp: December 04, 2016, 03:54:18 am
content: 16MHz crystal would be my guess.

author: android
author_rank: Regular Contributor
timestamp: December 04, 2016, 03:57:30 am
content: Possibly Epson:http://www.epson-electronics.de/electronics/cms/index/495

author: SaabFAN
author_rank: Frequent Contributor
timestamp: December 04, 2016, 11:08:05 am
content: Crystal sounds plausible.I'll try to check it with my little home-made Network Analyzer.If I remember corectly, I wanted to buy Pin-Diode arrays or fast switching diodes, but received these components instead. Wondering about the strange package, i just labeled the box to what was on the envelope (ebay order) and put the components in there without giving it much thought

author: wraper
author_rank: Unknown
timestamp: December 04, 2016, 11:15:30 am
content: Either quartz crystal or oscillator, most likely to be crystal. Crystal should have two GND pads on the opposite corners connected together and to the metal cap on the top. Oscillator likely will have only one GND pad.

author: SaabFAN
author_rank: Frequent Contributor
timestamp: December 04, 2016, 12:57:39 pm
content: I just measured the components and got a rather interesting result:I got a flat line when I swept them with my Network Analyzer (10kHz to 50MHz DDS-Based Scalar Network Analyzer with an Arduino as interface and controller:http://rheslip.blogspot.de/2015/08/the-simple-scalar-network-analyser.html) from 1MHz to 50MHz.Then I had the idea of using my new R3131A Spectrum Analyzer and a noise source to see what the frequency response is up to 3GHz.This is the result:1.6GHz Notch-Filters. Or I connected something wrong/measured wrong and they are 1.6GHz SAW Bandpass Filters
Can you imagine from a picture what this item is used for? My engineer told me i - Page 1
Forum section: electronics / projects

author: Nigen
author_rank: Newbie
timestamp: March 05, 2024, 02:43:12 am
content: Can you imagine from a picture what this item is used for?My engineer told me it might be used for lighting.Others say it may be used for connectors.

author: Circlotron
author_rank: Super Contributor
timestamp: March 05, 2024, 06:17:13 am
content: We once used a 96(?) way connector with split bowed pins that could be pressed into a pcb backplane without the need for soldering. Looked similar to that.

author: HalFoster
author_rank: Frequent Contributor
timestamp: March 06, 2024, 10:52:28 am
content: Looks like a low-res drawing of a standard 176 pin backplane connector.

author: youngda9
author_rank: Regular Contributor
timestamp: March 06, 2024, 03:42:45 pm
content: Looks like an airplane seating chart...people packed in like sardines.
Can you put diodes in parallel if they are in the same IC? - Page 1
Forum section: electronics / projects

author: Dmeads
author_rank: Regular Contributor
timestamp: November 20, 2019, 04:13:48 am
content: okay, I know you cant really put diodes in parallel becuase it really doesnt split current equally, but if the diodes are in the same IC, (on the same silicon die), could you then put them in parallel because they are better matched in terms of parameters?I am thinking of doing it with this componenthttps://www.st.com/resource/en/datasheet/stps60sm200c.pdfthe pinout/shchematic are on the first page of the link above.Thanks.

author: Hiemal
author_rank: Regular Contributor
timestamp: November 20, 2019, 05:00:18 am
content: It's common practice to do that actually. If you check most AC-DC or even DC-DC converters they'll have a schottky rectifier on the output with both diodes tied together in parallel just like you're suggesting.Since they're in the same package they also share the same rough temperature, so i can't see why it would be problematic.

author: David Hess
author_rank: Super Contributor
timestamp: November 23, 2019, 01:49:46 pm
content: Integrated diodes are not only well matched but also very well thermally coupled so they work fine in parallel. If you were to take discrete diodes, match them, and thermally couple them, then they would also work well in parallel although not as well as integrated diodes.For a dual power diode of uncertain construction and matching, I would not assume that placing both diodes in parallel doubles the current rating. I might derate the parallel current rating to 75% in the worst case but in a good design, this would already be accounted for with the general derating.In a production design, I would do some testing to find out how well the dual diodes are matched and thermally coupled if I was operating at close to their maximum limits. Unfortunately manufacturers do not specify or discuss this that I have seen.

author: SeanB
author_rank: Super Contributor
timestamp: November 23, 2019, 03:56:38 pm
content: Those diodes are not on the same piece od silicon, but generally do come from the same die, and are relatively close to each other during manufacture, so are going to be reasonably well matched. However I would, as said above, derate them for parallel operation, and would rather regard parallel operation as a way to drop forward slope resistance and thus forward voltage drop under load, and run the pair at the same forward current as a single diode inside. Makes them easier to heatsink, as you have a lower heat dissipation from them. Drops the power dissipation from around 20W to around 12W using the 2 in parallel, making your thermal design easier. If you do need 60A choose a different dual diode rated for 60A per section instead, though you might be able to get away using 2 of the packages in parallel, making sure to match the trace lengths of the PCB to get the diodes to share current, using the PCB resistance as a rather poor but free ballast resistor.
Can you put peltier elements in series? - Page 1
Forum section: electronics / projects

author: BreakingOhmsLaw
author_rank: Frequent Contributor
timestamp: January 24, 2022, 11:10:51 am
content: Can you put Peltier elements in series? Do they behave like a resistive load? Or will they change with temperature? I'd do a measurement, but they haven't arrived yet.Background: I'm building a cloud chamber for my kids school that has nine Peltier elements. In order to reduce the required cable gauge, I am considering to put three in series and run them from a 36V / 35A supply. Otherwise I'd need to supply 12V 100Amps, yikes!

author: Ian.M
author_rank: Super Contributor
timestamp: January 24, 2022, 11:23:55 am
content: Seeing as the modules themselves contain series chains of Peltier junctions, putting reasonably matched modules in series is permissible. They do *NOT* behave like a resistive load, a more accurate 'rule of thumb' model; would be a resistor in series with an opposing voltage source proportional to the temperature differential.

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 24, 2022, 12:51:38 pm
content: Quote from: BreakingOhmsLaw on January 24, 2022, 11:10:51 amThat's cheaper than you think, a surplus server PSU or two will do the trick. A 36V PSU would be a lot less common.

author: tszaboo
author_rank: Super Contributor
timestamp: January 24, 2022, 12:55:51 pm
content: Quote from: Ian.M on January 24, 2022, 11:23:55 amExactly. I would say, from if it comes from the same series, that's going to be fine, if they are on the same heatsink and thermally coupled.They are not resistive, they are an active element, PN junction. Quite non-linear, and the non linearity matters on the temperature. But unlike MOSFTES, where if you do this, the one with weakest cooling will eventually blow up due to thermal runaway, as I remember TEC coolers will actually stabilize instead of thermal runaway. Can someone please confirm this?
Can you recommend PMIC with charger (can be from chinese manufacturer) - Page 1
Forum section: electronics / projects

author: c64
author_rank: Frequent Contributor
timestamp: November 05, 2021, 01:58:06 am
content: Requirements are:at least 3 buck convertersone buck converter must be able to produce at least 1.5A @ 1.2Vcharger and gauge for single cell Li batteryOptional but nice to have:5v outputability to set voltages without programming (by using resistor dividers for example)built-in RTCsupport for power button (press to power on, long press to power off, etc.)5v as input sourceI don't mind if it's made by chinese manufacturer, but it must be available so sale (and not on ebay or alibaba). I found few very nice chips but only can buy them on taobao.
Can you run multiple isolated DC/DC converters in parallel for more current? - Page 1
Forum section: electronics / projects

author: ivanjh
author_rank: Unknown
timestamp: August 19, 2012, 02:23:42 am
content: I have a scenario where I need ~200mA @ 12V isolated from the main 12V supply.The B1212LS-1W is rated at 83mA -http://www.mornsun-power.com/UploadFiles/pdf/A_S-1W%20&%20B_LS-1W_EN.pdfThey're an unregulated unit.Would there be any problem with getting 3 and wiring them up in parallel?

author: Psi
author_rank: Super Contributor
timestamp: August 19, 2012, 03:06:13 am
content: Should be fine, but i would put a low value resistor in series with each.It's not really needed but i would do it anyway.

author: ivanjh
author_rank: Unknown
timestamp: August 19, 2012, 08:29:12 am
content: Quote from: Psi on August 19, 2012, 03:06:13 amIs that to provide a minimal required load?

author: Psi
author_rank: Super Contributor
timestamp: August 19, 2012, 10:26:37 am
content: na, i mean in series to the higher current VCC pointunit1 +out ---res ---|unit2 +out ---res ---|------ output +unit3 +out ---res ---|unit1-3 -out --------------- output -It's just to provide a little give and take for the slightly different voltages out of each unit.It can also help to stop a bad unit from taking down the others in some situations.

author: Rerouter
author_rank: Super Contributor
timestamp: August 19, 2012, 10:42:31 am
content: if there all isolated using your diodes to share the current will do the same,out of curiousity what wattage and topology are you working with,? i myself am struggling with choice on higher wattage switchmodes,

author: Psi
author_rank: Super Contributor
timestamp: August 19, 2012, 11:06:56 am
content: yeah, diodes are better if you can tolerate the voltage drop.
can you split cctv cat cable to 2 different poe ports - Page 1
Forum section: electronics / projects

author: mdronic
author_rank: Contributor
timestamp: March 08, 2016, 02:58:53 am
content: Have recently purchased a cctv nvr and cameras. I have 2 unused Poe ports. My idea was Can i split the feed , data and power so that the same camera can be plugged into 2 Poe ports at the same time. the result hopefully being 2 channels running the same image. Why you ask? I want to set up each channels with different parameters and motion areas.One idea was to use 3 lengths of cat 5e or 6 cable in a "Y" put rj45 plugs on the ends. Would the two power inputs to the camera be a problem, and the data split. The nvr is a swann nvr8 7090 with 8 separate Poe ports.Has anyone done something similar, better ideas greatly welcomed.

author: Delta
author_rank: Super Contributor
timestamp: March 08, 2016, 03:15:02 am
content: No. No you cannot.You are still thinking in terms of analogue composite video! What you want to be able to do should be achievable in software though...

author: mdronic
author_rank: Contributor
timestamp: March 08, 2016, 03:31:20 am
content: Thanks, yes still thinking analogue. The nvr is actually made by hikvision for swann I think. The functionality is slightly less and fewer features though. Each Poe port seems to be specific for that one channel. Plug and play. There doesn't appear to be anything in it's brain to allow the same image on two channels.

author: mdronic
author_rank: Contributor
timestamp: March 08, 2016, 06:22:09 am
content: Rechecked. The nvr want allow me to put the same ip camera address in for 2 channels. Canes back with that camera address already exists, have tried using the plug and play and manual. The software method seems not available for this nvr. Any suggestions?. Any way of rigging something up to put the signal to two ports and 2 channels physically.

author: Delta
author_rank: Super Contributor
timestamp: March 09, 2016, 03:25:29 am
content: Does the camera also have an analogue output?If so you could use an ethernet capture device. Or just mount another camera next to this one!

author: mdronic
author_rank: Contributor
timestamp: March 09, 2016, 08:17:49 am
content: The camera only has a ip Rj45, no analogue bnc. I know hikvision has a ? Module that you can plug analogue cameras into Nvr.... a bit on the pricey side from memory and D1 resolution from memory. And obviously not a solution for this.I am unfamiliar with Ethernet capture devices . ? How would this work?I am already running the old analogue dvr and cameras in parallel with the digital ip cameras. Turning out to be quite interesting comparing side by side. The analogue are actually better in some situations. Adding an extra 3mp camera has crossed my mind but no funds in the bank and house already looking "dodgy" with the other two. Also room difficult.
Can you trigger short exposures for TIC at points which the target is at same po - Page 1
Forum section: electronics / projects

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: June 03, 2023, 12:28:21 am
content: Is it possible to trigger short exposures on a thermal imaging camera at points when the target object is at the same position?The goal is to capture the thermal image of a fast moving object, for example a flywheel... Triggering when the wheel is in the same position as last time. So like a stroboscope but without a strobe

author: Georgy.Moshkin
author_rank: Frequent Contributor
timestamp: June 03, 2023, 03:09:59 pm
content: It may be possible. Unfortunately, many sensors may use rolling shutter and have no control registers to set required exposure time, so fast moving object will be smeared and "desynchronized". On the other hand, these sensors are usually have very low resolution, and high readout frame rates may be possible (eliminating difference with global shutter approach, you can google the difference). It is worth checking if some of Melexis MLX or similar sensors are better suited for this task. EDIT: If you find a way to trigger some thermal camera, final performance would depend on sensor used.
Can you use differential pins on an USB-C connector for serial use? - Page 1
Forum section: electronics / projects

author: joe_electric
author_rank: Newbie
timestamp: May 04, 2023, 09:59:48 pm
content: I was wondering if anyone knows whether it is compliant to use some of a USB-C connector's SBU and tx/rx pins to communicate 3.3V serial data directly, without using converters. The USB-C would also be doing power delivery. Thanks.

author: ddavidebor
author_rank: Super Contributor
timestamp: May 04, 2023, 10:03:57 pm
content: SBU maybe, tx/rx no unless you negotiate an alternate mode first using the CC lines.

author: joe_electric
author_rank: Newbie
timestamp: May 08, 2023, 09:06:28 pm
content: Thanks for the reply! Alternate mode would definitely be a viable option. Would anyone else know whether during 20V power delivery, it is compliant to send serial data over the sidebands?

author: ddavidebor
author_rank: Super Contributor
timestamp: May 09, 2023, 10:53:19 pm
content: You would need to double check, but I believe the way it's done usually is you use a multiplexer or an analog switch to keep the sidebands disconnected until you have authenticated your device.This kind of authentication can be done through USB-PD or the USB protocol in practice. I'm not sure if the standard enforces a particular mechanisms.

author: joe_electric
author_rank: Newbie
timestamp: May 10, 2023, 04:36:44 pm
content: Thank you so much for your help!

author: dmendesf
author_rank: Frequent Contributor
timestamp: May 10, 2023, 05:45:53 pm
content: Google for "Debug Accessory Mode" (DAM) and USB Cereal:https://www.cnx-software.com/2023/02/15/usb-cereal-an-open-source-hardware-usb-c-debugging-development-tool/
Can you use two IR2113 to control brushed motors? - Page 1
Forum section: electronics / projects

author: ludko_pro
author_rank: Newbie
timestamp: February 28, 2019, 09:35:37 pm
content: I know it's a bit of a stupid question but I saw thishttps://easyeda.com/GreatScott/IR2113_H_Bridge-09ef385286f74867988316035c669a17schematic used as a driver for a high frequency wireless charger. The fact that the driver is designed to be used with N channel transistors made me wonder if I could repurpose it and use it to adjust the speed of a 12 V motor with a maximum current draw of about 2A (with the help of PWM and an Arduino Uno). I've tried using the ubiquitous L289N and I think it's clear to everyone that I was experiencing huge power loss and my case calls for maximum efficiency.Unfortunately I'd never had to design motor drivers before. My first attempt was a huge flop and it only seemed to be exacerbating the power loss, this time due to the shoot through, not the ancient chip.Thus far, I've modified the schematic a bit - I've added 4 fly back diodes for the motor, I've removed the 555 Timer and I have added a SN74HC14 Schmitt Inverter to invert the input signal at one of the low side. When I tried building it yesterday nothing seemed to work, even though I tested it just by connecting LIN and HIN to 5 V or GND. The current schematic:https://imgur.com/a/97DnxW8I hope someone has any idea what to do because at this point I'm lost. Thanks for reading out!Antoan
Can't figure out voltage feedback on these 0-30V lab PSU's - Page 1
Forum section: electronics / projects

author: floobydust
author_rank: Super Contributor
timestamp: June 30, 2017, 05:44:34 pm
content: These three 0-30VDC analog bench power supplies, I can't figure out the voltage feedback.I'm expecting a voltage-follower configuration but the level-shift or typos are mixing me upThey all have op-amp power and Vref floating common to the PSU OUT(+) terminal.The BK1630:Vref pot VR102 (voltage divider Vref) to inv. input (-) LM301.PSU OUT- to voltage divider to non-inv. input (+) LM301.The BK1670, 1671:PSU OUT+ direct to inv. input (-) U1A.PSU OUT- to pot (voltage divider PSU OUT-/Vref), to non-inv. input (+) U1A.The HY3005:PSU OUT+ schematic error I think missing line/dot to inv. input (-) N1?PSU OUT- to pot (voltage divider PSU OUT-/Vref), to non-inv. input (+) N1.For a 30V output, I think the V feedback op-amp will always see 0V (to common) on (-) input and should servo to match -30V on the + input but the pots go to Vref=Vout+2.5V then I got lost. It doesn't seem like enough voltage.

author: floobydust
author_rank: Super Contributor
timestamp: June 30, 2017, 09:43:57 pm
content: It's not intuitive, I did a loop equation with KVL and Vout=(Vref(R1/(R1+R2)))/(1-(R1/(R1+R2)); LTSpice sim helped to confirm.All I was trying to figure out is if a 5k potentiometer would work with a 10V ref. but is about 1/4W dissipation, as you get 40V on the divider at max. 30V output.I'll use the junkbox 50k multi-turn I have instead.

author: Kleinstein
author_rank: Super Contributor
timestamp: July 01, 2017, 09:32:02 am
content: If we ignore the small effects of R22 and R21 (usually R22 is not there), the circuit shown below has an output voltage of V_out = V_ref * (R19 / R20).The circuit with the floating regulator can be easier understood if the positive output terminal is considered ground. The Feedback divider is than in such a way that the currents compensate. The floating regulators are a little difficult to understand, but they are quite common.

author: floobydust
author_rank: Super Contributor
timestamp: July 02, 2017, 02:06:33 am
content: Thanks Kleinstein, I had trouble because I also consider the failure modes for these lab PSU circuits. They aren't reliable IMHO. I've repaired many.Some people like to use the on/off switch on the power supply instead of disconnecting the leads.Then op-amp power +/-12VDC collapses before the main 35VDC. So -ve voltage backfeed into R19 and can damage U2, depending on CV potentiometer setting.Also, if power off/mains failure and battery/large capacitance load still connected, the op-amps have no power but voltage backfeed to the inputs happens.So I thought it would be beneficial to have extra series resistance in the voltage feedback. Like R21 20k, R22 10k giving 1/3 divider.This limits current into the op-amp's pins. You lose gain but I think there's plenty.
Can't find datasheet of IC "DAS05" - Page 1
Forum section: electronics / projects

author: jaipursky
author_rank: Newbie
timestamp: January 09, 2016, 06:37:55 am
content: Working on a Lenovo Laptop SMPS Power Supply and cannot find data sheet for this ICIts used in secondary section of the supply. Marking on the IC are below. Its 8 pin SMD. See Picture part number IC101.DAS05S967518TnD0401This IC is located near an Optocoupler and its driving it. In the first attempt it appears like an OpAmp but I am not 100% sure.Similarly there is another 6 pin IC with making "DAS2".Where can I find Datasheet for them? appreciate any help.

author: AhmedAbuShamla
author_rank: Contributor
timestamp: January 09, 2016, 06:44:14 am
content: if its near photocoupler then its probably like tl431 which regulates power using a voltage divider resistors
Can't find power supply kit Dave recommends - Page 1
Forum section: electronics / projects

author: Pjazz
author_rank: Newbie
timestamp: January 11, 2016, 07:24:30 pm
content: In the video blog, it was recommended to purchase a DIY power supply kit that had its own enclosure and a DC barrel connector so that it can be powered by a wall adapter. I have not found such a kit after two days of looking. Most often the circuit board is not enclosed and has screw terminals to house the wires. Do you know where you can find the power supply he suggests?Thanks!
can't home X on my printrbot simple metal (1403 revF)? - Page 1
Forum section: electronics / projects

author: Teljemo
author_rank: Contributor
timestamp: January 05, 2015, 09:35:13 pm
content: When I press home X.The taber moves, But as son as it pushes the end stop sensor it just freezes.. And I cand do anything more.. The software on the computer stops working..Y home woks fine if I run that first.. It goes to it's sensor, push it and goes back a bit..It wasnt like this at first.. I was doing my first print when the software stoped working.. After that.. I can't home X..What to do??

author: zapta
author_rank: Super Contributor
timestamp: January 06, 2015, 03:33:19 am
content: There are forums specific to printbot, probably better choice than eevblog.

author: Teljemo
author_rank: Contributor
timestamp: January 06, 2015, 09:11:44 am
content: I am talking about this problem in that forum to.I was just thinking that maybe it doesnt need to be a kabel spesific problem..I beleve some members of this forum probibly has 3d printers and there share of problems..So someone night know something about this home X issue im having..

author: Teljemo
author_rank: Contributor
timestamp: January 06, 2015, 02:51:12 pm
content: filmed it!I tried another computer and reinstalled the software..now I could go home sometimes.. but also Y started doing the same thing..here in the clip I sucsessfully get home first.. but the last just stops!
Can't understant from nxp datasheet... Are those 5VT pins available or not? - Page 1
Forum section: electronics / projects

author: JPortici
author_rank: Super Contributor
timestamp: July 26, 2016, 12:28:30 pm
content: I am to design a data logger for product testing (Basically Voltage/Current measurement of the target device power input, UART to receive data from the target device, RTC, external flash and usb to dump the saved data to a computer for analysis)I was thinking to use an ARM MCU for this project and between others i am considering using a NXP LPC11U68JBDxxI wish to keep the board dimension as small as possible, i would like to use the 48 pin LQFP package variant of the MCUbut looking through the datasheet I see that there are not many 5VT pins, and the indication is only put in the lqfp100 coloums.does this mean that all 5VT pins are only in the LQFP100? seem strange to me but better double checkThe need of 5VT pins comes because all the target boards are 5V powered. In theory only the UART pins will have to interface with the target board and I guess i could use a level translator but, again, tigh space, if i can get away with two pullups, that's betterProduct Page<- that's some ugly urlDatasheet-Reference Manual

author: Cervisia
author_rank: Regular Contributor
timestamp: July 26, 2016, 01:26:36 pm
content: As shown by, for example, footnote , these remarks are meant to apply to all three columns.So these pins are 5V tolerant in all three packages.

author: JPortici
author_rank: Super Contributor
timestamp: July 26, 2016, 01:31:18 pm
content: Of course. thanks, i was used to the foot note being present each time the condition was actually true
CANalyze: native linux CAN interface - Page 1
Forum section: electronics / projects

author: SenSeS
author_rank: Contributor
timestamp: April 27, 2017, 08:10:24 pm
content: Hi,I've made a native CAN to USB device for Linux. It supports both CiA DS102-2 type cables as well as the US style OBDII to DB9 cable. You can also set a termination resistor using a DIP switch. The reason I made this is because I wanted to analyze my car's CAN bus. In general I found slow hardware, mostly ELM327 based devices and mediocre software. I discovered that Linux has native CAN support via SocketCAN. This is great because it lets you treat a CAN interface like any other network interface. You can easily write your own programs using sockets. Multiple programs can simultaneously send/read data from the network. It's optimized for performance by using a binary protocol instead of the ASCII based protocol like ELM327 or Lawicel. In addition, the can-utils package offers clean and easy to use tools. For example "cansend can0 "123#010203" to send a message and "candump can0" to monitor messages. Most devices with native support Kvaser, Peak, EMS were too expensive for me. I just wanted an affordable device to work seamlessly with Linux's SocketCAN.If you're interested, you can find more info here:https://kkuchera.github.io/canalyze/. It's completely open source and you can make one using open source tools. You can find the hardware and firmware on github (see below). If you have any questions, remarks or if there's an improvement I haven't thought of, feel free to let me know!hardware:https://github.com/kkuchera/canalyze-hw/firmware:https://github.com/kkuchera/canalyze-fw/

author: seec
author_rank: Newbie
timestamp: October 17, 2017, 07:25:54 am
content: is it looks like /dev/can0 for linux kernel?(without drivers\kernel modules)

author: eliocor
author_rank: Unknown
timestamp: October 21, 2017, 03:48:33 am
content: I see your interface is using the 8dev device driver (usb_8dev.c): is it HW/SW compatible with theirUSB2CANinterface?
Canbus and using internal oscillator  - Page 1
Forum section: electronics / projects

author: Varys
author_rank: Newbie
timestamp: August 23, 2014, 07:46:13 am
content: I`m considering a uCdsPIC33EP128GP502with internal canbus and FRC oscillator. The FRC oscillator is specified with +- 1% tolerance (2% absolute tolerance). Reading various papers and website, I can't figure out if the this will work out well with canbus. I read that canbus works up to 1.5% tolerance, but don't know if these written values are absolute errors or +- errors.My requirements;50 kbaud bus speed will be more than suffice. Cable length will be 100 meters at maximum.Normally I always use an crystal oscillator for can bus, but due space constrains I have no other choice than go with canbus or change to another protocol e.g. rs485 and built a rs485->can gateway that can be placed elsewhere where the space is not so limited.I think I've found the answerFrom the microchip AppNote]: DS00754A-page 7:QuoteFrom this, I make up that it is the absolute error they are talking about. Meaning that the uC I mentioned is not within spec to use for CAN bus comm. This because there is a chance that node A is running at -1% of the oscillator speed, and another node at +1% of the oscillator speed.Also on: DS00754A-page 4:Quote

author: Mad ID
author_rank: Regular Contributor
timestamp: August 24, 2014, 03:50:21 pm
content: Yes, you must use a more stable oscillator. Oscillators can be very very small, you don't have to use a standard HC crystal
canbus, dashboard, halting communication from another device? - Page 1
Forum section: electronics / projects

author: JPortici
author_rank: Super Contributor
timestamp: February 02, 2017, 07:26:16 am
content: i want to write stuff on some car's dashboard display.from my investigation in these cars the display is controlled by a low speed can line from the body ECU, this line not connected to the CANB line on the OBD porthowever, there is a mode in which the display writes the info from the radio (frequency, station, cd/mp3/etc) this time available on the CANB line and because i'm lazy and i don't want to remove the covers, cut wire and install a small "filter" unit i just pretend to be the radio sending info.problem is, the radio transmits its state every 1 second or so (and whenever more info are needed), even when it's powered down, so i can't get a stable image even if i increase the message frequency to the point it's almost saturating the bus (which is bad practice anyway)i was wondering how to intercept/stop the radio messages without (again) putting myself in the middle and filtering it out

author: DBecker
author_rank: Frequent Contributor
timestamp: February 02, 2017, 01:53:00 pm
content: You seem to be asking if you can jam a specific CAN message.No, you can't effectively do that.The sender will keep attempting to retransmit, and you'll saturate the bus trying to repeatedly jam the signal.Eventually the sender will give up from too many errors, but you risk breaking vital functions before that happens. And after watching a modest amount of a successful traffic, the sender will reset and attempt to transmit again, repeating the risk to other traffic.

author: cat87
author_rank: Regular Contributor
timestamp: February 03, 2017, 06:48:34 am
content: The Dashboard and Radio are most likely on the same CAN bus, so there isn't anything you can do to stop it. If they were on different CAN busses, you might have had a chance by doing some quirky stuff to the car's gateway (hacking, reflashing, etc, but that is hard hard work) so the message does not get routed to its destination.If I read you query correctly, as an option, what you might want to do, (but this means tapping your own CAN transceiver onto the bus) is send your info to the dashboard. When the message comes from the radio, detect it with your uC and send your info message again, a few milliseconds after the radio status message was sent. That might just force the dashboard into displaying a continuous image.I can't really think of any other way to do this right now, but if I do, I'll leave another reply.
canbus questions/help - Page 1
Forum section: electronics / projects

author: sal_park
author_rank: Contributor
timestamp: April 04, 2015, 11:14:02 am
content: Hi all,long story short I've had anelm327 canbus readersetup on my car which has been working fine for several months. Thensomethinghappened and it stopped workingI've gone through everything I can think of, but still can not get it to work. Other devices on the canbus are still working, so I'm pretty sure that's not broken.I'm looking for any suggestions of what might be causing this - any comments welcome !This is what I've tried so far:1) A new ELM327 reader - connected it to the OBDII port to prove the reader works, connect it to the canbus directly, no output2) Connected an oscilloscope between CAN-H and ground and then between CAN-L and ground. I could see data activity on both CAN--H and CAN-L which was about 2v.3) Ground connection appears good, about 3 ohms or so between the ELM327 and ground.4) I could have buggered something up on the config of the ELM327 - I've got a new one in the post to test this thought.5) swapped CAN-H and CAN-L in case I wired them back to front - still no output.thankssal_park