hybridfree/eevblog-posts huggingface dataset:
PS/2 mouse/keyboard test software - Page 1
Forum section: electronics / projects

author: rfdes
author_rank: Regular Contributor
timestamp: September 01, 2019, 01:42:36 pm
content: Hi -I have a legacy project where I need to write some PS/2 firmware(mouse) for a client. The PS/2 interface has never had an official specification with a governing entity unlike USB (USB.org) although I have found plenty of literature on the subject. If I am wrong with this assertion please correct me. Anyway, I was hoping to find a software tool that would allow me to exercise my mouse PS/2 firmware and ensure that it will be *compliant*. I would have to believe that PS/2 device companies (Logitech, etc.) used something such as this when testing their PS/2 devices. They likely wrote their own custom software. There exists protocol analyzers for logic analyzers (I have one) but I want the software to have the ability to manually send/receive PS/2 host commands to a device (mouse, etc.).So, in lieu of writing my own (which I don't have the time) software does any know of a tool similar to what I have describes?Thanks for you helpJim

author: MosherIV
author_rank: Super Contributor
timestamp: September 02, 2019, 06:43:42 am
content: Hi.I do not know of any test software that does what you want.There is no official standard or body that defines the PS2 standard because it was copied from IBM.Technically IBM designed the format for their PS2 architecture of PCs and everyone else just adopted it, probably because the mini DIN connector was more conveinient than the old 5Pin DIN keyboard connector or 25w/9w Dtype for serial mouse.
PS3 Slim PSU hack - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: July 31, 2017, 03:58:07 pm
content: I managed to salvage the PSU from a friend's dead PS3 Slim and I want to use it as a desk power supply.Does anyone know how to wire this one up? I haven't been able to find the pinout for this board.

author: Kateh28
author_rank: Newbie
timestamp: August 01, 2017, 10:46:07 am
content: Is it safe to do? I heard that the PS3 had some major issues with overheating which often lead to the so called "Yellow Light of Death".

author: junits15
author_rank: Contributor
timestamp: August 01, 2017, 12:21:05 pm
content: Quote from: Kateh28 on August 01, 2017, 10:46:07 amIt should be safe, that was related to improper cooling of the main processors, not the power supply.OP if your ps3 still turns on I would snoop around while its running to try and figure out what the PSU module is looking for in terms of a turn on signal. Its really likely that there is a standby rail that runs all the time, and a main rail that comes on when the PSU is activated. If I had to guess you can probably get it to turn on by connecting two wires together. Optionally you can get an xbox 360 power brick for very cheap and those have a known pinout.
PS4 Controller Project - Page 1
Forum section: electronics / projects

author: rockbassist90
author_rank: Contributor
timestamp: May 17, 2016, 02:35:10 am
content: Hello, I have a perhaps out of the ordinary request. Are there perhaps any resources on how to control bluetooth devices via a playstation controller?Let me give an example. Hypothetically, I wanted to use the PS4 controller for a small DIY RC car...where would I start?PS4, Bluetooth Receiver, uController/Processor, just to name a few obvious integral hardware components/subsystems are to be considered.Any knowledge of this material? I greatly appreciate your advice in advance

author: bson
author_rank: Unknown
timestamp: May 17, 2016, 07:48:20 am
content: It looks reasonably well documented:http://www.psdevwiki.com/ps4/DS4-BTA microcontroller like a Cortex-M3 or MSP430 connected to a decent BT receiver module and a few PWM channels for servo control should be fairly straightforward.
pseudo-dopler direction finding - Page 1
Forum section: electronics / projects

author: cdev
author_rank: Super Contributor
timestamp: March 09, 2021, 10:11:43 pm
content: Hello, I would like to figure out a way to do pseudo dopper direction finding on HF. and figure out a way to visualize the findings.I have an HMC253 non-reflective eight way antenna switch I'd like to use, presumably with an array of four or eight identical vertical antennas. Does this seem like a fun project?So, I have found a bit more on it. Here is an old CQ magazine article on the technology,http://web.archive.org/web/20180820122315if_/http://www.n5dux.com:80/ham/files/pdf/DopplerRadio Direction Finder.pdfAnd finally, a Hackaday article on pseudo-doppler DF turned up.https://hackaday.com/2018/01/23/shmoocon-delightful-doppler-direction-finding-with-software-defined-radio/

author: LaserSteve
author_rank: Super Contributor
timestamp: March 10, 2021, 01:02:45 am
content: It is Wullenweber or Adcock Time, Maybe phased array....https://en.wikipedia.org/wiki/AN/FRD-10https://www.alarisantennas.com/products/active-adcock/https://www.w8ji.com/Goniometer%20adcock%20antenna.htmhttps://www.cyntony.com/blog/classic-df-antenna-mashupShould give you ideas.Steve

author: rfclown
author_rank: Frequent Contributor
timestamp: March 10, 2021, 01:44:49 am
content: I played with this a little bit many years ago. This is the first thing I threw together to look at the concept (after reading about it and thinking it sounded interesting). Only two antennas, but I could see it working. I couldn't tell if the target was in front of me or behind me, but I could definitely find the line to it by rotating the antenna. Small board with the SMA is the antenna switch. Resistors across the dipoles was to make the switch biasing easy. I just switched between the two and looked at the demodulated FM output with a modulation analyzer. (this was 915 MHz) I then made a board for more antennas, but never finished the project.I saw that some people used as many as 8 antennas, but I didn't understand the benefit. I think I build my board to accommodate up to 8, but planned to only populate 4 to start with. Simulating the expected results led me to believe that even three would be ok.I think the "Roanoke" doppler is a cool idea. Have fun.

author: cdev
author_rank: Super Contributor
timestamp: March 10, 2021, 11:32:40 pm
content: Thank you! This is very useful.I would really like to get this working on HF.It would be so cool to be able to visualize the signals on the hF bands by their direction of origin.Quote from: LaserSteve on March 10, 2021, 01:02:45 am

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: March 11, 2021, 12:01:13 am
content: One way to visualize a Doppler-type signal is to plot the demodulated IQ data as an XY graph. I do this on a CRT oscilloscope to look at Doppler signals from nanoparticles in liquids undergoing random motion and linear motion (due to an electric field). The graph will appear to rotate according to the Doppler frequency.
PSL-3604 upgrade to Dual 60V 6A - Page 1
Forum section: electronics / projects

author: Git
author_rank: Contributor
timestamp: February 02, 2022, 12:05:14 pm
content: I am upgrading Liv's PSL-3604 design to a dual 60V, 6A and modernising any components where necessary. If anybody has any known bugs can you let me know please. Thanks. I've simulated the upgraded model and it works fine. It will obviously need either two transformer/transformer combinations to keep isolation between the two channels. I could do it with lots of windings on one core, but that is messy and not just good transient isolation. For control I am thinking of having one CPU and opto-couple any control lines. For simplicity, and an obsession with doing things "properly", I am going to use SPI driven ADC's and DAC's with the SPI going through the opto barrier. Although not cheap, you can get 8 channel 16bit SPI DAC's for about 20 dollars which I think is ok. An added advantage, if you see it that way, is 1mV and 0.1mA setting resolution. I'll bring the outputs and sense lines to the front panel using safety 4mm sockets to ANSI/ESD S20.20:2014. I'm also going to use something like the LT4320 Ideal Diode Bridge Controllers for low loss rectification. I'm looking at needing maybe 5 or 6 voltage tiers to keep the dissipation down. Uprated FET's are needed which are easy to find. One thing that is bugging me with the model schematic and to a lesser degree the production schematic, is the 3 diodes in parallel with each of the voltage feeds from the rectification to the output FET drains. Anybody know why there are three?. I can't see any reason why one good rated Schottky won't do the job, but does somebody know otherwise?. I'm doing the whole thing in surface mount where possible. I use 0805 resistors and caps rather than the dust variety you can barely see. If you haven't done SM yet, it's nothing to afraid of. $10 stencils have made it reachable, along with modified toaster ovens for reflow.Any comments, hints, etc most welcome. I intend to make all the design data freely available, obviously.Git

author: Vovk_Z
author_rank: Super Contributor
timestamp: February 02, 2022, 08:27:46 pm
content: Quote from: Git on February 02, 2022, 12:05:14 pmWhat diodes are you talking about?psl-3604_sch.pdfVD12, VD15? Of cause, one good Shootky will do the job. I'm sure they all are added to schematics only to preserve a place onto an PCB to have a choice. You have to use (to place) only one of them - either TO220 case or SMD/SMT case (e.g. 30BQ100). Of cause more powerful ones are preferable. The more powerful - the better.

author: Git
author_rank: Contributor
timestamp: February 02, 2022, 11:12:39 pm
content: Of course!. I've done it many times myself on capacitors and through hole power resistors. As you say, CAD forces you to do it like that. You can create a multi-leaded footprint for a two pin component but it can also be a real hassle defeating the warnings and errors thrown at you. I really should have recognised that oneGit
PSoC 5LP VGA MiguelVP tutorial - question - Page 1
Forum section: electronics / projects

author: obiwanjacobi
author_rank: Super Contributor
timestamp: May 05, 2019, 11:26:25 am
content: First I would like to thank Miguel (@miguelvp) for his excellent work on this tutorial:https://www.eevblog.com/forum/projects/no-bitbanging-necessary-or-how-to-drive-a-vga-monitor-on-a-psoc-5lp-programmabl/?allI finally came around to playing with it and ran into an issue.I took the last full project code (zip 9) and added the DmaMain code to that - that works - after switching to the IMO (yes, it jitters like hell, but it works).Then I configured the VideoController (v1.0) to work for640x480@60Hzand changed the pixel clock to 25.175MHz (actually 26MHz, but my monitor seems fine with that), I got the PLL and MASTER at 76Mhz.I added a custom linker script because the command line option for splitting off CPU and DMA SRAM did not work for me (compile/link errors). I also moved the stack and heap to the CPU ".ram".I reassigned the pins to fit my test setup.That is were I noticed that only the start of each line is being written and characters are skipped. The rest of the line repeats the 'last' character for the rest of the line.After debugging and changing things around in order to understand what is going on I think the problem is that the line-DMA is writing it's bytes to the DMA_OUT Control Register too fast. If I increase the line-DMA burst from 1 to a higher number, less characters are displayed (per line) and more are repeated at the end (per line)...Question that arises is: Is there any way to sync clocking in bytes from (DMA) memory into hardware...?Context:My goal is to create a 80x+/-40 color character VGA device that can be driven by a Z80 bus.I would like to get rid of the line duplication and perhaps run with a (double) scan line buffer, instead of a (two) complete frame buffer(s).[Not sure what code to post, ask if you need more info]

author: obiwanjacobi
author_rank: Super Contributor
timestamp: May 08, 2019, 01:30:12 pm
content: There does not seem to be any other mechanism of synchronization between DMA and the hardware than the Bus-Clock.It is the Bus-clock that drives the DMA. So if you ensure that the Pixel-clock and the Bus-clock are the same (frequency) it seems to work.But the DMA is going way slower than it could be...
PSP Docking Station / RSM2257-G & WL8P153SNJ Datasheets - Page 1
Forum section: electronics / projects

author: paul_g_787
author_rank: Frequent Contributor
timestamp: May 02, 2020, 08:39:24 pm
content: Hi.I am attempting to fault find my recently aquired PSP slim docking station. The docking station has a remote control and unfortunately the remote is not operating the PSP.It is a Blaze 3 in 1 PSP Video Charging Dock as shown here:https://gadgetynews.com/blaze-3-in-1-psp-video-playing-charger-dock-supersize-your-psp-3000-vids-and-pics/There are two ICs onboard:The smallest is an RSM2257-G which I expect is an op-amp? I am not sureThe larger IC is a WL8P153SNJ which I expect is a programmable microcontroller used to receive the IR and send it to the PSP via serial.I am having trouble finding the datasheets for these ICs. Does anybody have these to hand or know where I might find them?Thank you

author: paul_g_787
author_rank: Frequent Contributor
timestamp: May 02, 2020, 08:40:28 pm
content: Attached is the least-blurry photo I could take.
PSPICE non sinking voltage source - Page 1
Forum section: electronics / projects

author: electronx
author_rank: Regular Contributor
timestamp: January 08, 2024, 01:45:32 pm
content: In an ideal world, most power supplies have a current sourcing feature but not a sinking feature. In this circuit, you can see that the 15V supply is sinking current. How can I prevent this in Pspice?

author: soldar
author_rank: Super Contributor
timestamp: January 08, 2024, 01:47:19 pm
content: An ideal diode?

author: MarkT
author_rank: Frequent Contributor
timestamp: January 09, 2024, 10:30:41 am
content: In an ideal world voltage sources are ideal and don't care about current direction. In the real world many voltage regulators can't sink current. There's certainly an ideal diode model for LTSpice, probably is for PSpice too. Maybe just use a voltage regulator model which may capture more real-world issues.
PSpice Simulation, AD8099 stuck in saturation with single supply - Page 1
Forum section: electronics / projects

author: MuriTheMyth
author_rank: Contributor
timestamp: January 02, 2024, 11:38:07 am
content: Happy new year guys!Have you guys worked with AD8099 before? Its data sheet says that AD8099 works with either +5/-5V supply or +5V single supply.When I'm doing simulation in PSpice, the Op-Amp works perfectly as expected in dual supply, but stuck in saturation when single +5V supply is applied, even though the output voltage should remain in the voltage swing range (see picture in attachment).The only difference is that supply at VEE pin is replaced with -5V. Is this a simulation error or is it out of AD8099's capabilities?Thanks for your time regarding my question.

author: magic
author_rank: Super Contributor
timestamp: January 02, 2024, 11:55:04 am
content: QuoteThis chip cannot work with inputs too close to the supply rails (in fact, very few can, so always look at this spec when selecting a part).In this case IN+<IN- but the output saturates to V+, which means that it has phase reversal.It happens and there is nothing you can do, save for providing at least -1V negative supply or using a different chip.editOpamps which work correctly with inputs down to the negative rail are marketed as "single supply", so this is the keyword to look for if you really need to do it on +5V alone.

author: MuriTheMyth
author_rank: Contributor
timestamp: January 02, 2024, 12:12:23 pm
content: Thank you for your advice! I guess I will just go with dual supply then.

author: berke
author_rank: Frequent Contributor
timestamp: January 02, 2024, 12:59:40 pm
content: Quote from: magic on January 02, 2024, 11:55:04 amRegarding another marketing term, does "rail-to-rail" apply to inputs, the output or both?
PSpice simulation for S-R Latch not stopping - Page 1
Forum section: electronics / projects

author: MuriTheMyth
author_rank: Contributor
timestamp: January 03, 2024, 01:54:06 am
content: Guys happy new year. I have been trying to do simulation for SR latch built from nor gates in PSpice and I set the transient stop time to be 1000ns. However, the simulation do not stop at that time, and I checked the simulation window which says stopping at 0.01s. It will definitely take days for my computer to do that.The nor gate used for simulation is SN74AHC02A from Texas Instrument and the model they provided is behavior model in .cir format. I tried to remove the SR latch circuit from the simulation or doing simulation just for a single nor gate, which all went normally.Do you have any idea what's happening here? I'm very grateful for your help.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 03, 2024, 02:22:31 am
content: Try removing the trailing "s" in the "Run to time" edit field. (So just input "1000n".) I bet this trailing "s" confuses it. Yes, it shouldn't. Software. Let us know if that fixes it.

author: MuriTheMyth
author_rank: Contributor
timestamp: January 03, 2024, 02:35:05 am
content: Unfortunately no. The behavior of simulator is mostly the same when s is removed.
PSR flyback transformer calculations - Page 1
Forum section: electronics / projects

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: July 08, 2019, 10:15:43 am
content: Hi,I have bought some LP3783BM from lcsc, and now I'm testing them for now, I have prepared a spreadsheet based on an1028 from BCD Semiconductor Manufacturing, which I have attached it,I have build and tried 3 different transformers, the transformer is EFD15 and I got it from a no brand supplier in china, my first problem is how to extract the core properties?also I have winded 3 transformers, I can get around 7W out put for these configuesfirst configNp =110 turns and wire size 0.12mm Naux = 26 turns and wire size 0.12mm Ns = 19 and wire size 0.45mm, I assumed Efficiency = 0.85 and the Switching Frequency = 85KHz in this config the output is around 7WSecond configNp =79 turns and wire size 0.12mm Naux = 21 turns and wire size 0.12mm Ns = 16 and wire size 0.45mm, I assumed Efficiency = 0.8 and the Switching Frequency = 110KHz in this config the output is around 7WFor the first two configs the transformer gets hot around 25-30C above ambientThird configNp =57 turns and wire size 0.35mm Naux = 15 turns and wire size 0.12mm Ns = 11 and wire size 0.45mm, I assumed Efficiency = 0.8 and the Switching Frequency = 155KHz in this config the output is around 6W and the transformer gets very hot, I think in the order of 60C-70C above ambientAlso the output is around 7.5W at the beginging and when the things warms up it goes around 6.7WI have seen they could done it around 10W with an EFD15 core size, so I want to increase the output power to 10W, do you have any Ideas?Also I have calculated the upper feedback res to be 4.4K but I have put a 4.99K res to get 12V at output any Idea?for now I have only 0.12mm, 0.35mm and 0.45mm wires, so is it possible to do it with these wires?The circuit diagramThis is how I placed the air gap with some tapes to get the primary inductance near what's calculated, note that this is for the second config and it's slightly lower, but for the first config and the thrid config I was very close, almost what's been calculatedThis is my active load and the output voltage and current for the second config and when the cicuit starts up and it's coolAnd here is the output dropped about 1V and it has passed about 15 minutes, and the circuit warms up.The circuit itself on a proto boardTop of the boardBottom of the boardAlso mornsun-power has some EFD15 cores that they claim they can output 10W,https://www.mornsun-power.com/html/product/AC-DC-Transformer.htmlSo how can I get better efficiency? and calculate the core properties and calculate the transformer correctly? what am I doing wrong?

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: July 10, 2019, 06:25:14 am
content: How can I increase the output power? any Ideas?
PSRAM Layout Considerations - Page 1
Forum section: electronics / projects

author: Evan.Cornell
author_rank: Regular Contributor
timestamp: August 26, 2020, 12:23:29 pm
content: I am working on a design with STM32H743 and IS66WVE2M16EALL-70BLI (32Mbit PSRAM). Since the PSRAM part has a max page access time of 70ns, I assume that means the fastest I could read guaranteed data out would be 1/70ns = 14.2MHz.In terms of the hardware design, this isn't very fast at all, so am I correct in thinking that I don't need to be particularly careful about either length matching or impedance controlling all the signals between the STM32 and the PSRAM part?

author: David Hess
author_rank: Super Contributor
timestamp: August 27, 2020, 02:27:50 pm
content: Quote from: Evan.Cornell on August 26, 2020, 12:23:29 pmThat is correct, with the caveat that fast edge speeds still need to be accounted for. 70 nanosecond access times were handled by TTL technology decades ago which gives some idea of the required design rules.Access times for DRAM have not scaled up nearly as much as clock speeds over the decades so design rules are much more stringent now for what is essentially the same access time.
PSRAM memory | ESP32 - Page 1
Forum section: electronics / projects

author: ranganatennakoon
author_rank: Contributor
timestamp: April 17, 2021, 03:35:48 pm
content: I'm engaged in ESP32-CAM project, AI Thinker schematic has IPS6404LSQ ps ram but cun't find it. so my question, is IPS6404LSQ and ESP-PSRAM64H completely compatible??help methanks

author: ranganatennakoon
author_rank: Contributor
timestamp: April 19, 2021, 03:07:41 pm
content: BUMP !

author: exe
author_rank: Unknown
timestamp: April 19, 2021, 03:17:59 pm
content: Afaik, ESP-PSRAM64H is a relabeled another chip, but I don't remember which one. If they have same voltages and timings, then I'd say it's drop-in replacement. Did you check datasheets?

author: Mariko
author_rank: Newbie
timestamp: April 19, 2021, 04:11:29 pm
content: From what I saw in datasheets, they are identical, pins are the same and commands too.

author: ranganatennakoon
author_rank: Contributor
timestamp: April 24, 2021, 09:54:48 am
content: yes pin configuration is same

author: ranganatennakoon
author_rank: Contributor
timestamp: April 24, 2021, 09:56:08 am
content: yes I think so

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 24, 2021, 09:29:09 pm
content: Yes they are compatible. Those are the same chips that can be used on the Teensy 4.1.
PSTN gateway E1 framer/deframer chipset - Page 1
Forum section: electronics / projects

author: rakeshm55
author_rank: Regular Contributor
timestamp: March 10, 2017, 04:13:43 am
content: Hi,I was in the process of designing a PSTN gateway which was previously using PEF22554 chipset(Infineon)(4 E1 channels)....due to obsolescence I was in search out for a replacement chipset for which i have shortlisted XRT86VX38,XRT86VL34IB,IDT82P2284 or IDT82V2084....though I am not sure about the lifetime of these chipsets.....E1 being archaic should I opt for newer versions of technology (E2,E3,E4) do they have backward compatibility ??....Since I am in for a new board+ what should be my way to go for availability of chipset, lifetime and cost effectiveness....
PSU 5V out is 5.26V - is that allright? - Page 1
Forum section: electronics / projects

author: shadewind
author_rank: Frequent Contributor
timestamp: May 07, 2011, 09:22:47 pm
content: I got myself a Caltek PSM3/2A which is rather nice for the price I suppose (a Chinese brand, surprise) which arrived home with UPS yesterday. The adjustable outputs measure very well compared to my Agilent U1242B but the fixed 5V output measures around 5.26V pretty much regardless of load. I know it's a cheap PSU but is this really fine? Will this work anyway for most chips or should I worry about it? Anything I can do?

author: Bored@Work
author_rank: Super Contributor
timestamp: May 07, 2011, 09:50:12 pm
content: Quote from: shadewind on May 07, 2011, 09:22:47 pmWhen it is within specs it is formally fine. What do the specs say? For my liking +260 mV aren't fine.QuoteThis depends on the chips, but many 5V should be able to survive this. You definitely lose headroom when it comes to the maximum rating of 5 V ICs.QuoteI would at least be careful. That voltage is, for example, at the upper limit, if not above, what a typical 7805 regulator would deliver.QuoteCheck the specs. If it is out of spec one option would be to return it.If it is within spec, you could of course open it, see how they internally generate the voltage and, depending on how they do it, adjust or alter the circuit. You will lose your warranty.

author: shadewind
author_rank: Frequent Contributor
timestamp: May 07, 2011, 10:29:51 pm
content: The manual says for CH3 "Voltage range: 5V (±8%)" which is quite an odd way to put it but in that case it's definitely in spec. Well, you get what you pay for I suppose. I doubt I could find something better without going to a significantly higher price.

author: dayve
author_rank: Newbie
timestamp: May 09, 2011, 02:48:21 pm
content: Check this out:http://www.rcgroups.com/forums/showthread.php?t=1030827Based on the last picture, it looks like it may be adjustable. He doesn't have anything shown for CH3, though. Based on the other pictures, I'm guessing that picture is of a slightly different model that doesn't have a CH3. I see a few empty spots, though, so maybe CH3 is implemented the same way. It might be worth checking out if you don't mind voiding your warranty.
PSU Automated tester : xDevs.com Neutron or practical DC load design  - Page 1
Forum section: electronics / projects

author: TiN
author_rank: Super Contributor
timestamp: December 16, 2015, 04:48:43 am
content: Hi all,Since DC load topics are often pop up here and there on EEVBlog, let me add some into mixture as well.I hope fellow volt-nuts would not judge this one too hard, but I decided to open my old ATE design, which I did in 2008 or so. There is no precision better than 1% in this one here, but it have 2000W of capacity!Back then I had part-time job as reviewer on few PC websites, covering PC PSU evaluation and testing. All I had was a cheapie DMM and Tektronix 2246, which is not enough to do proper power supply testing, so I ended up with need of multichannel high-power DC load very quickly. Quick evaluation of market shown that I had no way in hell to get any of those multichannel beasts from Chroma and such with regular student money. Solution? If you can't buy it, make it!Version 1Hence the prototype was born, using MOSFET, CPU fansink, and bunch of opamps. I was into learning MCUs and programming them same time, so it was obvious to mix both together and make automatic DC loader/PSU tester. Bunch of MOSFETs in progress were burnt, of courseIt ended up using IR FB180SA10P ISOTOP-package mosfets (really nice beasts, but expensive), ATMEL ARM7 MCU and multichannel 8bit DAC. No precision stuff, I barely knew anything about analog back then (not that I know a lot now either!).That thing worked, but was not so easy to use, as often some wires were getting loose, or some other bugs haunted it.Version 2So I redesigned whole thing, and called it Neutron, as it was second iteration (first one was Proton).Nice 4-layer PCB now, with all connector front end and measurement circuitry on same board. The only thing left externally are actual power MOSFETs with their current shunt resistors.Software was revamped too, with great help by friend of mine, which works as back-end web developer and have no idea about any of embedded stuffAs a result, whole thing was making pretty graphs like this one:All design details, schematics, firmwares, softwares, dozens of photos and files for grabs are available inarticle on my site.Hope you like it

author: Vgkid
author_rank: Super Contributor
timestamp: December 16, 2015, 04:57:10 am
content: Nice job. If you dont mind me asking, where/who did you review for?

author: TiN
author_rank: Super Contributor
timestamp: December 16, 2015, 05:00:31 am
content: Russian website mostly, overclockers.ru.

author: lukaq
author_rank: Regular Contributor
timestamp: December 19, 2015, 05:13:11 am
content: I seen this long ago, I really liked it, a lot of work. Software was also simple. Kinda wish I had this right now.Good job Tin
PSU CV CI Howland - Page 1
Forum section: electronics / projects

author: iMo
author_rank: Super Contributor
timestamp: March 04, 2019, 06:50:39 pm
content: This is follow up of the topic Zero999 has started here:https://www.eevblog.com/forum/beginners/0-30v-0-3a-psu-audiogurus-version/msg2240139/#msg2240139It is a pretty interesting schematics, needs some elaboration however, therefore let us continue here.The voltage and current could be set via DACs easily.

author: iMo
author_rank: Super Contributor
timestamp: March 04, 2019, 06:54:30 pm
content: And the ADI stability test (with lower values in dividers).

author: iMo
author_rank: Super Contributor
timestamp: March 04, 2019, 07:20:17 pm
content: Transient with switching Rload 10ohm/1ohm, Cload made of 3 capacitors, Vout=15V, current limit=2A, OP27.

author: iMo
author_rank: Super Contributor
timestamp: March 04, 2019, 07:36:41 pm
content: Stability with OP27. A perfect oscillator. Phase margin close to 0deg.Interestingly in transient with the Iload switching 1.5A/15A there are no oscillation visible. Hmm.

author: iMo
author_rank: Super Contributor
timestamp: March 04, 2019, 08:18:10 pm
content: Constant load 5ohm, switching Vset 0.5/2.0V for Vout 5V/20V while I_limit is 2A. Nice, except a small transient at the rising edge of the Vout and I(R_Load).
PSU design question (analog vs. digital control) - Page 1
Forum section: electronics / projects

author: homebrew
author_rank: Frequent Contributor
timestamp: January 04, 2014, 10:40:58 pm
content: Perhaps a stupid question but why are Dave and other Lab-PSU designers using analog control circuits for voltage and current regulation? In all designs that I am aware of, the microcontroller 'only' sets the desired voltage and current through DACs and the actual regulation part is done in analog hardware.Why not just do proper PID control in software? The uC could sense current and voltage and drive the series pass transistor through a single DAC (or even PWM).The big advantage would be that the system could be parameterised completely in software for both accuracy as well as stability. And it might also even be cheaper ...I don't like to believe that this is a safety thing. If the controller goes bust in the traditional circuit, it could also set an undesired voltage to the output ...Is there any real reason?

author: Dave
author_rank: Super Contributor
timestamp: January 04, 2014, 10:48:58 pm
content: Not fast enough. An analog feedback loop will always be faster than an ADC + data processing + DAC.

author: homebrew
author_rank: Frequent Contributor
timestamp: January 04, 2014, 10:55:21 pm
content: Quote from: Dave on January 04, 2014, 10:48:58 pmThat's certainly right but what is fast enough? 0.5MSPS + Processing for example seems very doable on nearly any modern uC ...What would your estimate for a minimum sampling and update rate?

author: Dave
author_rank: Super Contributor
timestamp: January 04, 2014, 11:06:23 pm
content: A few microseconds, tops.That would have to be the time from measuring a change, to applying the appropriate correction to the DAC.

author: tszaboo
author_rank: Super Contributor
timestamp: January 05, 2014, 12:24:23 am
content: Quote from: homebrew on January 04, 2014, 10:40:58 pmYes, the reason is that it is way too easy to solve the problem with two resistors. There are countless analog power supplies, which have everything built it, and I can design a new power supply in an hour if I really want. With a microcontroller, you need an external switching device, usually a driver for it, voltage sensing for the feedback, programming port for your micro. Also, you need to take care, so a breakpoint doesnt blow up your carefully designed power supply, or it doesnt blow up the first time you power it.And then you also need an extra power supply, just for the microcontroller.Besides, digital control is slower than analog. And you can make a decent PID with 3 resistors, capacitors and an opamp basically.And after you designed it, you need to characterize your supply, which is already done if you use an off the shelf IC.
PSU for small DC brushed motors - Page 1
Forum section: electronics / projects

author: adauphin
author_rank: Unknown
timestamp: February 06, 2022, 10:45:24 am
content: With the kids getting into engineering classes at school, I would like to acquire a PSU that can run small DC motors in the 0-12V range. Safe bet a bench linear PSU for circuitry work is not ideal for this application.I have an old RC battery charger that does motor break-in but it's not variable voltage on the fly.I know there's tons of PSU's out there, I have no idea where to look.A dual output, 0-12V, maybe 5A max, more the better but doubtful I would even need 5A but for brushed motors who knows.The option of brushless would be nice.Budget....I guess under $100 but again, this is one area I have no knowledge of where to look.I appreciate any input.
psu ic sub - Page 1
Forum section: electronics / projects

author: m3vuv
author_rank: Super Contributor
timestamp: January 12, 2022, 12:42:01 am
content: Just wondering if i can use an infinion SG3532J instead of an lm723 in this psu schematic,if so any changes needed?

author: m3vuv
author_rank: Super Contributor
timestamp: January 12, 2022, 12:42:40 am
content: heres the datasheet

author: coromonadalix
author_rank: Super Contributor
timestamp: January 12, 2022, 01:45:30 am
content: should be a drop in replacement, with improved voltage input up to 50 volts ........ the datasheet says it all

author: m3vuv
author_rank: Super Contributor
timestamp: January 12, 2022, 02:03:25 am
content: if i remember it has another opamp for the current sense so i gather a lower value current sense resistor can be used,not sure about the 50v input tho,these chips are hard to find and expensive,so dont want to blow it up!,i want to use this to build a lab psu with cc/cv but adjustable from say 3v-30v and say 100ma to 15/20 amp,i have a transformer with multiple taps to do this,any advice welcome.

author: coromonadalix
author_rank: Super Contributor
timestamp: January 12, 2022, 12:13:40 pm
content: with theses specs the venerable lm723 will do perfectly BUT the max input is 40 voltsIf you dont go down to zero volts the design will be much simplerTons of schematics on the web to help you design a good psuThe tricky part will be to have an voltage(s) comparator(s) circuit to help switch the socondary xformer taps

author: m3vuv
author_rank: Super Contributor
timestamp: January 13, 2022, 12:39:40 pm
content: ive always found the 723 to be weak insomutch as needing .6v before foldback/ current limiting,the infinion ic seems better by needing a lower value current sense resistor to get current limiting out of the box without external opampl on the current sense curcuitry?,ie,making it better for a wider current controle range.
PSU output circuit - whats the function? - Page 1
Forum section: electronics / projects

author: JJalling
author_rank: Unknown
timestamp: February 26, 2017, 11:00:06 am
content: Hello all,I'm looking at the schematics of a smps design from TI (https://www.ti.com/seclit/df/tidrlm1a/tidrlm1a.pdf), but I cant figure out what the functionality of the highlighted section (see attachment) of the PSU is (page 2 of the schematics).Can someone please give a quick explanation?Thanks, BR Jonas
psu pass transistor emitter resistors - Page 1
Forum section: electronics / projects

author: p.larner
author_rank: Frequent Contributor
timestamp: March 25, 2024, 05:18:02 am
content: On some i see 0.1 ohm used others use 0.22 ohm,why the difference even tho the same pass transistors are used?.

author: Xena E
author_rank: Frequent Contributor
timestamp: March 25, 2024, 05:46:40 am
content: Quote from: p.larner on March 25, 2024, 05:18:02 amSpecific examples? Schematics?Current sampling? or emitter degradation for balancing?First instance: value depends on direct sampling level required.Second instance: design choice based on pass device specifications, covering expected spread between parralel devices, and how many there are.Regards,X.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 25, 2024, 08:58:27 am
content: The required size of the emitter resistors to improve current sharing depends on the heat sink (thermal coupling) and spread or parts, but also the voltage (higher voltage needs higher resistors). The choice is often more like a rought estimate and some prefer smaller values as this can use lower power parts in the hope to have matched transistors, while other play it safe and use larger resistors.Even with a perfect match to start with on still needs the resistor as the system can become unstable (positive feedback with too much gain) and run away with too little resistance.

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 09:12:48 am
content: I bet this is about the 723 again isn't it? I repeat. You'll get better responses by keeping it all to one thread!In many circuits, the emitter resistors also double as current sense resistors. This is common in linear regulators, as well as amplifiers which have over-current protection. In some cases, the current limit circuit is only connected to one of the resistors, but it's often better to connect it to all of them, each via another resistor, to get the average of all of the currents.

author: iMo
author_rank: Super Contributor
timestamp: March 25, 2024, 09:24:05 am
content: Quote from: Zero999 on March 25, 2024, 09:12:48 amThe OP has got this message several times already, afaik, still polluting the forum with new threads..

author: Xena E
author_rank: Frequent Contributor
timestamp: March 25, 2024, 10:16:26 am
content: Quote from: iMo on March 25, 2024, 09:24:05 amJust realised, seen them in Beginners, Projects, and Repairs, mostly post and run. Perhaps the OP is a blanket bomber: posts the same Qu's across several sites and forums then forgets~•~•~•~•~•~•~•~•~
psu pass transistor sub - Page 1
Forum section: electronics / projects

author: p.larner
author_rank: Frequent Contributor
timestamp: March 17, 2024, 12:01:12 pm
content: I am building a linear psu,normaly it uses 2X TIP 3055 items can i sub t4hem using 2X BUW-49 TRANSISTORS INSTEAD,WOULD THEY BE MORE ROBUST?,its a linear psu.

author: wraper
author_rank: Unknown
timestamp: March 17, 2024, 12:12:28 pm
content: BUW49 is marketed for switching applications only and its specs are all around that. Also weirdly none of its datasheets have current gain spec. No, I suggest refraining from using it for any linear applications.

author: BrokenYugo
author_rank: Super Contributor
timestamp: March 17, 2024, 01:14:26 pm
content: ALL CAPS IS EQUIVALENT TO YELLING, PEOPLE DON'T LIKE BEING YELLED AT, LESS YELLING WILL TEND TO RESULT IN MORE HELP.The pass transistor(s) in a linear supply are supposed to have a DC safe operating area on the safe operating area graph, that's the thing you're looking for in the datasheet. Most power transistors designed/marketed for switching aren't specified for linear/DC use though some older ones are. Be careful with that, stuff can be redesigned, a 20 year old datasheet from brand A does not guarantee performance of a new part from brand B.

author: David Hess
author_rank: Super Contributor
timestamp: March 17, 2024, 09:43:08 pm
content: The current gain is suppose to be about 40 at 5 amps. The real unknown is the safe operating area, but the power rating is 150 watts instead of 115 watts, so I suspect it will be fine. The higher frequency is more likely to cause local oscillation, so maybe include base stopping resistors or ferrite beads.

author: p.larner
author_rank: Frequent Contributor
timestamp: March 17, 2024, 10:53:13 pm
content: thanks for the answers,my kb was playing up,didnt mean to be rude ie caps lock.
psu regulator ic supply - Page 1
Forum section: electronics / projects

author: m3vuv
author_rank: Super Contributor
timestamp: March 12, 2022, 09:36:42 pm
content: Hi all,i am building a bench psu (variable),the transfo is from a palstar ps-30 psu,it has an auxillary winding,i plan on using that to power the regulator ic(infinion sg3532)I have a couple of questionsA,am i best using a 78 series regulator to power the ic?B,can it be a lower voltage than the main psu output?TIA.

author: m3vuv
author_rank: Super Contributor
timestamp: March 13, 2022, 07:44:29 am
content: can no one advise on this?.

author: inse
author_rank: Super Contributor
timestamp: March 13, 2022, 09:17:46 am
content: All the application drawings in the datasheet have the IC (Linfinity, btw.) supplied by the input voltage.If you look at the block diagram, you will notice that the driver is tied to the Vin and thus cannot drive a highside transistor above that voltage.If you plan on using a PNP, you will encounter a low voltage limit.
PSU Repair - Page 1
Forum section: electronics / projects

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 14, 2022, 01:43:17 pm
content: Didn't take any pictures or measurements, and not worth like writing up anything. Just thought this was odd enough to share.PC shut down suddenly.Power button doesn't seem to do anything.Standby power still on (LED on motherboard).Oh that's interesting, standby still on... wait, it's being back-powered from my USB hub? Oh that's... probably not good.Unplug that, standby confirmed still good, goes up and down (down very slowly of course) with PSU.Now pressing power button makes the fans twitch just a little bit. Hmm. Cycle PSU power then get one press again. Seems like a latched fault?Main power maybe borked, that's not great.Take PSU out, test on bench.Pulling PWEN# indeed makes the outputs light up momentarily.Probing the outputs, 5 and 12V look good, 3V3 is shooting up to 4.2V peak though, yikes. Okay, so the voltage monitor is doing its job, that's... good.Further probing, the 3V3 regulator (a TL431) is clearly getting Vsense, the divider measures right, and it's even turning on as voltage rises above 3.3V.And the transistor it's driving (a PMBT2907A), seems fine on diode test, and all the connected resistors measure as labeled.And yet, probing across the actual transistor during startup, there's 1, almost 2V peak across E-B.Replace it with a MMBT4403. Starts up just fine.So, freak failure of a SOT-23 PNP in the voltage regulator circuit. No apparent cracked solder joints, or open or short or blown components. Weird.For those curious, it's a EVGA 80PLUS 500W supply. Quite old at this point, but still going strong, it seems. Not sure how much power I run at normally but it's hardly stressed, the fan barely runs. Does have a Capxon (post PFC / main bulk cap) and Teapo (everything else), none of which are bulging or leaking. They're probably rated alright for the design (3 year warranty). Curiously I've had to repair it twice before, one more or less as expected (replace the shitty fan), the other a freak incident (blown fuse, nothing else!?).Tim

author: Vovk_Z
author_rank: Super Contributor
timestamp: October 14, 2022, 07:53:07 pm
content: I would check caps and replace them to solid polymer ones when possible.
PSU Sony APS-211 (Cisco):: looking for manual and datasheet - Page 1
Forum section: electronics / projects

author: 0db
author_rank: Frequent Contributor
timestamp: October 13, 2020, 03:28:08 pm
content: The Sony APS-211 looks like a 1400W PSU made for some CISCO's equipment.I'd like to reuse it for a CNC because it has a 42V line able to provide more than 20A.Unfortunately I can't find any datasheet or manual

author: bingo600
author_rank: Super Contributor
timestamp: October 13, 2020, 06:04:36 pm
content: Are you sure it's a 42v line ?48v (PoE) would seem more likely in a CiscoBut then again , if it's one of those 1300w "Square Metal modules w. a handle across the front" (for the 45xx or 65xx), it could be ..../Bingo

author: 0db
author_rank: Frequent Contributor
timestamp: October 13, 2020, 09:21:07 pm
content: Quote from: bingo600 on October 13, 2020, 06:04:36 pmIt's the only thing written on the label: 42V line, 60A. And there is a big custom connectors with several pins. Also, it doesn't poweron when you connect it to the 230VAC. I think it's like ATX PSUs: probably some "poweron" signal is required to switch it on.

author: 0db
author_rank: Frequent Contributor
timestamp: October 15, 2020, 01:20:48 pm
content: Yesterday I opened it. Now I am 60% ready with it. At least I have already found how to poweron. There is a Poweron signal

author: coromonadalix
author_rank: Super Contributor
timestamp: October 16, 2020, 04:50:09 pm
content: check on rcgroup you may find infos ??https://www.rcgroups.com/forums/showthread.php?1292514-How-to-convert-Server-Power-Supplies

author: hell_hound
author_rank: Newbie
timestamp: December 07, 2024, 01:28:52 pm
content: Hey 0db how did you manage to get the PSU to start?
PSU super clean and stable design - Page 1
Forum section: electronics / projects

author: isopropilick
author_rank: Contributor
timestamp: October 26, 2015, 09:39:07 pm
content: I want to design a bench psu but the first step to do it is a stable base main power supply, i want to know what i need to consider and if possible a base design of a source of 40v DC

author: mariush
author_rank: Super Contributor
timestamp: October 27, 2015, 01:35:46 am
content: Here's a schematic for a 50v 1A adjustable linear power supply... attached to the bottom of this post.As you can see, such power supplies use custom transformers with multiple windings, and connect these windings in series using relays as needed (to keep the input DC voltage just a bit above the user configured output volage).There's also separate winding for the opamps and for driving those relays.Also attaching a HP power supply "operating and service manual", which contains a schematic list of parts . Hope it may help.
psu used - Page 1
Forum section: electronics / projects

author: m3vuv
author_rank: Super Contributor
timestamp: April 22, 2022, 07:06:40 pm
content: a few weeks ago i brought an industrial non working psu(switcher) it has 2 outputs at 15-18v at 8 amps adjustable,also two rails at 5v adjustable at 65 amps,any ideas what would of used this setup?.65a at 5v seems wierd to me.

author: Gyro
author_rank: Super Contributor
timestamp: April 22, 2022, 07:11:27 pm
content: Possibly a Minicomputer (not a PC). Something with lots of 5V logic anyway.