hybridfree/eevblog-posts huggingface dataset:
SSR selection for AC/DC switching, alternate topologies - Page 1
Forum section: electronics / projects

author: gr8BlueSmokeEscape
author_rank: Newbie
timestamp: September 02, 2022, 03:55:02 pm
content: I would like to switch AC and DC from a common bus for multiple digital outputs (user requirement, not my idea). The end use case is a digital out from a ucontroller controlling a relay that could switch either 120VAC 0.6A or 24VDC 3A through a normally open SSR from a common bus powered by a spring clamp connector entry on the PCB. My question is whether an SSR exists that could satisfy these requirements under $30. I found AQZ207G from Panasonic which is 200 VAC/VDC 2A, however that does not get me to the required 3A. For AC the typical configuration for an SSR is triac, thyristor, etc and for DC is IGBTs or mosfets as far as I can tell. Is there a specific SSR topology that can handle both AC and DC? Alternatively, if you can think of a different device or solution to this issue I would be very grateful!

author: Benta
author_rank: Super Contributor
timestamp: September 02, 2022, 05:59:49 pm
content: Is SSR a customer requirement?A normal electrmechanical relay would do this with ease and costs a fraction of $30.

author: gr8BlueSmokeEscape
author_rank: Newbie
timestamp: September 02, 2022, 07:31:47 pm
content: It's my aim at getting close to their max switching frequency specification. I understand that there is no way they are ever going to utilize it at 100 Hz, nor can an SSR handle 100Hz smoothly, but I'm absolutely sure a mechanical relay would not be able to handle 100 Hz! I think most of the issue here is customers making requirements documents without having a proper sitdown beforehand. I just talked them into dropping the 3A requirement which would have been used to drive some solenoids in favor of external interposer relays, so I think I'll consider the issue solved. However, if you have any insight on SSR AC/DC architecture it would be much appreciated from a more intellectual frame of reference.

author: Benta
author_rank: Super Contributor
timestamp: September 02, 2022, 08:57:28 pm
content: Solenoids at 100 Hz?Before you do any more work, you need face time with this customer.

author: szan
author_rank: Regular Contributor
timestamp: September 04, 2022, 09:36:05 pm
content: Using MOS-GATED power transistors in AC switch applications:https://www.irf.com/technical-info/designtp/dt94-5.pdf

author: Zero999
author_rank: Super Contributor
timestamp: September 05, 2022, 05:00:05 pm
content: Quote from: Benta on September 02, 2022, 08:57:28 pmIt's possible to PWM a solenoid to use less energy to keep it in the activated state, which could be the application. It's also possible he's confused with the switching frequency and the highest possible AC frequency of the current being switched.Quote from: gr8BlueSmokeEscape on September 02, 2022, 07:31:47 pmThe easiest way is an isolated DC:DC converter, a MOSFET driver and MOSFETs.
ST L7987 buck converter for 48->12V supply - Page 1
Forum section: electronics / projects

author: uer166
author_rank: Super Contributor
timestamp: February 06, 2020, 06:46:40 pm
content: I need a (40V~55V)->12V supply at 2A that will power 12V motors and 2 other DCDC converters to 3.3V and 7V that need 200mA each. Looking at ST's L7987 it seems perfect, but a few things stand out. It has a voltage-mode control loop that externally compensated. I like that it's external compensation since I want to tune it to play well with downstream buck converters, but heard bad things about voltage control loops here.It does have a cycle-by-cycle current limit (doesn't play a role in control), as well as foldback, but it seems to be disabled during the soft-start phaseHas anyone used one of these parts with success?https://www.st.com/resource/en/datasheet/l7987.pdf
ST Link V2 Clone - Plus - Page 1
Forum section: electronics / projects

author: canadianjerk
author_rank: Newbie
timestamp: February 17, 2018, 04:18:59 pm
content: Hello everyone, first post on the forum! Woohoo! So, I've designed a st link v2 clone that has a few extra features for when I develop STM32 and STM8 devices. My question then, would I get in trouble or is there any potential legal issues I could be faced with if I were to try and sell my clone?Thanks,

author: Jeroen3
author_rank: Super Contributor
timestamp: February 17, 2018, 04:39:32 pm
content: Are you going to sell it asST Link V2 Plus?

author: canadianjerk
author_rank: Newbie
timestamp: February 17, 2018, 04:45:28 pm
content: QuoteWas thinking about it, unless I'd be violating some copyright laws or something.Edit: spelling error
ST-LINK/V2-1 stub from NUCLEO dev board - using it + serial port? mounting it? - Page 1
Forum section: electronics / projects

author: incf
author_rank: Frequent Contributor
timestamp: May 30, 2025, 02:34:07 pm
content: I'd like to know if anyone has had success in making use of the ST-LINK/V2-1 break-off PCB from NUCLEO dev boards.I've got a situation where I'd like to have 3-4 different STM32 programmers and 3.3V serial ports operating simultaneously. I have several dev boards laying around, and they seem to have exactly what I need on them.I have not seen very much discussion or information published for the V2-1 programmer. Although schematics have been released by ST. I've got a few questions.In a low volume commecial test jib: How would you go about mounting one of these programmer PCBs? Hot glue? Zip ties? Carefully drill a hole in it and screw it down?What is the purpose of the pair of two pin headers the are connected to ground? Mounting? Probing?Does anyone know what the max baud rate is for the integrated serial port? I wonder how reliable it might beThanks!

author: fchk
author_rank: Frequent Contributor
timestamp: May 31, 2025, 07:37:38 am
content: I'd use the STLINKV3-MINIE or the STLINKV3-MODS instead. Cheap, faster (USB 2.0 High Speed), and made specifically for integration into own setups.https://www.st.com/en/development-tools/stlink-v3minie.htmlhttps://www.st.com/en/development-tools/stlink-v3mods.htmlThese debuggers cost about 10$ each.

author: dobsonr741
author_rank: Frequent Contributor
timestamp: May 31, 2025, 03:55:59 pm
content: The V3MODS looks nice enough to be MCU dev board with that many exposed GPIO. Has anyone used it that way?

author: incf
author_rank: Frequent Contributor
timestamp: May 31, 2025, 05:15:04 pm
content: No schematic published for the STLINK-V3MODS but according to it's octopart image it appears to use the STM32F732ZE. I suspect the debug pins might not be broken out which might hinder it's usability.

author: langwadt
author_rank: Super Contributor
timestamp: May 31, 2025, 06:36:15 pm
content: Quote from: incf on May 31, 2025, 05:15:04 pmhttps://www.eevblog.com/forum/microcontrollers/st-linkv3/msg2766124/#msg2766124

author: MarkL
author_rank: Unknown
timestamp: May 31, 2025, 10:21:11 pm
content: I've used the Nucleo break-off boards, detached, for development.I cut the ground pins off with a good flush cutter, and covered the bottom of the PCB with two layers of 1" wide Kapton tape.If you look at the whole Nucleo board, there are two other sets of ground pins on the opposite end of the Nucleo board. All four come with jumpers installed on them. They are meant to be feet. With the break-off board detached, they serve no purpose.I use the serial port at 115200 and have never had a problem with data reliability. Unfortunately, the RX/TX header does not have its own ground and instead relies on the ground provided by the SWD header. I always connect both the serial and SWD headers anyway, so it's not an issue.
ST Microelectronics NE555 /SE555 NRND - World coming to an end ?? - Page 1
Forum section: electronics / projects

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: November 06, 2015, 04:24:44 am
content: Hi,This caught my eye:ST has changed the status of the NE555 and the SE555 Timer to NRND, Not Recommended for New Designs.Is the world as we know it coming to an end ??Regards,Jay_Diddy_B

author: crispy_tofu
author_rank: Super Contributor
timestamp: November 06, 2015, 04:30:10 am
content: As long as TI continues selling them...

author: c4757p
author_rank: Super Contributor
timestamp: November 06, 2015, 04:32:38 am
content: Well, the CMOS ones are still active. Makes sense, the bipolar ones blow.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 06, 2015, 09:13:52 am
content: One can only hope!

author: coppice
author_rank: Super Contributor
timestamp: November 06, 2015, 09:35:06 am
content: The 2650, the 8X300 and the 82S100 were killed off, and now this.

author: dom0
author_rank: Super Contributor
timestamp: November 06, 2015, 09:53:11 am
content: Quote from: c4757p on November 06, 2015, 04:32:38 am+1CMOS 555 is a lot better at ... well... everything!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: November 06, 2015, 10:03:57 am
content: Except current output (the current capacity is on par with CD4000 logic, quite weak). Which is a shock for those accustomed to the 100mA drive output of the bipolar version!Tim

author: dom0
author_rank: Super Contributor
timestamp: November 06, 2015, 10:07:42 am
content: That probably depends on which variant you use. I think the TI CMOS 555 (LCM555?) has somewhat weaker output drive, the Intersil 555 is basically the same as the NE.

author: MapleLeaf
author_rank: Contributor
timestamp: November 06, 2015, 02:44:15 pm
content: As long as we have this, who cares !http://shop.evilmadscientist.com/productsmenu/tinykitlist/652-555kit

author: mathias
author_rank: Regular Contributor
timestamp: November 06, 2015, 06:16:22 pm
content: The fact that they (i.e. major semiconductor manufacturers) still make them is quite weird. I don't expect high margins or big profit from this chip.Keeping their bipolar process alive should be quite expensive. Replacing the masks when they wear out, quite expensive as well. But for this feature size, who knows how old the masks are.

author: dom0
author_rank: Super Contributor
timestamp: November 06, 2015, 06:23:17 pm
content: Well maybe they don't make them themselves anymore? Outsourced the job to the companies who bought their old lithography gear?

author: Seekonk
author_rank: Super Contributor
timestamp: November 06, 2015, 06:25:47 pm
content: Quote from: coppice on November 06, 2015, 09:35:06 amI haven't heard anyone mention the 8X300 since the mid 1980's! I think any 555 design should be banned here.
ST motorcontrol workbench IC match - Page 1
Forum section: electronics / projects

author: amirkargar110
author_rank: Contributor
timestamp: September 17, 2018, 06:31:07 am
content: helloI want to use program ST motorcontrol workbench. in this link (with this name in site X-CUBE-MCSDK)https://www.st.com/en/embedded-software/x-cube-mcsdk.htmlmy speed control MCU is STM32F030K6T6 but in the program in MCU select, the nearest MCU to my MCU is the family STM32F030X. in this family in this program just one IC name exist "STM32F030RC" that does not match with my MCU "STM32F030K6T6" because my MCU has 32 pin but "STM32F030RC" has 64 pin.can i use this program with this configuration for my board with MCU STM32F030K6T6 and just change some pin assignments or not?thank you
ST TDA7705 Command/programming reference? - Page 1
Forum section: electronics / projects

author: spilihps
author_rank: Regular Contributor
timestamp: September 25, 2019, 06:10:09 pm
content: Hello!Shopping around for a FM tuner for a project of mine, and ST TDA7705 catched my eye, it seems to have all the functions and quality i want. However, the datasheet does not include any programmers reference and/or any commands for the serial interface.To be able to ask ST about this i need to register, and thats a hassle since im not in a company for this, just a hobbyist.Does anyone know something about this chip, or how you normally get this information on ST products?Thanks!
ST TXAL228BS Triac Datasheet - Page 1
Forum section: electronics / projects

author: paul_g_787
author_rank: Frequent Contributor
timestamp: April 09, 2022, 12:06:13 pm
content: Can anyone point me to somewhere where I can find a datasheet for this triac?ST TXAL228BSI have been through tons of links searching on Google but just get Chinese websites trying to sell me 1,000 of them in bulk.I have a bunch of these Triacs salvaged from old light switch dimmers and I wanted to see if I can use them in a project.

author: moffy
author_rank: Super Contributor
timestamp: April 09, 2022, 02:38:03 pm
content: There is a single line entry at:https://www.datasheetq.com/datasheet-download/894234/1/ETC1/TXAL228B
ST VL53L5CX 8x8 ToF sensor libraries - Page 1
Forum section: electronics / projects

author: davorin
author_rank: Unknown
timestamp: November 29, 2021, 10:20:28 am
content: Good morning (o;Got me some of the VL53L5CX-SATEL evaluation modules.....and tested some simple Arduino apps....Has anyone came across a library where it is possible to do gesture recognition with those sensors?Seen only libraries for Arduino and Python where it outputs some distance matrix.Or is it just a matter of time until those libs pop up as this sensor is rather new?cheersrichard
ST25PE40 SPI 4Mbit EEPROM replacement - Page 1
Forum section: electronics / projects

author: perdrix
author_rank: Frequent Contributor
timestamp: April 04, 2022, 09:59:45 am
content: The subject part has become unavailable as have the AT25PE40 (Adesto aka Dialog) and M25PE40 (Microchip).Replacement should be in SOIC-8N (to avoid a board re-spin), and support low speed SPI (the ARM LPC2388 won't do SPI at 40MHz for example).Obviously replacement can be larger capacity but must be a straight swap (i.e. identical SPI protocol, 3.3V, pinout etc.).To save time fighting through a milliard datasheets has anyone been there, done that and have a recommendation?ThanksDavid

author: Someone
author_rank: Super Contributor
timestamp: April 04, 2022, 10:48:40 am
content: Quote from: perdrix on April 04, 2022, 09:59:45 amWhich chips arent static logic (have minimum clock rates)?I'm seeing such commodity flash chip equivalents stocked in regular channels, from regular brands. Even microchip replacements/equivalents or the equivalents you mentioned! Send money please.
ST70 Barnfind restoration - Page 1
Forum section: electronics / projects

author: jcrubin
author_rank: Frequent Contributor
timestamp: November 22, 2015, 02:09:35 am
content: Here are my videos chronicling the restoration of a dynakit ST70 that sat in an attic over 40 yearsEnjoy,

author: Lightages
author_rank: Unknown
timestamp: November 22, 2015, 02:19:48 am
content: I had an ST70. It was fun to have an old piece of tech that sounded nice. Mine was in very good shape had modern caps. I ran it with a pre-amp that I designed. Now that I see yours, I miss mine
ST7036 Icon Ram - Page 1
Forum section: electronics / projects

author: cdrttn
author_rank: Newbie
timestamp: March 04, 2013, 05:12:11 am
content: I got a EA DOG-M 163 character display with a Sitronix ST7036 chip, which is compatible with the Hitachi HD44780 and has a few extensions. The chip has something called "ICON RAM" but I don't understand how it is mapped to the actual display. Google yields little and the datasheets for the screen and chipset are vague about it. I can write to this ram, but no pixels change on the screen (other features of the screen work fine). Anyone familiar with this?http://www.lcd-module.com/eng/pdf/doma/dog-me.pdfhttp://www.lcd-module.com/eng/pdf/zubehoer/st7036.pdf
ST7735 LCD has  white noise while writing - Page 1
Forum section: electronics / projects

author: Sajeev
author_rank: Contributor
timestamp: August 13, 2025, 11:37:26 am
content: Dear Forum Members,I have this talking clock project which displays time on ST7735 LCD run by ch32v003. the time is read from DS3231 module(aliexpress) and displayed on the st7735(aliexpress_greentab) > i also have a DF MINI mp3 player that announces the time. When i tested the project on a bread board it was running fine and the display didnt have any disturbances . I assembled the same setup on a veroboard (universal prototyping PCB) and found the LCD displays a white hue /noise each time when it updates the seconds. each time update is second wise. The st7735 is powered via 5v and the led backlight is driven by 3v. Seeing this I assembled separate set of similar components directly with wires without a PCB and found the display operates fine without any noise/disturbance. what could be the reason the display having the noise when done on a PCB.Please find attached a small video of the issue.RegardsSajeev

author: Sajeev
author_rank: Contributor
timestamp: August 14, 2025, 03:20:33 pm
content: Hi,I resolved the issue . the ch32v003 is capable on working at 3.3v and 5v. when i tested on breadboard i used 3.3v and when i assembled on pcb i used 5v to run the project. the 5v for ch32v003 was causing the disturbance. i supplied the LCD backlight and ch32v003 3.3v and the rest of the circuit (df player) 5v and the issue disappeared. This aliexpress 180x160 SPI 1.8" TFT unit also had issue with white screen on startup. needs multiple power cycles to start display even with proper reset process. This was resolved by adding a 4.7k pullup to the CS pin of the TFT LCD from 3.3v supply. May be useful for someone who gets stuck.RegardsSajeev
stabilock/wavetek si4015 ref freq - Page 1
Forum section: electronics / projects

author: ME
author_rank: Frequent Contributor
timestamp: August 21, 2025, 05:22:41 pm
content: Does anyone know how i can use my 10MHZ gpsdo as the freq ref on this? , If i remember the manual says it needs some sort of addaptor? that due to its age is made of pure unobtainium!.

author: RFDx
author_rank: Regular Contributor
timestamp: August 22, 2025, 11:41:07 pm
content: The external synchronisation module was optional. It plugs into the back and contains a small PLL with a 74HC4046 that locks the internal 20MHz TCXO to an external 10MHz reference.You could copy the original circuit and make your own module or double the frequency of your reference and use that instead of the internal TCXO.
Stack board connectors - Page 1
Forum section: electronics / projects

author: firstcolle
author_rank: Regular Contributor
timestamp: August 29, 2018, 12:40:32 pm
content: Hi,I'm looking for some connectors that allow me to connect multiple boards together. I have one motherboard with a 100 pin female connector and then multiple and interchangeable child boards with passthrough male/female connector.is there something like that around?thanks
Stacked board - Page 1
Forum section: electronics / projects

author: waulu13
author_rank: Newbie
timestamp: December 21, 2018, 11:21:07 am
content: I am designing a stacked board, something like this,https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=2ahUKEwjP39yW5bDfAhVMThoKHVlvCIkQjRx6BAgBEAU&url=https%3A%2F%2Fwww.datasoft.com%2Fproducts%2Fsidebridgesom%2Findex.html&psig=AOvVaw3Cl1MTiHHdDLgm_G3Rat1e&ust=1545477148962050The top board has these connectors,https://www.hirose.com/product/en/products/DF40/DF40C-80DS-0.4V%2851%29/andhttps://www.hirose.com/product/en/products/DF40/DF40C-50DS-0.4V%2851%29/and I would to place components between the boards but there’s not enough height for that. Can someone recommend solutions please? I thought about designing an adapter just to create height. Maybe and adapter and cables to place it somewhere else. Maybe I can put a small pcb under the connectors to create height. what do you think?Thanks in advance

author: Cloud
author_rank: Regular Contributor
timestamp: December 21, 2018, 11:49:08 am
content: I thing the easiest solution would be to use higher connectors if this is possibility

author: Rerouter
author_rank: Super Contributor
timestamp: December 21, 2018, 12:05:24 pm
content: Hirose do make taller stacked connectors, not to sure on what the series is called but I have found them in VDO gauges, about 22mm board to board when mated.

author: waulu13
author_rank: Newbie
timestamp: December 21, 2018, 12:58:21 pm
content: Thank you for the quick reply.I found these connectorshttps://www.hirose.com/product/en/products/DF40/DF40HB%284.0%29%2D50DS%2D0.4V%2851%29/andhttps://www.hirose.com/product/en/products/DF40/DF40HC%284.0%29%2D50DS%2D0.4V%2851%29/4 mm height is enough for me. Now the problem is that I don't know if I can connect a male with 1.5 mm heighthttps://www.hirose.com/product/en/products/DF40/DF40C%2D50DP%2D0.4V%2851%29/with one of that female connectors.
Stackpole resistors - Page 1
Forum section: electronics / projects

author: Tioleco
author_rank: Contributor
timestamp: August 22, 2013, 08:42:19 pm
content: What is the quality of metal film resistors of Stackpole?Are best than the chinese ebay?They are cheap on Digikey.

author: free_electron
author_rank: Super Contributor
timestamp: August 22, 2013, 09:19:25 pm
content: Stackpole is good. been using em for years. They are an US based manufacturer. Been around since the 1920's ...

author: ampdoctor
author_rank: Frequent Contributor
timestamp: August 23, 2013, 12:54:12 am
content: If you're concerned with any level of quality, I'd stick with the mainstream distributors like digikey, mouser, and so on. I wouldn't buy a thing off of ebay. Too many shady sellers. With regard to stackpole in particular, as far as I know, while the company is US based, everything is all manufactured offshore. So like most components today, odds are everything is made in half a dozen production facilities. Line A goes to Vishay, line B goes to stackpole, etc. Same stuff, just different branding.
Stand Alone IoT device with sensors: any interest? - Page 1
Forum section: electronics / projects

author: DonnieBrodan
author_rank: Contributor
timestamp: August 19, 2024, 01:10:15 am
content: I made a thing:https://standalonecontroller.com/Firmware now open due to challenges in building a viable market to fund certification.

author: DonnieBrodan
author_rank: Contributor
timestamp: September 03, 2024, 10:58:15 am
content: bump if anyone has a youtube channel and would like to do a review
Stand for soldering equipment - Page 1
Forum section: electronics / projects

author: nctnico
author_rank: Super Contributor
timestamp: January 29, 2017, 09:33:08 pm
content: I have been planning to organise my soldering equipment a bit better. Due to limited desk space I needed something to stack the various soldering stations on top of eachother. Now Ersa sells these stands:but I found it a bit too expensive for a piece of metal in a U shape and it is also very narrow. Ideally I'd like to put an Ersa RDS80 and an Atten 858D hot air station next to eachother. Some metalworking seemed unavoidable. However I got a great idea. A while ago I collected a number of old leftover PCBs to throw away. Since FR4 is very sturdy material it would be suitable to build a soldering station stand from. After going through the pile again I decided on using some 3.2mm PCBs which already had the right size and looked somewhat stylish as well. I only had to make two pieces of square brass bar with threaded holes in order to put this together:
"standard charge" Li-ion battery? what does this mean on datasheet - Page 1
Forum section: electronics / projects

author: Dmeads
author_rank: Regular Contributor
timestamp: September 21, 2021, 05:43:54 am
content: Hello all!I am trying to get some info on some Li-ion cells I have.Didnt come with a datasheet(yes, came from good source though, brand new).They are Envision AESC 4th gen cells:https://www.envision-aesc.com/en/product.html- 56.3 Ah- 3.7 VnomEnvision hasn't emailed me back, but these same cells are also used in the 2018 nissan leaf car, and some sellers on Alibaba have datasheets for those modules,so I found one, and he gave me part of a datasheet for his product (just had to do a little calculation because his has 2p cell config whereas I just have 1 cell).It clearly states the discharge rate of 0.3C, as well as max and min voltage, all are the values I expected, but for charging, it says "standard charge"I have the emailed the alibaba guy back and asked for the whole datasheet, but in the mean time, anyone know about this?I found this quote: "the IEC (International Electrotechnical Commission) standard of lithium battery DISCHARGE rate is 1C"Maybe this means standard charge is 1C?attatched is a pic of the single page of the datasheet I was sent.Anyway, I was just wondering while I wait for an email back.Thanks for lookin!

author: amyk
author_rank: Super Contributor
timestamp: September 21, 2021, 06:10:29 am
content: Ask the seller for the page of the datasheet with the notes on it, and refer to note 3.

author: Daixiwen
author_rank: Frequent Contributor
timestamp: September 21, 2021, 07:49:03 am
content: I don't think there is a standard definition of "standard charge". But typically the recommended charge rate is lower than the discharge rate. So if they specify their cells for a discharge at 0.3C, I wouldn't charge them at a higher rate than that.For cells like 18650 a typical cycling test could use 1C for discharge and 1/2C for charge.

author: mikerj
author_rank: Super Contributor
timestamp: September 21, 2021, 09:06:41 am
content: The "standard charge" references note 3, what does this note say?
standard fluidic circuit kit? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: November 11, 2023, 08:57:37 pm
content: So I feel like 3d printers have gone nowhere with fluidics. Not sure where they were supposed to go.I thought about a standard set of parts to use. Say focused on a particular tubing, like 1/16 of an inch.Then you could have a E-series of restrictions and couplers. Then at least you could build resistive circuits.Has anyone seen a kit like this so you can print basically one of those old electronics learning kits ? Its a mess with a bunch of ASIC like circuits if you search for it. I imagined like a master kit of devices for some specific tubing size.

author: tggzzz
author_rank: Super Contributor
timestamp: November 11, 2023, 09:10:16 pm
content: Logic gates up to flip flops complexity are known, but the ones I saw used 2000-4000psiMight be possible to 3D print such circuits in brass, but not PLA!

author: coppercone2
author_rank: Super Contributor
timestamp: November 11, 2023, 09:17:09 pm
content: I see some vortex amplifier on thingiverse, but the thing is... there is no like standard for any of these things. Random tubing random connections etc. I almost feel like you could have AI design a series of basic fluidic parts.https://www.thingiverse.com/thing:15676That looks like a low pressure device. But even hooking it up and biasing it, networking them, measuring them, etc...if you have something that runs on silicone tubing, it seems reasonable to build all the accessories for it to make whatever circuit within say a decade or two.IDK where you could get if you are able to make a resistive divider with 3 decades of values in silicone tubing. Maybe somewhere?

author: tggzzz
author_rank: Super Contributor
timestamp: November 11, 2023, 09:34:36 pm
content: ISTR "microfluidics" being a topic a few years ago. That might be a useful search term.

author: coppercone2
author_rank: Super Contributor
timestamp: November 11, 2023, 09:52:18 pm
content: most of that is on chip stuff. I guess this would still be useful for like... the input connections.Thats where the mess begins. Tons of technologies, all unique demonstrators, no real circuit kit... kind of like custom ASICI thought like small objects you can print and breadboard...those thingiverse prints are interesting because its plastic you can print out and connect to a hose! not mess around with shrink film, exotic polymers, etcfor instance, with a pump and restrictions, you could make the basic non ideal current source like a V+R circuit. If you had alot of restrictions, then you are at least close to being able to light up a fluidic equivalent of a bulb with a random pump source. Or possibly setup a voltage divider, or current divider. Its basic but that used to be hot in the 1800's lol, a advanced electronics lab had a bunch of resistors.
Standard power supply voltage  - Page 1
Forum section: electronics / projects

author: 001
author_rank: Super Contributor
timestamp: October 24, 2017, 03:56:57 am
content: We know that common USB charger voltage is not 5.00000 volts but 5.1-5.3 to compensate wire lossAnd automotive radio PS marked '12V' in fact about 13.8V for same reasonWhat about 'real' voltage for 3.3/9/15/24 volts power supply?

author: mariush
author_rank: Super Contributor
timestamp: October 24, 2017, 04:04:16 am
content: No, we don't "know".Some usb chargers have sense wire all the way to connector so that output will be 5v no matter the loadOthers will just use a 5.6v zener diode as voltage referenceCar stuff is more like "whatever battery or alternator gives" with additional allowances for spikes or reverse voltage periods ... auto power is just ugly.if you mean atx power suply voltages they're standardized , just read the atx specification, it's available on the net a site with "form factors" or something like that in name has it

author: frog
author_rank: Contributor
timestamp: October 24, 2017, 04:09:26 am
content: In general, power supplies should output pretty much exactly the voltage that they claim; in reality there will always be a tolerance, typically 5% or better and you'll see this in the datasheet for the device. On high-current supplies you'll sometimes see 'sense' inputs; the purpose of these is that they can be connected to the point of load so the supply can adjust the output to make sure the load sees exactly the right voltage.Incidentally, vehicle electrics are 13.8 because that's the normal charging voltage a 6-cell lead-acid battery. The idea that it's 2v per cell (12v total) is an approximation and depends on the load and state of charge (etc). You may see bench supplies designed to drive automotive equipment such as radio transceivers that specify a 13.8v output.
Standard ribbon cable vs custom flat flex cable - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: October 12, 2016, 04:02:35 am
content: At what point do flat flex cables start becoming necessary? Are ribbon cables typically fine until you hit a couple hundred MHz, or is the effect noticed at a much lesser frequencies around 40 MHz?

author: jbb
author_rank: Super Contributor
timestamp: October 13, 2016, 11:01:03 pm
content: HiI'm not sure about frequency limits per se. You can jam quite a lot of data down a ribbon cable - probably over 40 MHz.It's a question of signal integrity and interference. Let's think about a 40 pin cable.If you try to use 39 high-speed CMOS signals and 1 ground, it will fail.If you use 20 high-speed CMOS signals and 20 grounds (SIG, GND, SIG, GND...) it might work, but will radiate noise. You will probably also need termination resistors to prevent (big!) ringing.If you use LVDS, you will need to use 2 pins per signal. But because the signal is differential it will radiate much less noise, and be less susceptible to noise from elsewhere. LVDS also requires termination resistors. You can lay out a cable like GND, D+, D-, GND, D+, D- .... to yield 13 pairs and 14 grounds. It might go up as high as 500 MHz (depending on length).Also note that the behaviour of CMOS signals depends not just on the fundamental frequency, but also the sharpness of the edges. A 1kHz signal with a super-fast edge could cause more interference than a 1MHz signal with gentle edges.Hope that helps

author: JS
author_rank: Frequent Contributor
timestamp: October 13, 2016, 11:29:04 pm
content: Quote from: jbb on October 13, 2016, 11:01:03 pmFun fact, yesterday I was reading a MAX485 datasheet and they call them slew-rate-limited transcivers.JS
Star grounding with a darlington-pair - Page 1
Forum section: electronics / projects

author: matseng
author_rank: Frequent Contributor
timestamp: June 18, 2015, 10:42:42 am
content: Well, this is not a fully star, but rather separate grounds for the power transistor with open collector output to drive a motor and the rest of the logic. The ground wires will end up wired together further down closer to the powersupply.My question here is if the T2 should belong to the digital ground (GND) or the "power ground" AGND? I'm leaning towards the digital ground, but I just wanted to check with someone of better knowledge. :-)Will the darlington be screwed up royally if the collectors are not connected by a low impedance/resistance path?( And yes - the transistors really should be Q's not T's)

author: dom0
author_rank: Super Contributor
timestamp: June 18, 2015, 10:55:31 am
content: That's not even a darlington, and I can't see how it should work. T2 could only shunt current from T1's base, but nothing (except leakage) will supply base current to T1.Remember: Darlington means collectors paralleled, emitter-to-next-base. Also, for low-voltage switching darlingtons are bad due to their high saturation voltage.

author: matseng
author_rank: Frequent Contributor
timestamp: June 18, 2015, 11:02:44 am
content: Eh yes......You are completely right - that is not a darlington - I hang my head in shame and blame the pain meds I'm currently taking.Disregard the question.
Starling: A modular Internet connected Wifi Display - Page 1
Forum section: electronics / projects

author: Sandeep@ExploreEmbedded
author_rank: Newbie
timestamp: December 01, 2015, 05:15:21 am
content: Hi Everyone,Please checkout the first demo of Starling. Let me know what do you think about it.The project details on wiki page:http://exploreembedded.com/wiki/Starling:_A_simple_internet_connected_modular_led_display.

author: DanielS
author_rank: Frequent Contributor
timestamp: December 01, 2015, 12:45:43 pm
content: Quote from: cleaningOut on December 01, 2015, 08:18:40 amThe display is perfectly fine as a modular unit: daisy-chain however many units you want to have whatever length you need, then bolt them on a piece of plexiglass or something else of the sort for structural support.Nearly every large LED/lamp-based wall display is built on the principle of NxN tiles daisy-chained together or grouped into macro-tiles to enable the manufacturer to produce arbitrarily sized and shaped displays using mostly common stock tiles.

author: Sandeep@ExploreEmbedded
author_rank: Newbie
timestamp: February 09, 2016, 10:31:39 am
content: Thanks for the suggestions!We plan to make a plastic molded case after the campaign.Starling is live on Crowd Supply, do back us and help us get starling to lifehttps://www.crowdsupply.com/explore-embedded/starling
Start your PC with your phone! - Page 1
Forum section: electronics / projects

author: MathCa
author_rank: Contributor
timestamp: March 07, 2023, 10:36:04 pm
content: You'll need a simple ESP32 or ESP8266, at least 2 jumper wires and a USB cable for the ESP.1. Find thepower switchconnectors on your motherboard. If you need to find the manual of your motherboard, you need to know the model! On Windows, Win+R,msinfo32, and look at the value ofBaseBord Product.Find the Power Switch.jpg

author: Benta
author_rank: Super Contributor
timestamp: March 07, 2023, 10:58:30 pm
content: Seems to be a solution looking for a problem...

author: shapirus
author_rank: Super Contributor
timestamp: March 07, 2023, 11:06:19 pm
content: https://en.wikipedia.org/wiki/Wake-on-LAN

author: pardo-bsso
author_rank: Frequent Contributor
timestamp: March 08, 2023, 03:54:57 pm
content: Quote from: Benta on March 07, 2023, 10:58:30 pmI configured the BIOS to start when the AC power comes and then a dumb sonoff clone with tasmota does the rest.

author: MathCa
author_rank: Contributor
timestamp: March 08, 2023, 04:27:55 pm
content: Quote from: Benta on March 07, 2023, 10:58:30 pmLol it's the basic idea to make a first prototype. Then you should add an optocoupler, a small case for the ESP, get power from the ATX 24 pins cable (purple wire = +5v always on), etc. 😉But you have to be able to open your pc else yes you could create a lot of problems 😅

author: MathCa
author_rank: Contributor
timestamp: March 08, 2023, 04:43:54 pm
content: Quote from: shapirus on March 07, 2023, 11:06:19 pmIt's definitely a better solution for most! It's also possible by Wi-Fi for those with laptops!I'm also using the ESP to communicate with a process running in background to do more things like put the computer on sleep when nothing important is running, close the screen, mute the sound, it can also display on the app the state of the PC, lock it when I'm away (disconnected from Wi-Fi), etc. I also love to play with small radar sensors, and it's easy to make them work wirelessly together.It's 99% for fun 😉 We don'tneedsomething similar hopefully.
Starting and stopping a motor once per minute vs leaving on continuously. - Page 1
Forum section: electronics / projects

author: wmdunn
author_rank: Newbie
timestamp: December 13, 2023, 06:33:38 pm
content: My current project consists of a 12V DC air pump motor with a permanent magnet that I need to function for long period of time; on the order of weeks at a time without turning the device off. Currently, this motor turns on for 2-3 seconds per minute and seems to be doing fine for days at a time. Is this worse for the motor than leaving it on continuously? It drives a pneumatic system so I could have it feeding a pressure reservoir, however this would greatly increase the complexity and cost of the project. What do you guys think? Thanks!

author: bdunham7
author_rank: Super Contributor
timestamp: December 13, 2023, 06:44:18 pm
content: It's most likely fine as-is IMO. Those motors really aren't meant for continuous duty and the start/stop probably reduces wear and thermal issues. Does the system require the compressor to reach anywhere near its maximum pressure or is it operating at a lower pressure?

author: liaifat85
author_rank: Regular Contributor
timestamp: December 14, 2023, 12:24:31 pm
content: Running the motor intermittently can reduce wear and extend its lifespan compared to continuous operation.

author: wmdunn
author_rank: Newbie
timestamp: December 14, 2023, 10:00:50 pm
content: I talked to the manufacturer and they said that it was continuous duty and that it would probably be fine to have it starting and stopping. Thanks for the second opinion! Everything helps.

author: wmdunn
author_rank: Newbie
timestamp: December 14, 2023, 10:02:23 pm
content: Also, it usually is outputting its standard PSI as it has been run at 12 V with a PWM.

author: hbozyq
author_rank: Contributor
timestamp: December 17, 2023, 06:58:35 am
content: For brushless motors it would be fine. Might be a bit of a problem for brush motors, for the high current at start-up may ablate the brush.

author: Terry Bites
author_rank: Super Contributor
timestamp: December 17, 2023, 12:10:59 pm
content: I'd slow start it to minimise stress on the moving parts.
starting point temp. for soldering power supply caps. 10k 80v. electrolytics - Page 1
Forum section: electronics / projects

author: p5200
author_rank: Contributor
timestamp: February 05, 2015, 01:55:56 am
content: I have a Hakko FX 888D Soldering station but, am used to using the cheap 30-40 watt irons from Radioshack. I'd appreciate some advice on about what temp. I should try to solder these new higher quality caps in the board. I'm not sure what type board it is but it's in a Parasound Halo A23 2 channel power amp 125 wpc.x 2 into 8 ohms. These are the caps and the lead descriptionhttp://www.soniccraft.com/product_info.php/mundorf-mlytic-ag-mlgo-10000uf-80vdc-p-4088Thanks!

author: mariush
author_rank: Super Contributor
timestamp: February 05, 2015, 02:06:44 am
content: Somewhere between 300c and 350c should do it. The larger the copper traces, you would need to increase the temperature a bit.Leaded solder melts at around 180c, lead free solder melts at around 210-220c, so your soldering iron tip needs to be above these temperatures, but when you put the iron tip on the copper or touch the leads, these will pull heat away from the tip. Larger the copper traces basically act like a heatsink for the iron tip. So you need to get the temperature at some point where, when you put the iron tip down, the temperature will drop a bit but still be above that melting temperature.

author: p5200
author_rank: Contributor
timestamp: February 05, 2015, 02:40:44 am
content: Thanks very much for the info I'll be sure follow your advice!
State of the art switching frequencies vs voltage - Page 1
Forum section: electronics / projects

author: PartialDischarge
author_rank: Super Contributor
timestamp: March 26, 2021, 06:04:46 am
content: What would you say in your experience are the current maximum (more or less) practical (not the futuristic research) switching frequencies vs voltages for lets say 600V to 2500V ?For Sic mosfet, gan, igbt...

author: jonpaul
author_rank: Super Contributor
timestamp: March 26, 2021, 09:56:14 am
content: Bonjour: The design of a SMPS involves many choices, converter topology, magnetics, regulatory compliance, cost and availability of critical parts.The migration from hard switching to soft switching and resonant converters has greatly reduced switching losses and opend th way to frequenchs increasing each decade, eg 1950s 5-15 kHz, 1960s 20 kHz 1980s 100 kHz 1990s 1 MHz, nowadays 1-100 MHz.However Impossible to respond without specific information:Input/output voltages, currents, min/max power?Application area, environment?Regulatory compliance?for production or one time proto?See the IEEE Power Electronics and Industrial Electronics proceedings, and the many excellent conference papers from PELS, PESC, etc. for latest developments.Bon Chance,Jon

author: PartialDischarge
author_rank: Super Contributor
timestamp: March 26, 2021, 10:07:27 am
content: Thanks jonpaul,I'm just trying to gather "points", like a someone has a converter running at 600V and 500kHz 100W with SiC technology, or 1500V for solar at 100kHz.... etc...

author: Wolfram
author_rank: Frequent Contributor
timestamp: March 26, 2021, 10:33:45 am
content: For superjunction MOSFETs at 400 V DC bus, switching frequencies tend to be in the 50 - 100 kHz range for hard-switched topologies, and 100 - 800 kHz for soft switched topologies in the multikilowatt range. SiC allows you to double the DC bus voltage and increase the power level to a few tens of kilowatts, at the same switching frequencies. These are not the extremes of what's possible, more like real-world values from balanced designs. There's a lot of freedom in the choice of switching frequency, depending on target efficiency, power density and cost.Beyond a megahertz or two, transformers power density stops increasing with frequency, due to limitations of available magnetic materials and manufacturable litz. Converters above these frequencies are mostly of interest when you need to operate at high frequencies for reasons other than power density.
State Variable Filter, looking for advice - Page 1
Forum section: electronics / projects

author: dejv
author_rank: Newbie
timestamp: July 06, 2021, 09:01:08 pm
content: Hi guys,I'm currently working on a design for a notch filter to be used for audio/hifi. It's built from a state variable filter, where the band pass signal is summed with the buffered input signal. The schematic is attached below. I haven't done much theory on filters, this is drawn using some proven designs as reference, and a prototype is working great. But there is two drawbacks:1. The output is invertingNot a huge issue, since i'm cascoding two of these circuits at the moment, but it would be a bit more elegant if I were able to bypass one of the circuits/notches without inverting the phase. Can I just change to a non inverting summing amplifier, without any impact on the filter circuit and its performance?Like thisIf so, I could perhaps use the same summing amplifier for a second SVF, instead of cascading two complete circuits to get two notches. Am I right?2. The frequency pot behaviour is far from linearIn the prototype, I'm tuning the integrators using a dual gang anti-log pot, but the frequency sweep is very "touchy" making it hard to adjust. After some reading, I've tried to simulate the adjustment range with the pots connected as voltage dividers to ground instead of rheostats. See the alternative schematic.With a linear pot, I get pretty nice results. I can also reduce the value (and part size) of C2 & C3 from 1 µF to 330 nF, which is a nice bonus. The resistive load for the driving OP-amp is 5-6 k, which OPA1644 should drive without any excessive distortion. It's also a lot easier to source a suitable potentiometer. Am I missing something here? Will this hurt noise or distortion performance?Simulations posted are for the alternative schematic at 0%-33%-67%-100% turn.Any advise is greatly appreciated!

author: Benta
author_rank: Super Contributor
timestamp: July 06, 2021, 09:47:40 pm
content: Perhaps I'm dense, but I see no difference between the two schematics.

author: dejv
author_rank: Newbie
timestamp: July 06, 2021, 09:51:32 pm
content: You're right! Sorry for that, I've updated the attachments.
State variable filter, the digital implementation - Page 1
Forum section: electronics / projects

author: Yansi
author_rank: Super Contributor
timestamp: May 04, 2019, 04:12:34 pm
content: Hello,supposed I have to implement this, the State Variable Filter:What I do not understand clearly, is whether I have to implement this exactly to get the desired behavior, or whether I can toy a bit with the integrators to make implementation somewhat more efficient.What I mean is this: There are two forms of the digital integrator. The implementation of SVF above uses both types. The Question is, whether I could for example replace the second integrator with the other form. Will it still work as intended?The same I could ask with regards to the bandpass output: Could I obtain the output just after the z-1delay block? (The signal will be obviously the same, but 1 sample time delayed).That would for example make for a nice optimization using a MAC instruction on a real microprocessor, as I could implement this whole block as a single MAC this way:Code:y = y[n-1] + Fc*xAnd same for the other integrator, the Lowpass output respectively.
Extreme Brutal and Simply Bench Power Supply Project  /Statron/ - Page 1
Forum section: electronics / projects

author: 001
author_rank: Super Contributor
timestamp: November 19, 2018, 02:16:03 pm
content: Hi!Very detalised project herehttps://www-user.tu-chemnitz.de/~heha/basteln/Konsumg%C3%BCter/Statron/Any opinions?

author: Wolfgang
author_rank: Super Contributor
timestamp: November 21, 2018, 12:54:13 am
content: This is how I made my first power supplies some decades ago. Stability was everything, ensured by a "fat" output capacitor creating a dominant loop pole so low that any other time constants had no choice to make it unstable.A side effect was a sort of "electronic Widlarization", especially for the higher voltage versions. If a test circuit misbehaved and decided to go low-ohmic for whatever reason, the output cap would just dump a few or even a few ten Joules into it, causing the culprit to enter the eternal electronic hunting grounds immediately. Smaller circuit would even evaporate leaving a clueless operator behind. Happened once with a 400V supply.

author: 001
author_rank: Super Contributor
timestamp: November 21, 2018, 08:08:44 am
content: Quote from: Wolfgang on November 21, 2018, 12:54:13 amGreat answer!But sorry for my english. What "electronic hunting" means?You say "cap would just dump a few or even a few ten Joules into it"No way to limit current isnt`it?

author: MK14
author_rank: Super Contributor
timestamp: November 21, 2018, 08:22:49 am
content: Quote from: 001 on November 21, 2018, 08:08:44 amThey (seem to) mean that the component is killed/destroyed, damaged beyond further use.Analogous to hunting/killing animals in a hunting ground.By the excessive current/energy.

author: mfro
author_rank: Regular Contributor
timestamp: November 21, 2018, 08:44:58 am
content: Quote from: MK14 on November 21, 2018, 08:22:49 amA German phrase that probably does not translate well if you did not read Karl May's Winnetou as a child. When native Indians died there, they went to the "happy hunting grounds".

author: 2N3055
author_rank: Super Contributor
timestamp: November 21, 2018, 09:37:56 am
content: Quote from: mfro on November 21, 2018, 08:44:58 amLOL Winnetou.... Man, that was long time ago....!!

author: Wolfgang
author_rank: Super Contributor
timestamp: November 21, 2018, 12:58:07 pm
content: Quote from: 001 on November 21, 2018, 08:08:44 am