hybridfree/eevblog-posts huggingface dataset:
300v buck step down converter for ripple reject for 400W SMPS, any ideas? - Page 1
Forum section: electronics / projects

author: Kokoriantz
author_rank: Frequent Contributor
timestamp: October 09, 2024, 08:48:15 am
content: I want to create an open source universal circuit to feed the SMPS with clean DC. I tried one on simulator that works but at 2khz only, resulting 60A currents. I tried to find a high voltage controler, I could find only scooter chargers that are 30 times slower.The frequency in my circuit is variable only by the inductor and decreasing it, increases also the peak current.Any solution or proposition for a controler?

author: jonpaul
author_rank: Super Contributor
timestamp: October 09, 2024, 09:27:01 am
content: use a PFC, provies harmonic compliance, universal input 90..250VBus will be filtered 360VDC.Jon

author: Kokoriantz
author_rank: Frequent Contributor
timestamp: October 09, 2024, 12:05:51 pm
content: Thank you for the suggestion.Such thing does exist ready-made, I want to offer a much cheaper to match $20 SMPS used nowadays in Audio.I found a low cost chip, MP9488, it can 40khz, I will try to add a MOSFET or IGBT.

author: jonpaul
author_rank: Super Contributor
timestamp: October 09, 2024, 01:53:55 pm
content: Easy to add PFC correction, many chips and off the shelf indrs exist.See TI.com.At 20W an ordinary power FET is fineNo need for IGBT.j

author: Kokoriantz
author_rank: Frequent Contributor
timestamp: October 09, 2024, 11:53:30 pm
content: The problem with TI controlers, they need a low power supply. The bellow circuit is a TI power supply sold for class D audio amp.The MP9488 can also do it at low power, all I need is to adapt a more powerful mosfet.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 10, 2024, 02:17:16 am
content: The high peak to average ratio of most audio content would make power factor correction difficult to achieve and mostly meaningless.
300VDC on-off switch for piezobuzzer stack solenoid - Page 1
Forum section: electronics / projects

author: dusta
author_rank: Newbie
timestamp: May 03, 2018, 09:13:35 am
content: Hi,I have made a stack of 20mm piezo buzzers move a push rod 1mm. I have made a 300vdc supply from a 555 timer boost circuit that seems to work.Currently I have a N channel Mosfet switch with a resistor in parallel to the piezo stack to discharge it when the switch is off.How can I get rid of the resistor (maybe replace it with a three way switch)? Or how else could I charge and discharge the Peizo stack using a better method?I only need the piezobuzzer stack solenoid to operate at 5-15hz on-offThanks

author: Zero999
author_rank: Super Contributor
timestamp: May 03, 2018, 12:40:17 pm
content: That depends on the short circuit current of the boost converter and the amount of power the MOSFET can dissipate.It's certainly not the most efficient solution, which would be to use a push-pull output stage.

author: dusta
author_rank: Newbie
timestamp: May 03, 2018, 07:31:52 pm
content: Would a UCC27710 (620V, 0.5-A, 1.0-A High-Side Low-Side Gate Driver With Interlock) do the trick or is there a easier to get cheaper option considering that it doesn't need to switch that fast (10Hz)?

author: Zero999
author_rank: Super Contributor
timestamp: May 05, 2018, 05:30:32 pm
content: Quote from: dusta on May 03, 2018, 07:31:52 pmThat IC won't do what you want on its own. It require a couple of MOSFETS and the bootstrap capacitors will have to be very large for such a low frequency.

author: Twoflower
author_rank: Frequent Contributor
timestamp: May 05, 2018, 07:24:38 pm
content: A bit of off-topic. But have a think or two on protecting the circuit from the reverse piezo effect. What happens to your circuit if something hit the stack...

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 05, 2018, 11:07:44 pm
content: Quite interesting you managed to make your own piezo actuator that can move 1mm. Could be the start of a piezoelectric expansion valve for DIY refrigeration and HVAC, an area of improvement that has, to my knowledge, never been explored by any hobbyist. Could be particularly interesting when the outdoor temperature is just slightly too high for simple ventilation to be effective and the theoretical maximum efficiency of a heat pump with a low delta T is very high.My suggestion would be to gate the DC/DC on and off with a high voltage MOSFET switching in a parallel resistor to discharge the actuator faster than the feedback divider does.
30v 1A supply design feedback - Page 1
Forum section: electronics / projects

author: xReM1x
author_rank: Regular Contributor
timestamp: November 13, 2015, 08:43:08 pm
content: I'm building a power supply based around mark III design.yes I'm using PNP transistor, please dont mention it begin PNP and not NPN.here is the schematics with some notes + attached download to play around.I'm hobbyist so I would like some feedback about things to change (expect using darlington npn configuration).also D5 and D4 will be 3A big diode, and 2A fuse.

author: Kleinstein
author_rank: Super Contributor
timestamp: November 13, 2015, 09:10:39 pm
content: This design looks problematic at several spots:1) the oudput stage has quite some voltage gain. So even with the rather slow LT1013 stability can get tricky. ESR 7 ESL of the output capacitor can cause trouble if build in real life.2) The PNP output stage likely has poor PSRR - so quite some of the ripple of the preregulator can apear at the output.Even with a good linear stage, a passive filter between preregulator and linear stage is usually a good idea.3) The preregulator may not give enough headroom for the output stage - looks like a close call, might work, or not at higher currents. This is easy to fix (slight change in R4).4) Current sensing is rather poor: the OP does not have enough supply voltage. Sensitive to exact resistor match and CMRR of the OP, rather slow possibly instable in current configuration. Here I would consider moving the shunt to the low side,a s the shunt at the high side is the root problem.

author: xReM1x
author_rank: Regular Contributor
timestamp: November 13, 2015, 09:21:06 pm
content: Quote from: Kleinstein on November 13, 2015, 09:10:39 pmthanks for the quick reply!1. I'm going to use LM358 or OP275 or any common op amp (probably LM358 as it is close to the LT1013). what can I do to get it more stable?2. so adding other stage to the pre regulator out, for example other LC filter and play with it? will it be good solution? I'm aware of the low PSRR.3. didnt have any problems with headroom voltage, but I will have other look at it. thanks for noticing.4.for current sensing like I said I'm going to use the MAX472. (link:https://www.maximintegrated.com/en/products/analog/amplifiers/MAX472.html).

author: dom0
author_rank: Super Contributor
timestamp: November 13, 2015, 09:25:00 pm
content: Didn't you already create like three threads for this design?https://www.eevblog.com/forum/projects/lab-power-supply-design/https://www.eevblog.com/forum/projects/a-dropout-issue-with-mark-iii-psu-design/https://www.eevblog.com/forum/projects/almost-finished-lab-psu-schematic-(based-on-mark-iii)/

author: xReM1x
author_rank: Regular Contributor
timestamp: November 13, 2015, 09:28:49 pm
content: Quote from: dom0 on November 13, 2015, 09:25:00 pmyes, but im always changing the design and fixing things, thats why I open a new thread most of the time.
-30V Supply for diode - Page 1
Forum section: electronics / projects

author: slowertech
author_rank: Contributor
timestamp: May 16, 2017, 04:19:06 pm
content: Hi,I need to create a -30V voltage rail for a diode I want to use but I am having trouble creating that.I have attached a schematic for something I had put together but I do not seem to be able to get it to output what I need, I am actually getting ~3V.I had used the formula within the datasheet to figure out the value for R4 that I would need to get -30V.Maybe someone will see something obvious that I have glossed over or has an alternative part I could try?The part I am using is an LT1372HVCS8#PBF and the datasheethttp://cds.linear.com/docs/en/datasheet/13727fbs.pdfThanks!

author: Zero999
author_rank: Super Contributor
timestamp: May 16, 2017, 05:03:09 pm
content: Quote from: slowertech on May 16, 2017, 04:19:06 pmThat seems like an unusual thing to do.What sort of diode is it?Please post a schematic of what you're trying to power. It's possible there's an easier way to do this.

author: slowertech
author_rank: Contributor
timestamp: May 16, 2017, 10:36:41 pm
content: I have attached a schematic with how the circuit is set up.The part is a Silicon Photomultiplier from SensL.The part I am using is ArrayJ-60035?4P-EVBhttp://sensl.com/estore/arrayj-60035-4p-evb/The documentation for the parthttp://sensl.com/products/j-series/

author: daveshah
author_rank: Unknown
timestamp: May 17, 2017, 08:40:12 am
content: This was my SiPM bias circuit, if you're curiousSee the full writeup here:https://ds0.me/sipm/index.html

author: capt bullshot
author_rank: Super Contributor
timestamp: May 17, 2017, 11:38:48 am
content: Does it work if you swap the output pins of the transformer?The polarity isn't indicated in your diagram, must be correct for the circuit to work

author: slowertech
author_rank: Contributor
timestamp: May 17, 2017, 02:15:39 pm
content: daveshah,Thanks that is awesome! I will actually look through that later today when I have down time later today.capt bullshot,I was looking at it early this morning and noticed I completely messed up the pin positions for the transformer, also noticed I did not have the part number in the schematic. Sorry about that.The transformer is part: CLS62NP-100NCI will correct it today and poke around with it a bit and update.Thanks!
30W Buck LED driver.....pulse transformer or isolated DC supply to drive NFET? - Page 1
Forum section: electronics / projects

author: ocset
author_rank: Super Contributor
timestamp: November 26, 2017, 12:24:19 pm
content: Hello,We are designing a 30W Buck LED driver, Vin = 400V, VLED = 260V.We are using a Buck converter with a high-side NFET. (as in the attached schematic and also the LTspice simulation.)Rather than use a gate drive transformer to drive the high side NFET, we are going to use an NXJ1S1212MC isolated DCDC power module to provide a high-side bias supply, from which the high side NFET can be driven (via a digital isolator).NXJ1S1212MC isolated DCDC power module (vin=12v, vout = 12v)http://www.farnell.com/datasheets/2282933.pdf?_ga=2.9397109.1106301863.1511695680-287702491.1506211291…the only reason for doing this, ..is because we are already using the NXJ1S1212MC isolated DCDC power module in another one of our products (for a completely different application).The problem will come if this DCDC module goes obsolete. There are others available, but none have the advantageously low isolation capacitance that the NXJ1S1212MC has.What do you think are the chances of the NXJ1S1212MC going obsolete in the next 5 years?
32 keys encoder with 74922 - Page 1
Forum section: electronics / projects

author: EP3SK
author_rank: Newbie
timestamp: October 23, 2019, 02:57:46 pm
content: i am trying to make a 32 keys encoder using 74922 . as it was mentioned on datasheet i am trying to test it with Proteus. 16 keys circuit works fine but i am wondering how to connect 32 keys as on datasheet the connection between two key pads are not clear. please advise .

author: picburner
author_rank: Frequent Contributor
timestamp: October 23, 2019, 03:39:12 pm
content: Perhaps designed like this is clearer.In practice the X lines continue up to the other buttons (16-31) and the additional data line D4 is obtained through the 74C20.

author: EP3SK
author_rank: Newbie
timestamp: October 23, 2019, 03:40:48 pm
content: thanks . this has been tried . not functioning.
32:1 low cost mux switch? - Page 1
Forum section: electronics / projects

author: tozitom
author_rank: Contributor
timestamp: July 20, 2020, 09:04:07 am
content: hi forum,I've designed a "keyboard sniffer/simulator" with 16 channels input/output - basic working is: a uC receives signals from 16 channels input (keyboard or other), and replicates them via 2x16 channels mux (4067d) - it also comunicates with other board in between via RX/TX bus...example: if I have COL1 and ROW1 connected on input, I replicate it on output by controlling both mux"ABCD" inputs.Anyway, I need to do the same but with 32 channels now... and using 32:1 mux seems not to be an option due to high cost of such components (ex = ADG732)! I planned to duplicate the 2x16 channels configuration and control the setup with the uC (ABCD + ENABLE) but wonder if there's out there some 4067D equivalent with 32 channels, or any other simple way to do the job...Thanks for looking.

author: capt bullshot
author_rank: Super Contributor
timestamp: July 20, 2020, 09:35:39 am
content: I'd use four 4051 type muxes tied together to a 32:1 mux, using the enable pins. Most probably this is smaller and cheaper than a dual 4067 type.

author: NiHaoMike
author_rank: Super Contributor
timestamp: July 20, 2020, 01:38:51 pm
content: Also take a look at cheap microcontrollers and FPGAs.

author: Scrts
author_rank: Frequent Contributor
timestamp: July 20, 2020, 04:37:03 pm
content: Quote from: NiHaoMike on July 20, 2020, 01:38:51 pmThis.Long time ago I did a mux with Xilinx 9536 CPLD, when other options were not available.

author: Kleinstein
author_rank: Super Contributor
timestamp: July 20, 2020, 05:55:20 pm
content: i would consider 4051 (8:1) and using 4 pins from the µC. One does not even need to used the enable pins.

author: tozitom
author_rank: Contributor
timestamp: July 22, 2020, 08:51:02 am
content: thanks all for your suggestions.Another point to limit the options is I need it to be "voltage flexible". it will work with different kind of voltages on the "keyboard simulator" side, so the cheap uC/CPLD are not an option I think...The 40xx has the advantage to work up to 18v on Texas version.Will compare both options: (2x4067) vs (4x4051).Thanks again.
33µA constant current / 3.3V max source ? - Page 1
Forum section: electronics / projects

author: Otatiaro
author_rank: Regular Contributor
timestamp: December 02, 2012, 12:57:24 pm
content: Hello,What would be the best option to make a reliable, about 33µA (a bit higher, like 50µA, would be ok too) constant current source under max 3.3V, using small SMT components ?Thomas.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 02, 2012, 07:05:59 pm
content: An opamp current source. Google for it and you will find many examples.There are other possibilities if you need special requirements, but this should get you started.Even simpler would be a self-biased JFET current source.

author: PA0PBZ
author_rank: Super Contributor
timestamp: December 02, 2012, 09:06:14 pm
content: This worked for me as a simple current source:Code:+-------+----+| |.-. |1K | | || | |'-' || |/|--| NPN| |>D V |- || .-.| | |D V | |18K- '-'| |+-------+----+

author: DaveW
author_rank: Frequent Contributor
timestamp: December 03, 2012, 01:09:30 pm
content: It's worth having a look at something like this as well if you need constant current over a wide range of loads. Make sure the op-amp has a low-ish input bias current though
Switching Regulator Max Output Current for 34063U? - Page 1
Forum section: electronics / projects

author: hal9001
author_rank: Regular Contributor
timestamp: September 30, 2021, 08:49:03 am
content: The 34063U regulator has 1.5 A output switch and can buck, boost and invert.But the examples from the data sheet show different max output currents per each mode and not too much explanation how to increase max current since it has a 1.5 A switch inside.The voltage inverting example has 100 mA output max current but I need 200 mA. Can I get more current by putting a larger inductor? What is the limiting component?Cheers!

author: fourtytwo42
author_rank: Super Contributor
timestamp: September 30, 2021, 09:04:35 am
content: A decent data sheet helps like the original Motorola one herehttps://www.onsemi.com/pdf/datasheet/mc34063a-d.pdf

author: iMo
author_rank: Super Contributor
timestamp: September 30, 2021, 09:07:56 am
content: Go..gle for "online MC34063A calculator"
#344 midget flange bulb source in UK/Europe? - Page 1
Forum section: electronics / projects

author: MrSlack
author_rank: Frequent Contributor
timestamp: May 13, 2016, 09:37:17 pm
content: I've got a panel meter in a custom built guitar amp I'm tidying up for a friend. It has a #344 midget flange bulb in it that has gone pop. I can't find one of these anywhere in the UK. I've googled around and can only find it being a 10v 14mA part but there is nothing even remotely close available. There are 28v bulbs in the same package available but nothing lower. #344 Looks like a US part numberAny ideas or pointers appreciated!

author: dacman
author_rank: Frequent Contributor
timestamp: May 13, 2016, 10:09:34 pm
content: http://www.mouser.co.uk/ProductDetail/JKL-Components/344/?qs=sGAEpiMZZMvbyeSUH4qH%2fO9J1K6%2f1ePwhttp://www.digikey.co.uk/product-detail/en/jkl-components-corp/344/289-1260-ND/1553054

author: MrSlack
author_rank: Frequent Contributor
timestamp: May 13, 2016, 10:13:59 pm
content: Thanks for this. You know I actually looked on digikey and mouser and didn't see them.I'll go and sit in the corner and put my dunce hat onEdit: actually < £1 for the bulb and £12 for delivery. Nope.Think I might just convert this to LED.
34401A fft software? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: February 24, 2021, 07:43:43 am
content: Has anyone written a software package to let the 34401A act as a computer display oscilloscope or possibly FFT (dsa)?I know you can, I did it in excel before I think (may have been with a keithley GPIB, 7 years ago), but did anyone ever make like a real app for it?, not interested in 'use labview lol'.It should be able to do at most 100Hz or on higher settings a few Hz.
37+ Sensor Documentation Project - Page 1
Forum section: electronics / projects

author: 37Sensors
author_rank: Newbie
timestamp: August 09, 2018, 12:57:41 am
content: This is my project.http://37sensors.comIt is a website where I document the information that I have gathered on the "37 sensors" modules that I have purchased.Ever buy one of those 37 sensor kits? I've bought a few. And I've then discovered that the documentation on the modules that you get with a kit is a bit thin. I've documented what I have discovered about the modules on 37 sensors.com. I've also started making samples of how to code a microcontroller to use the modules. Little applications.I'd love to hear from anyone that has also used these modules from the various 37 sensors kits (and 20 sensors, 45 sensors kits) and has discovered any more information about the modules. Just leave comments on the modules page.I am also gathering my notes for the other little electronic modules that I've used like EEPROM, RTC, motor driver, LCD, radio modules, and others. I'll be documenting these as I dig up notes.CircuitGizmos (http://circuitgizmos.com) had been kind enough to supply me with the CGMICROKIT that is a 32bit processor board (in Arduino format) that I use for making code examples. They are also making a board specifically for the 37 sensors kit. CircuitGizmos also agreed to sell the sensors.http://circuitgizmos.com/37-Sensors-p109915115Here is a list of the modules that I have gathered documentation for:Analog Hall-effectAnalog JoystickAnalog TemperatureBall SwitchBi-color LEDButtonCharacter LCDFlameHall-effect SwitchHumidity and TemperatureIR ReceiverIR TransmitterKeypadLASERLight CupLiquidMercury SwitchMicrophoneMulticolor Flashing LEDObstacle AvoidancePhoto InterrupterPhotoresistorPiezo Driver or AnnunciatorPulseReed SwitchRGB LEDRotary EncoderServoShock and ImpulseSingle RelaySpeakerTemperature 18B20Temperature ThresholdTouch SensorTrackingUltrasonic DistanceIf you have used any of these and wish to add information to my project, I would certainly appreciate it. Also if you have any other modules that you need info on, please let me know - I probably have one in my collection.Thanks, David

author: 37Sensors
author_rank: Newbie
timestamp: August 10, 2018, 11:01:47 pm
content: Just added examples to the relay page:http://www.37sensors.com/relay/Every time I thought I was done, I found another type of relay to show.There are a lot more commonly available relays, but I think that this covers the spectrum of hobbyist modules reasonably well.

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2018, 06:18:09 am
content: Keeping up with China's production will likely be an endless job, at least until they become too expensive and everything shifts to some other country.There are also a bunch of relay boards with various ESP8266 and ESP32 modules onboard. The one I got isn't laid out well as it doesn't allow the ESP8266 to enter sleep modes. Maybe the next generation of it will fix that. Just wait and things change.
3843 SMPS question - Page 1
Forum section: electronics / projects

author: bogdan2014
author_rank: Regular Contributor
timestamp: September 17, 2020, 07:30:22 pm
content: I built this UC3843 based flyback SMPS and due to the voltabe feedback not functioning properly, the duty cycle would always be at maximum, so the current in the primary would rise and overcurrent protection would kick in. I tested the voltage feedback feature of the chip separately and it seems that the chip usually stays at max duty cycle with no FB voltage, but when the FB threshold is reached, the waveform goes directly to minimum duty cycle or shuts off. The balance is really fine, there's no in-between. Is that how it should function, or am I doing something wrong? Other chips, like the TL494 seem to have a finer balance. Or maybe the compensation is too weak?That also got me thinking that in normal conditions, the voltage feedback loop will also oscillate at its own frequency, and if it breaks, the above happens.

author: PKTKS
author_rank: Super Contributor
timestamp: September 17, 2020, 08:10:44 pm
content: No sure if that will help you but to put some things in clearyou should note that:- while UC38xx is mostly designed to operate in current modethus requiring a transconductance error amp... where almost100% of the amps are TL431 based..- TL494 is mostly designed to operate in voltage mode thusrequiring a more simple error amp where compensation isless critical than current mode and simpler, cheaperserror amps can be used.But TL494 also operates in several other schemaseven bucks or boost...UC38xx is a class of it is own hard to compare aupair w/TL494Paul
396 pin BGA , question regarding yield due to differences in line width - Page 1
Forum section: electronics / projects

author: Spikee
author_rank: Frequent Contributor
timestamp: October 13, 2016, 11:32:37 am
content: Hi all,I have a question regarding production yield / defects due to differences in line width in 300+ pin BGA devices.I got the design guide from this (Chinese) manufacturer but it has some things in it that make me doubtthat they are correct design practices.Around 50 pins of this chip are for different power pins and gnd pins. Most of these are concentrated in the middle.The design guide states that the line width for these should be >= 10 mil.All other signals are 4 mil (or 3.8 mil for usb ...).Would this difference in line width cause higher rates of fault during production ? (this is 1-10K production)Practice according to design guide:My thinking:The trace length is:16.69 mil (0.424mm).4mil trace resistance: 1.75m ohm10mil trace resistance 0.7m ohmThere is a full GND plane on L2.So there is actual (measurable) difference there. But how much resistance would a via add ?Since than It can be seen if this is a significant part or not.I don't know what a normal plating thickness is. Any Ideas?http://circuitcalculator.com/wordpress/2006/03/12/pcb-via-calculator/I'm just trying to figure out what the best design practice is.Thanks

author: DutchGert
author_rank: Frequent Contributor
timestamp: October 14, 2016, 04:31:16 pm
content: The first one for sure, you can even make the trace as wide as the BGA pad.What you want for power en gnd is low inductance.The difference in resistance between the two does not matter, the inductance does....As long as you have a good oven to reflow the BGA there should not be any problems. In theory a small trace acts as a thermal relieve but in a good over that preheats the board its no problem and you should go for good power integrityps. you are Dutch, draw and design in mm, not the mil/inch rubbish

author: DutchGert
author_rank: Frequent Contributor
timestamp: October 14, 2016, 04:38:46 pm
content: BTW, a TH via with a 0.2mm end size and a 0.4mm pad is not good design practice (and not IPC compliant). Make that via pad 0.6mm if you can or at least 0.45 or bigger.Read the design guidelines of the board manufacturer. Some examples:http://www.eurocircuits.com/PCB-design-guidelineshttp://www.we-online.com/web/en/index.php/show/media/04_leiterplatte/2011_2/relaunch/produkte_5/012012_Basic_Design_Guide.pdf
3D and Mobile Technology - Page 1
Forum section: electronics / projects

author: katedunl
author_rank: Newbie
timestamp: March 03, 2012, 12:47:17 am
content: We launched a 3D video called Bubble Mania on the Internet last year. It was designed to show off 3D on a smartphone that had 3D capabilities (HTC EVO 3D). I would love to hear feedback if you can watch it in 3D - you can also use 3D glasses.Please let me know what you think so we can incorporate into future videos. Thanks. k dHere it is:

author: Psi
author_rank: Super Contributor
timestamp: March 03, 2012, 01:42:54 am
content: don't need glasses to watch that, just go cross-eyed and overlap both images.

author: sydogg
author_rank: Newbie
timestamp: March 03, 2012, 09:58:03 pm
content: I dont understand! Who wants to view 3D on a phone? Besides that, can you tell us how you would create a 3D video that would be different for a mobile audience than a cinema audience. Wouldnt they be the same? I checked on YouTube, and you have a mobile version - what is the dif?

author: katedunl
author_rank: Newbie
timestamp: March 04, 2012, 06:47:13 am
content: As more people want to view videos on their mobile devices, more people will want the capability to view 3d as well. The mobile video of 3D Bubble Mania is enhanced for the mobile phone. Some of the 3d effects were altered to make them pop more on a handheld device. Did you notice any difference when you watched?
3D object tracking with digital magnetometers. (Personal project) - Page 1
Forum section: electronics / projects

author: PartialDischarge
author_rank: Super Contributor
timestamp: June 01, 2016, 09:10:53 pm
content: Wanted to share a project I did out of curiosity more than a year ago. Its a 3d tracker based on 3d magnetometers.It goes as follows, lets suppose you have a magnet in space and you want to know where it is. Four magnetometers are mounted at the corners of a square, each one providing a digital output of the vector field measured at that point. With those 4 3d vectors I ran an iterative algorithm, derived by myself, in a uP to come up with the distance from each magnetometer to the magnet.Here's a link to a video I just uploadedSome details follow:- The code is highly computationally intensive, with lots of trigonometrical functions, determinant and inverse matrixes. As I didn't want tochange the platform (Cypress Psoc5) I had to rewrite the code from C code with floating point numbers to fixed point operations (ever the trig functions) to make it faster. I also made the assumption that the magnet is always perpendicular to the plane, as it simplifies calculations. However the algorithm I came up and simulated in matlab is general- The magnitude of the vectors at each magnetometer is useless, ie the algorithm doesn't rely on the cuadratic or cubic decay of the field with distance. Only the angles (or the spherical coordinates) are useful here- The system lacks learning at this point, ie there's a mathematical model of the field a magnet generates, so any deviations between the magnet im holding atthat moment show up as error.- At power up, the magnetic field of the earth (a stationary unwanted field) is calculated and subtracted from all readings-Theres still the problem of nearby metals, that distort the received magnetic field and add up as errorcan't think of anything else right now. Cheers
pcbs - Page 1
Forum section: electronics / projects

author: luftek
author_rank: Newbie
timestamp: November 28, 2013, 10:09:51 am
content: _

author: MacAttak
author_rank: Unknown
timestamp: November 29, 2013, 11:33:09 pm
content: Too bad you didn't do this about one month earlier - I imagine most people who like to build kits would be interested in this just before xmas rather than getting it in January.

author: Stonent
author_rank: Super Contributor
timestamp: November 30, 2013, 06:54:52 am
content: I was thinking this was going to be about the Velleman kit.

author: calexanian
author_rank: Super Contributor
timestamp: November 30, 2013, 07:59:08 am
content: Yea!!!! Christmas spirit! Green solder mask and red led's. nothing says ho ho ho like that!

author: Stonent
author_rank: Super Contributor
timestamp: November 30, 2013, 08:26:00 am
content: Love the stolen Alibaba pictures.
3D pov display Full Design - Page 1
Forum section: electronics / projects

author: Quwat
author_rank: Newbie
timestamp: June 14, 2013, 07:29:48 am
content: Hello everybodyI feel my design is ready for the insanity check, so could you please read over it and point out anything I may have missed?Here is the document explaining my design.Thanks, this will help my school project a lot.

author: kizzap
author_rank: Unknown
timestamp: June 14, 2013, 09:27:32 am
content: Well I've gone and added a whole lot of comments, which I know you have seen.Things that I would look at, is the PCB trace width, and definitely loose those right angle connections on the top layer. This will aid in manufacturing.Can you also add images as to what you plan the visual output would look like?-kizzap

author: Quwat
author_rank: Newbie
timestamp: June 14, 2013, 12:29:42 pm
content: Oh yes the crime of 90deg traces, I ensured to avoid that when I was drawing the larger base of the traces. But when I used auto rought to get the top layers started, I forgot to change the settings and never got around to fixing it.Thanks for actually commenting what you were thinking, you have been the only one so far. Its surprising because there has be a large amount of people viewing it.I didn't expect so many people to be interested, I'm just a beginner. It was only about a year ago I was asking what a transistor is.I madestart of the year ( first processing program go easy), in some parts it shows a set-up similar to what I will have.

author: Christe4nM
author_rank: Unknown
timestamp: June 14, 2013, 01:15:29 pm
content: I've added quite bit of comments purely aimed at how document structure, lay-out etc. Lately I've been drilled how to write good reports, since we engineers somehow lack the skill, or better the will to do so. An example is to number every figure and give it a meaningful name. This prevents you as writer to just place a picture without reason to do so. Hopefully I won't come across as critical, and it'll benefit in the end.Good luck!
3d printed Case for a GPS GTPA010 Breakout  - Page 1
Forum section: electronics / projects

author: Erwin Ried
author_rank: Regular Contributor
timestamp: July 16, 2012, 05:02:14 am
content: This is a printed case with 2 parts:http://www.thingiverse.com/thing:26887Inside there is a cheap GPS module from ebay, GTPA010, an additionally my pcb includes 2 pins for enable the battery in the vbackup pin of the module and one for the "enable" because I want to keep the module full capacity to use via rx tx with microcontrollers. The datasheet describes 2 interfaceshttp://screencast.com/t/teY5OC5N9ry,I bundled both.And here is a video of the process of making the case:I found making a simple version of your internals with cuboids allows you to make a nice case very quick! Otherwise is nearly impossible at least with simple tools like Google Sketchup.

author: george graves
author_rank: Super Contributor
timestamp: December 07, 2012, 09:56:54 am
content: Impressive work!

author: robrenz
author_rank: Super Contributor
timestamp: December 07, 2012, 12:21:35 pm
content: Great job!
3D printed guitar with an STM32 micro, some LED's and a little FFT magic - Page 1
Forum section: electronics / projects

author: joshendy
author_rank: Newbie
timestamp: December 17, 2020, 09:46:18 pm
content: I thought some here might be interested in seeing my project that I recently finished. I 3D printed a guitar and put together a relatively basic PCB that amplifies the guitars output and pops it into an ADC where I use an FFT algorithm to convert it into frequency components that dictate how it drives 50 APA102 LED's that are mounted in the guitar. In short; it lights up when you play it.The micro is an STM32L431. Powering the micro is the LTC3240 3V3 regulator. For the LEDs and opamp bias is the TPS61022 5V regulator. Analog side of things: precision reference IC is TLE2426CLP, opamp is TLV3542, ADC is ADS8319.Here's a video of it in action and also details on how I designed and built it:https://youtu.be/u3JaJUOe9As

author: Mr.B
author_rank: Unknown
timestamp: December 17, 2020, 10:06:48 pm
content: Colour me impressed.Well done.

author: graybeard
author_rank: Frequent Contributor
timestamp: December 17, 2020, 10:46:46 pm
content: Nice!!
3D Printed Multimeter Probe - Page 1
Forum section: electronics / projects

author: Ferroto
author_rank: Frequent Contributor
timestamp: December 01, 2019, 04:00:00 pm
content: I have always been disappointed with the performance of my multimeter leads and have always wondered why most are as sharp as a blunt pencil. after being inspired bygiufini's PCB Workstationon Thingiverse I decided to make a set of fine point multimeter leads out of a sewing needle and a 3d printed body.https://imgur.com/a/3QKselIThe only issue I had was designing the hole for the needle. The needle is 0.035" (0.889mm) (sorry for the odd metric number I only have an imperial micrometer) in diameter however the plastic would shrink as the part printed I found after some experimentation that a needle bore of 1.3mm would result in a snug press fit for a 0.889mm sewing needle. Also my first print had clearance issues for the 20 Gauge ferrule not sure if it was the same contraction issues as with the needle bore or if my micrometer was compressing the plastic sleeve. After some experimentation I was able to resolve the clearance issues with the ferrule as well.This probe is good for fine pitch components however I'm going to experiment with acupuncture needles. My theory is that they are sharp enough to probe through the solder mask but I won't know until they arrive.

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 03, 2019, 06:32:55 pm
content: Did you post your design on thingiverse? This inspired me to order some accupuncture needles but it will be some time before they arrive from china...lol
3D Printed PLA Plastic Electrostatic Motor - Page 1
Forum section: electronics / projects

author: imk
author_rank: Regular Contributor
timestamp: June 29, 2021, 10:34:20 pm
content: Hello thought you guys might like to see this.It was made a few years ago to see if an electrostatic charge could be focused.So i arranged the stator blades at an angle pointing across the face of the rotor faces.As can be seen the motor tries to start but gets stuck due to the shaft having bit of bend it it.However the motor will only run one way, even if you spin it in reverse it always stalls and tries to spin anticlockwise.Some months after building in the conductive paint started to fall of the PLA parts so the motor has not run for two or three years.So electronic eng. friend wants to see it running so i stripped it down, sanded the parts.Coated the rotor faces and stator vanes with Gorilla Glue and just before it went hard I applied the conductive paint again.https://youtu.be/OHMpbJIXWtEoriginal video pre new axilIt runs again, so today I ordered some carbon fiber tubes to replace the bend axil, I hope this fixes the start stall :-)imk
3D printed project case? - Page 1
Forum section: electronics / projects

author: matthewell
author_rank: Newbie
timestamp: August 15, 2011, 11:01:23 pm
content: hey i was wondering if there would be any interest in custom 3d printed project cases (or pretty much anything elce that can be 3d printed)I'm yet to decide on a exact price point but my aim is to keep everything cheap so <£50 and that will include the design work.so if anyone is interested or has any feedback feel free to contact me.matt
3D Printed Smart Watch Bluetooth/UART Feedback and Guidance - Page 1
Forum section: electronics / projects

author: willz1200
author_rank: Contributor
timestamp: September 02, 2014, 08:40:33 pm
content: Hey EEVBlog ForumOver the past month or so I have been designing an Atmel/Arduino powered smart watch, the reason I am posting here is to request feedback and guidance on its programming interface and the watch in general, the watch will be Bluetooth enabled, have an oled screen and a five way joystick. My concern is whether I should allow it to be programmed over Bluetooth or have an FTDI or other USB to UART chip on board (the watch will have Bluetooth regardless). I have achieved arudino programming over bluetooth in other projects, it just requires Bluetooth to virtual com port drivers and a small reset circuit. So basically all I ask is your opinion on whether I should make the watch programmable over Bluetooth or using the UART, as I am having trouble deciding.A few solutions I thought of:- Bluetooth and reset circuit only- Pads available on the circuit board for the user to add reset components if they want to program it over Bluetooth- adding a USB to UART chip for wired programming- using an AVR with two serial lines so both can be used without the need of a header to switch modesHere is a YouTube video I made with lots more detail if your interested in the watch, check the description for an overview and specs:Thank You,Will
3D printed TO-92 Adapter for easy heatsink mounting - Page 1
Forum section: electronics / projects

author: Shay
author_rank: Regular Contributor
timestamp: July 05, 2024, 10:41:56 pm
content: This is the result of an issue I encountered, as I wanted to sense the temp of some heatsink for a project using the good old LM35 temp sensor, since its common and just about everywhere, very cheap and easy to use. NTC are harder to mount on heatsink as you need the ones that are epoxied to the ring, which are more expensive overall.Additionally, while LM35 are available in TO-220 package, they are often twice as costly and less readily available unless purchased from major distributors.So I quickly designed some kind of an TO-220 with a small TO-92 shaped slot in the middle:After printing it came out like this:It attaches the TO-92 firmly to the heatsink, the use of thermal paste is recommended.Might be useful for some of you

author: sourcecharge
author_rank: Regular Contributor
timestamp: July 05, 2024, 11:20:39 pm
content: Nice idea.I'll keep it in mind
3d Printer ATX power distribution and control board. - Page 1
Forum section: electronics / projects

author: TbirdMan
author_rank: Newbie
timestamp: April 16, 2016, 05:10:53 am
content: Hello there. I am an Engineering Physics grad student in the USA. I have decided to take on a fairly simple project for my first PCB design. The design is intended to allow the adaptation of a standard ATX PSU to supply a 3D printer. the ATX plug is broken out to a header for the PS_ON and PWR_GOOD pins. there is a USB pass through that has a select-able (via jumper) +5v source between 5v standby, the main 5v from the PSU, or the USB input 5V bus. this will allow the electronics package to be powered independently of the ATX power supply so the controller can turn the ATX supply off when not needed. I also decided to breakout some 5v and 3v3 general purpose pins (they're there so why not?). the main rails are powered by two 6 pin PCIe power plugs and are intended to provide up to 15A each with a fuse in line.what I am hoping for help with is the main rail design. I think the GND should be ok for 30A, but the 12V lines are what concerns me. I have left the mask off the traces to allow for adding solder to beef up the capacity, but I would prefer not to have to do that. the width at the narrowest is 4mm but the traces are doubled up top an bottom so it is more like 8mm but I understand that top and bottom is not exactly the same as doubling the capacity. I am including images of the top and bottom for reference, let me know if you need anything else.

author: prasimix
author_rank: Unknown
timestamp: April 16, 2016, 09:20:13 am
content: Quote from: TbirdMan on April 16, 2016, 05:10:53 amWhy is that? I know that internal and external layers is not the same when we talk about temperature rising for the same current but top and bottom external layers should be the same. 8 mm can deliver almost 11 A with 10oC increase on 36 um cooper (KiCad calculator, see picture in attachment).

author: TbirdMan
author_rank: Newbie
timestamp: April 16, 2016, 03:07:37 pm
content: You may be right, again I am new to this, but approaching this from a physics standpoint, one path for the trace to dissipate heat (into the PCB) is shared by the top and bottom. I would assume this would result in less efficient dissipation by the PCB since you are putting twice the heat into the same effective sinking area. I think I am gonna make the board a bit wider and add a couple mm to each trace. that should allow the traces to carry the current without the need of extra solder. when I get the boards made I will run some static load tests at 15A to see what kind of heat rise I get. Again, this is new to me, so any input is welcome.
3D printer electronics - Page 1
Forum section: electronics / projects

author: philn
author_rank: Newbie
timestamp: April 18, 2014, 01:02:09 pm
content: Hey @all,I (electrical engineering student) am currently working on a mainboard design for a 3D printer that im planning to build with a friend of mine (he's a mechanical engineering student). My goal is at the moment to finalize the schematic of the main board. It includes drivers for the heaters, stepper motors and fans and has inputs for thermistors and end stops. It's pretty similar to theRUMBAexcept that I'm planning to use a XMEGA micro und some other mods (and that I design it myself, of course :-) )I just published it on Github:https://github.com/mbb01x/SallySprinter(Schematic PDF) and I'd appreciate any hints or improvements from you guys.I'm also going to post the board layout as soon as I got sth to show.Thanks,Phil
3D step file for cable clamp (type used for 1110 Utility box) - Page 1
Forum section: electronics / projects

author: Jester
author_rank: Frequent Contributor
timestamp: March 03, 2023, 12:15:03 am
content: I'm looking for a step file for this type of connector or something very similar, they refer to these as a 1/2" cable clamp, even though the actual knockout holes in the 1110 Utility boxes are actually 7/8"[attachimg=1

author: thm_w
author_rank: Super Contributor
timestamp: March 03, 2023, 12:27:10 am
content: Is this for 3D printing or for modeling?mcmaster has some but not really that style:https://www.mcmaster.com/armored-cable-connectors/https://www.3dfindit.com/en/cad-bim-library/manufacturer/abb-installation-products/conduit-and-cable-fittings/rigid-and-intermediate-metal-conduit-fittings?path=thomas_betts%2Ffittings%2Frigid_fittingsI would just sketch an approximate if not.

author: Jester
author_rank: Frequent Contributor
timestamp: March 03, 2023, 01:35:07 pm
content: For modeling and that is close enough for this model.Much appreciated, I was unaware that McMaster had step files, one more source.

author: AndyC_772
author_rank: Super Contributor
timestamp: March 03, 2023, 02:21:29 pm
content: Might be worth a look onhttps://www.3dcontentcentral.com/
3D Time of flight cameras - Page 1
Forum section: electronics / projects

author: sagnikbasu
author_rank: Contributor
timestamp: February 02, 2017, 07:26:21 pm
content: Can there be any innovative use of Time of flight camera systems other than depth measurement?

author: PointyOintment
author_rank: Frequent Contributor
timestamp: February 03, 2017, 12:42:28 am
content: Yes.

author: Brumby
author_rank: Unknown
timestamp: February 03, 2017, 02:07:20 am
content: * riveting thread *

author: stevelup
author_rank: Regular Contributor
timestamp: February 03, 2017, 11:24:56 am
content: They're used for gesture control in the latest generation of BMW cars.Have a look at the PDF.First post here by the way. Hello everyone

author: Brumby
author_rank: Unknown
timestamp: February 03, 2017, 12:20:16 pm
content: Quote from: stevelup on February 03, 2017, 11:24:56 amG'day ... and Welcome.

author: stevelup
author_rank: Regular Contributor
timestamp: February 03, 2017, 03:44:08 pm
content: Cheers!

author: mark03
author_rank: Frequent Contributor
timestamp: February 03, 2017, 08:31:17 pm
content: No.But there are some innovative applications of depth measurement that I'd like to see. E.g., depth-enabled security cameras should make reliable motion detection a snap.

author: ebastler
author_rank: Super Contributor
timestamp: February 05, 2017, 03:35:41 pm
content: Quote from: sagnikbasu on February 02, 2017, 07:26:21 pmHow about fluorescene lifetime imaging?(Measure the lifetime of the excited state of a fluorescent dye. Changes in the lifetime can be used to sense the biochemical environment of the dye, or to detect its colocalization with another dye, causing resonant energy transfer that shortens the fluorescent lifetime.)http://www.mit.edu/~ayush/FLIToF/FAQ.html

author: mmagin
author_rank: Frequent Contributor
timestamp: February 06, 2017, 08:25:50 pm
content: So, these devices don't necessarily run at a high frame rate, but they have a very repeatable and uniform temporal response across the entire pixel array with respect to some synchronization pulse?
3PDT Pushbutton switch part find - Page 1
Forum section: electronics / projects

author: belzrebuth
author_rank: Frequent Contributor
timestamp: December 06, 2018, 07:39:12 pm
content: Hi all,I'm searching for a 3PDT pushbutton for a balanced audio passive mute switch.The diagram of the mute switch is this :https://www.gearslutz.com/board/attachments/geekslutz-forum/331457d1361367895-how-wire-external-xlr-off-switch-pedal-balanced-mute-switches.jpgI've already implemented it using a standard toggle 3PDT switch but I'd like to find a latching pushbutton instead.I can only find the typical stompbox-type foot switches which are hard to press by hand.Has anyone have any idea of a pushbutton switch that could work?I was thinking something like thishttps://ae01.alicdn.com/kf/HTB1i5fbKVXXXXceXpXXq6xXFXXXU/Factory-Supplied-3-Pcs-2P-SPST-Spring-Loaded-Locking-Push-Button-Switch-5A-40A-250V-AC.jpg_640x640.jpgbut ideally I'd want something like a stompbox switch with far lighter toggle force.

author: Gyro
author_rank: Super Contributor
timestamp: December 06, 2018, 07:52:38 pm
content: Silly question, but have you tried looking for 4PDT? - 3 is a bit of an odd number.E.g.https://cpc.farnell.com/search?st=4pdt

author: belzrebuth
author_rank: Frequent Contributor
timestamp: December 06, 2018, 08:25:43 pm
content: Haven't looked for more than 3 poles because that's also kind of overkill for my application (one set of leads is NC) and my aluminum enclosure is tight enough for a 3PDT to fit in so...EDIT:a DPDT switch could also work; I just happened to have a 3PDT when I was making this so I just used that..There is no need for a 3PDT necessarily