hybridfree/eevblog-posts huggingface dataset:
gate driver boost converter IC for IGBTs - Page 1
Forum section: electronics / beginners

author: LaserTazerPhaser
author_rank: Regular Contributor
timestamp: June 10, 2019, 10:02:17 pm
content: Whats a decent boost IC for supplying maximum Vge voltage to gate drivers charging IGBT gates only high side within 120nc-290nC?These aren't IGBT modules only TO247 parts going to =<20Khz likely ceramic caps would be required for boost filtering.

author: Giaime
author_rank: Regular Contributor
timestamp: June 11, 2019, 06:55:40 am
content: I like the SN650x from TI, you get a nice isolated supply this way, and there are off-the-shelf transformers ready made (e.g. from Wuerth Elektronics).
Gate driver module for mosfet/IGBT - Page 1
Forum section: electronics / beginners

author: Mm
author_rank: Contributor
timestamp: November 30, 2023, 06:43:59 pm
content: Hello,Im looking for gate driver module to switch n-mosfet/IGBT.It should have capability to adjust duty cycle and frequency.Frequency should go higher than what ne555 can do, minimum 1MHz. Signal should be square wave.This seems decent:https://a.aliexpress.com/_mNIFvWMWhat kinda options you guys know? I would rather buy ready module rather that try to build one.

author: Jwillis
author_rank: Super Contributor
timestamp: November 30, 2023, 11:24:40 pm
content: I suppose you would be alright with than module.I'm a little leery of the 6A current capability. Suspicion is based on other products making unrealistic claims.Switching speeds of IGBts are quite a bit slower than MOSFETs . Typical IGBTs range from 20Khz to 80Khz. Where as MOSFETs will range much higherThe 555 timers can very. The TLC555 has a maximum frequency of around 2Mhz and the XTR655-D goes as high as 4Mhz. Aside from maximum supply voltages they are both drop in replacements for the NE555
gate driver transformer 1:1:1 - Page 1
Forum section: electronics / beginners

author: croyleje
author_rank: Regular Contributor
timestamp: October 29, 2012, 07:37:25 pm
content: hello everyone i have been doing a little research on LLC resonant half-H converters and came across something i don't understand. below is a simple diagram of a 1:1:1 gate driver transformer and i understand the controller sends a signal in the primary one side or the other [pos or neg] depending on which gate you want to open, but in all the schematics i found the MOSFETs are all N-Channel so why don't both turn on? maybe i am just being an idiot but i would think both would come on. if anyone knows a simple explanation would be nice thanks for the help.jason

author: Rerouter
author_rank: Super Contributor
timestamp: October 29, 2012, 07:44:02 pm
content: one of those gate coils should be the other way around, the normal usage is while one of them is slammed positive and fully conducting, the other is slammed negative and in full cutoff,

author: croyleje
author_rank: Regular Contributor
timestamp: October 29, 2012, 08:26:23 pm
content: so the secondary coil orientation is what makes that coil positive or negative thank you

author: Zero999
author_rank: Super Contributor
timestamp: October 30, 2012, 10:00:35 am
content: There should be dots on the coils to denote the phase.
Gate resistor value - Page 1
Forum section: electronics / beginners

author: sureshot
author_rank: Regular Contributor
timestamp: June 06, 2018, 09:57:07 am
content: So i want to put a crowbar circuit together, i had a schematic but the SCR thyrister is obsolete. I can source similar SCR thyristors but the gate trigger current is lower, but gate voltage is about the same. I'm looking to calculate the residence value for another SCR with a 0.020 mA trigger gate current instead of 0.040 mA of the obsolete device. My zener diode is 16 Volts 5 watts. My question is do i calculate the gate trigger resistor as follows 16 Volts - 1.5 V / 0.020 mA. Can anyone advise if that's how to calculate it. I'm not sure as the zener reverese voltage won't kick in until its above 16 Volts.Thanks for reading, any help appreciated.

author: Zero999
author_rank: Super Contributor
timestamp: June 06, 2018, 11:22:20 am
content: Just use the same value resistor. The SCR trigger current is a minimum value. Exceeding it will not do any harm. In this case, even if it does exceed the maximum rating, once the crowbar has kicked in, it will drop to a safe level, very quickly.You might get more help, if you post the schematic and part numbers.

author: sureshot
author_rank: Regular Contributor
timestamp: June 06, 2018, 12:10:37 pm
content: Thank you for your help. The obsolete SCR had a gate current of 40mA and the one I'm thinking of using has gate current of 15mA . The voltage for the gate is 1.5 Volts for both dvices. In the circuit diagram the gate current limiting resistor is 470 ohms. Will it not make a difference as the gate current is 25mA less than the obsolete device. Thanks again.
GBU406 suited for Mazzilli ZVS driver? - Page 1
Forum section: electronics / beginners

author: Molenaar
author_rank: Regular Contributor
timestamp: June 18, 2016, 10:37:48 am
content: Usually diodes like the UF4006 or MUR460 are recommended, but I don't have them at the moment, so I thought about some GBU406's I salvaged from an ATX PSU.I assume diode recovery time is mainly governed by capacitance and internal resistance, effectively forming an RC filter (correct me if I'm wrong). Recovery times are not mentioned in the datasheet, but the capacitance is double to tripple that of an UF4006, but lower than the MUR460.Would this mean the GBU406 would be usable, albeit maybe not optimal?

author: alsetalokin4017
author_rank: Super Contributor
timestamp: June 18, 2016, 02:24:03 pm
content: That's a full-wave bridge, isn't it?Could you post the circuit diagram you plan to use for your Mazilli driver using a FWB instead of discrete diodes?

author: Molenaar
author_rank: Regular Contributor
timestamp: June 20, 2016, 08:57:45 pm
content: I was just thinking about using one diode from the bridge, nothing special.
gear 0.3 - Page 1
Forum section: electronics / beginners

author: uc
author_rank: Contributor
timestamp: June 02, 2018, 05:02:51 pm
content: Gear 0.3I need understand soldering equipment and consumables for SOIC pins and smaller format?Please propose magnifying glass and tools enable the work.Maybe to much input for easy answer, but please try?//uc

author: larsdenmark
author_rank: Regular Contributor
timestamp: June 02, 2018, 06:20:31 pm
content: Unless you want to spend weeks learning this stuff and perhaps months to be good at it I would say that it is not worth it.For ICs that are only available as SOIC or other surface mount sizes you can often get breakout boards where the components are presoldered and the connection are available in sizes that work on breadboards and can soldered without the use of microscopes. E.g. see onwww.sparkfun.comI would just reorder the ICs you need as DIP if at all possible.If you really must learn about soldering these small components then this video is a good place to start:Note that Louis Rossmann has thousands of videos many of which are more than an hour long so starting to watch his channel is quite time consuming :-)

author: rstofer
author_rank: Super Contributor
timestamp: June 02, 2018, 10:39:12 pm
content: I just use my Hako 936 soldering station with a 1/8" tip. I use ordinary solder (0.024" diameter) with a lot of paste flux. Flux is the key to getting the solder to flow between the pins and pads. It is critical for SMD devices.If the project has a lot of 0805 packages, I will use solder paste on the pads, set the parts and then do a reflow solder in my converted toaster oven. If the board is small enough, a hot plate works just as well.I put the vast majority of the parts on the top of the board, especially if I'm going to reflow. Then if I have to add some decoupling caps, I put them on the back side and solder them by hand.This just isn't something to get all wrapped up in.I have a hot air tool and I never use it. I'm not trying to remove/replace BGAs, just simple chips with pins.The best way to remove chips is to cut the pins and then remove them one-by-one. It puts a lot less stress on the board and there is less chance of pads lifting. Perhaps a hot air tool would work better but I have never needed it.
Geberit Sigma80 touch free flushing (toilet) - 2 wire servo control  - Page 1
Forum section: electronics / beginners

author: Thorsten42
author_rank: Newbie
timestamp: January 02, 2024, 07:53:23 am
content: I'm having trouble with my Sigma80 touch free flushing plate from Geberit.https://www.geberitnorthamerica.com/products/actuator-plates-and-flush-controls/sigma-series-flush-plates/sigma80/The LEDs on the plate are showing a flush request has been identified and the subsequent flush has been executed but the servo lever is not moving.The puzzling part is that the servo used by Geberit looks like a regular RC Servo with three connections (+V, GND, PWM_Signal) but when I open the plate I see that it only uses two connections to control the servo.Unfortunately the servo is potted so I don't know which connection is which to check the servo by itself, when I measure the resistance on the three pins coming from the servo it shows more or less reasonable values which confirms my assumption that it is indeed a regular RC servo.Since it is not moving as expected I don't know at the moment if the servo or the plate unit is kaputt.When I measure the output of the plate connecting to the servo (as mentioned just two pins/wires) I get 2V (or -2V as I don't know the polarity) when idle and a -5V (or 5V) PWM signal when flush is activated, I "think" I can also spot the difference between flush for "number One" or "number Two" based on the length of the PWM signal.How can a regular RC servo just be controlled over two signals and which one would that be, I've spare servos at home but would need to know which signals I should connect them to check which part is faulty.At the plate side one of the two servo connectors is directly connected via a couple of resistors to an output pin of the TI MSP430F532 and the second one I still need to figure out.Any help is highly appreciated 😊

author: liaifat85
author_rank: Regular Contributor
timestamp: January 03, 2024, 03:49:08 pm
content: Carefully examine the circuit on the Geberit Sigma80 plate. Identify the components connected to the servo wires.
General advice on scale project - Page 1
Forum section: electronics / beginners

author: swollavg
author_rank: Newbie
timestamp: January 09, 2015, 03:43:39 am
content: Greetings!I'm an electronics beginner and am looking for some general advice on how to go about a project.I am looking to hack a digital food scale. I want the scale to take a measurement every hour and to send this data to a user's profile on a web application.I do some web development and can build the web applications with Rails. I am not sure how to construct the digital scale hack and have it send the data over WiFi.Here are 2 articles that I found which would be very similar. They use a body weight scale and send the data to a Google document. This seems very similar to what I am trying to accomplish.http://www.open-electronics.org/wi-fi-body-scale-with-arduino/http://gadgetmakersblog.com/hacking-kitchen-scale/I am wondering if this would be feasible given my skill level? Is what I am trying to build too complicated for a beginner, even with these step by step tutorials and guidance from forums etc?In general how difficult would this project be for someone with the experience?Just a note, I have a lot of time to spend on this.Thanks!

author: edavid
author_rank: Super Contributor
timestamp: January 09, 2015, 03:53:54 am
content: Perhaps you could get a USB postal scale and connect it to a laptop. You would have to find one that doesn't need to be turned on manually.

author: swollavg
author_rank: Newbie
timestamp: January 10, 2015, 03:10:10 am
content: Hey there. I would need it to be wireless. Do you think it's possible to hack a common digital food scale?I found a few more articles that are similar to what I am trying to do.http://jdesbonnet.blogspot.com/2010/10/computer-interface-to-low-cost.htmlhttp://electronics.stackexchange.com/questions/18266/hardware-required-for-measuring-small-weight-changes

author: edavid
author_rank: Super Contributor
timestamp: January 10, 2015, 04:03:28 am
content: Isn't a laptop wireless?

author: sleemanj
author_rank: Super Contributor
timestamp: January 10, 2015, 04:06:59 am
content: Quote from: swollavg on January 10, 2015, 03:10:10 am
Delete Delete Delete - Page 1
Forum section: electronics / beginners

author: The_Almighty_Bacon_Lord
author_rank: Contributor
timestamp: February 11, 2017, 11:10:20 pm
content: Delete Delete Delete

author: helius
author_rank: Super Contributor
timestamp: February 11, 2017, 11:43:59 pm
content: Of all those components, the tubes are the most obviously life-limited (was the display already used for several years?) Over time the cathodes emission degrades. Since there is no heater, they then have difficulty lighting when cold, leading to flicker but not much light.The inverter has switching transistors that could fail short; I don't know if the transformer often fails.

author: Monkeh
author_rank: Super Contributor
timestamp: February 12, 2017, 12:16:56 am
content: Have a listen and a feel around the ends of the tubes. Sometimes the leads come off.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 12, 2017, 12:34:39 am
content: Could also be HV breakdown starting to happen somewhere, but most likely aging tubes.

author: Cliff Matthews
author_rank: Unknown
timestamp: February 12, 2017, 01:22:09 am
content: If I recall ELO makes good touch screens. You could retrofit this to LED. Several hands-on examples exist on YTube:https://www.youtube.com/results?search_query=CCFL+Backlight+conversion+to+LED

author: helius
author_rank: Super Contributor
timestamp: February 12, 2017, 01:23:42 am
content: Quote from: The_Almighty_Bacon_Lord on February 12, 2017, 12:59:26 amPartly because there are no heaters to pre-warm the cathodes, starting a CCFL takes high voltages, up to 3kV. That can be enough to blow through the insulation between the transformer windings. Since you can't see through the transformer, it's hard to detect this. The result would be that the output voltage doesn't rise high enough to start the lamp.

author: helius
author_rank: Super Contributor
timestamp: February 12, 2017, 05:35:11 am
content: A CCFL isn't "filled" with mercury: the amount is a few milligrams, and you would have to physically bend it for it to break. Inverters with a different design will have transformers with different properties; if the circuit doesn't resonate it simply won't work.

author: soul40k
author_rank: Newbie
timestamp: February 13, 2017, 01:12:25 am
content: My best advice is to never trust capacitors. Even if they are not bulged, they could still be far too degraded to do their job properly.
General considerations about getting a New HH DMM  - Page 1
Forum section: electronics / beginners

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 18, 2011, 11:36:20 am
content: I had accidentally found this link ..http://www.freepatentsonline.com/article/EE-Evaluation-Engineering/175075101.htmlWell it is the most well written explanation of what you must have in mind ,when you think about getting a new DMM.The selection of a new DMM , its an very complex process, for beginners and professionals.I found lots of help by reading the above.That's why I am suggesting to read it too.Theoretically , some one should make a list of the " candidates " who offers the most needed functions to him.And them , he explores the others factors , like pricing & reviews.In all my life I was avoiding to become Brand loyal ,this helped me allot in time , and now I own few, but really worthy tools.Enjoy the link above. :-)
General Purpose P-Channel FET with reversed Source-Drain? - Page 1
Forum section: electronics / beginners

author: Arznei
author_rank: Contributor
timestamp: October 16, 2019, 04:50:41 pm
content: Hello everyone,I ordered a few PCBs and beeing the dumb me that I am, I got source and drain mixed up on one FET.So, I searched for a replacement, but I couldn't find _any_ P-Channel FET with the same package that had source and drain the other way around. For reference, I planned on using the SI2319DS-T1-E3 which comes in a SOT-23 package with G-S-D pinout. But to fix my PCB I would need a G-D-S pinout in a SOT-23 package.The parameters to this FET are not critical at all. It should be able to handle up to 150mA current with Vgs at -3.3V.So, does anyone know of a FET with that pinout and package? Do they even exist?Thank you for any help!

author: magic
author_rank: Super Contributor
timestamp: October 16, 2019, 05:24:44 pm
content: I have only ever seen SOT23 (and any other SMD) transistors in one pinout, but I haven't seen more than a few dozen different types to be honest.I'm afraid this pinout is kind of standard, after the mess that all the different TO92 pinouts were.If it's not for a commercial product which needs to look pretty, you could perhaps mount this one transistor upside down.
General purpose transformer? - Page 1
Forum section: electronics / beginners

author: scatterandfocus
author_rank: Regular Contributor
timestamp: September 20, 2019, 02:26:38 pm
content: I was going to add a 6.3V filament transformer to my components order list for use in an octopus component tester. But maybe I should consider something with higher voltage and current handling for more general purpose use, such as making a first-time linear power supply circuit, and more safely scoping mains. What other sorts of things could a general purpose transformer be useful for to a beginner? What voltages, current handling, and other aspects might be good in a general purpose transformer? Of course, a single transformer isn't going to be efficient for a range of uses, but it could be useful for exploring a range of beginner projects.

author: Stray Electron
author_rank: Super Contributor
timestamp: September 20, 2019, 04:14:35 pm
content: I would suggest looking for a variac so that you can set the voltage anywhere you want. OTOH for any use that the operator might be exposed to the output then you'd need to use it with an isolation transformer. BUT both devices are very useful on their own. Both would be expensive to buy new but it's not difficult to find used ones on a site like E-greed or in surplus industrial equipment.I have several variacs including one permanently mounted in a chassis along with a voltmeter and an ampmeter and wired to a standard AC outlet. I use it anytime that I fire up an old piece of electronics gear in an effort to reform the capacitors in it and also to watch for possible shorts before I apply enough power (voltage) for a short to cause significant harm.IMO there's not really such thing as a general purpose transformer. They're made for a WIDE range of output voltages and currents.

author: ledtester
author_rank: Super Contributor
timestamp: September 20, 2019, 05:23:24 pm
content: Transformers tend to be heavy, so I would try to find them locally. A good place in the US are "thrift" stores like Goodwill, Salvation Army, etc. Also check if there are any "surplus" stores in your area.An mains powered clock radio will contain a small low-voltage transformer like shown here:https://youtu.be/M_FlSzwDKC4?t=1m20sThere are a lot of other older consumer goods that were powered by transformer wallwarts. They'll say they are DC power supplies, but if they are heavy for their size and look more like a cube rather than being rectangular it means there is a transformer inside. For instance, in this wallwart:there is a transformer, rectifying diodes and capacitor.
General question about CAN controllers and the Tx ordering of messages - Page 1
Forum section: electronics / beginners

author: e100
author_rank: Frequent Contributor
timestamp: July 09, 2022, 03:20:40 pm
content: Whilst reading about the NMEA 2000 Fast Packet protocol I saw mention of problems with CAN controllers not sending messages in the order they are pushed onto the Tx queue. Is this a general behavior of all CAN controllers, or only some?I kind of assumed that they work on a strict FIFO principle, but is it more complicated that that. I know some can prioritize the Tx order based on the CAN id but I think this is a different issue.

author: Siwastaja
author_rank: Super Contributor
timestamp: July 09, 2022, 04:09:23 pm
content: Different CAN controllers offer different possibilities.Most offer some kind of FIFO in which order is preserved. Some additionally offer features like two FIFOs with different priorities, dedicated buffers from which messages can intervene between FIFO pulls, and so on. Always read the documentation of the controller you use.That being said, it is a poor design to rely on a certain packet order; that suggests it also can't fail gracefully with packet loss. If your messaging requires multiple packets, as is often the case with tiny 8-byte payload of CAN, you would like to have some kind of sequence numbering, in ID or data itself. If you have some complicated action sequences that need to be done in right order, sending acknowledge packet, and looking for that ack before going to the next state would be a great idea.I don't know if SAE J1939 has such inherent design flaw, but if it does, then indeed be careful with data ordering. Anyway, in robust CAN, you have to somehow deal with packet loss. Remember, packets are acknowledged by any active node, so CAN's acknowledgement is worthnothingin multi-node system. Very typical, robust and simple way to deal with this is just flood the interesting data often enough, and use some kind of timeout fault recovery / limp home procedure in case the important data has not been seen for a while.
General Questions about Switching regulator Designs - Page 1
Forum section: electronics / beginners

author: LoveLaika
author_rank: Frequent Contributor
timestamp: May 22, 2020, 11:02:00 pm
content: I'm working on a switch-mode power supply to provide a positive and negative voltage. I've posted my current working design on the other Design/Project forum for some general advice (as I'm new to working with buck regulators), and after some comments and feedback, I realized that I still need to tweak it. In that sense, and after viewing some posts here about some magic smoke, I wanted to ask some general questions regarding working with buck regulators.1. Is there a general rule of thumb of how much supply current is used for a buck regulator? I'm using a 15-volt source to generate a positive and negative voltage. The output loads aren't very much, just like 300 mA for testing in simulation, but my source is giving out 5 amps. Simulation is not always a good model for real world applications, so I wanted to ask here based on people's experiences.2. Is it a good idea to put two 'separate' buck converter circuits on the same PCB? I'm using the LM2673 for it's current adjustment pin. While each regulator generates its own voltage, they both draw from the same supply voltage. They would share the same ground plane, but would there be issues with interference from each other?3. What sort of protection should be considered when building a buck regulator circuit? TI's app-notes and datasheets provide a lot of help when designing the regulator, but once it's built, is it fine to just route the output voltages to a connector, or should there be some protection involved?4. Is a buck converter really the best idea? This may seem like a bad question since I'm already working with a design, but I'm always on the look for new ideas and inspiration. When I first started this project, I first thought of linear regulators like the LM317/LM337. Given that my output load would range from roughly 80 mA to 500 mA at most, I thought it would be a great idea. However, after some research, I found that linear regulators were inefficient and needed large heatsinks. That's when I looked at buck regulators. They seemed more complicated, but they also seemed like they would get the job done and then some without the necessity of a massive heatsink. Are there any advantages to using linear regulators instead of switching converters?
Generate Chirp Signal using Arduino & Si5351 - Page 1
Forum section: electronics / beginners

author: Guahluh
author_rank: Newbie
timestamp: November 07, 2021, 05:24:33 pm
content: Helo everyone,I allow myself to join you to know if it would be possible to have additional information concerning the Si5351 module.My need would be to use this module to emit a pseudo-periodic signal (aka chirp) looking like this:]-a chirp between 1 600 Hz and 300 Hz and with a sweep repetition rate of two to four times per second- ?I already have an Arduino Nano for driving as well as the Si5351 module, but I wanted to get your opinion on my project, because I have trouble finding information regarding the generation of this kind of signal ? Is this already achievable ?In advance, thank you for your answer.Edit.: I just realized my gross mistake concerning the choice of the module, which is clearly not designed to emit these frequencies.Would you have a better alternative ?

author: radiolistener
author_rank: Super Contributor
timestamp: November 07, 2021, 07:18:00 pm
content: it is possible to generate such a sweeping carrier, I was tried it for 145 MHz some time ago when played with si5351. But it was done for SSB modulation. For FM or AM you're needs to add modulator, mixer and filters.
Generate random numbers with changing range in verilog - Page 1
Forum section: electronics / beginners

author: yehudar
author_rank: Newbie
timestamp: February 25, 2015, 07:17:36 pm
content: (I'm sorry for my bad english)Hello!I want to generate random numbers in verilog, and the numbers should be from 1 to X. When X can change over time. The upper limit of X should be 10,000.The 'X' is a number that i'll get from another module (that is a problem for another day...).I started with building a LFSR (i'll put the code in the bottom) but right now the numbers can be from 1 to 2^14 and the range can't change, any ideas how to do that?Code:`timescale1ns/10ps`defineBD1//Basic Delaymodule lfsr(outputreg[13:0]random_num);reg[13:0]random_num;regClk;initialbeginrandom_num=14'b11111111111110;Clk=1'b0;endwirelinear_feedback;always#(`BD)Clk = ~Clk;assign#(`BD)linear_feedback =random_num^random_num^random_num^random_num;always@(Clk)begin#(`BD)random_num={random_num[12:0],linear_feedback};endendmoduleBest regards

author: katzohki
author_rank: Frequent Contributor
timestamp: February 25, 2015, 07:37:59 pm
content: Hmmmm... I guess you could mask the random number with your maximum. Get a new random number if it doesn't fall in your random range. That's probably not the best way.I found this, might be useful:http://rijndael.ece.vt.edu/schaum/slides/ddii/lecture6.pdf

author: LaurentR
author_rank: Frequent Contributor
timestamp: February 26, 2015, 12:20:22 am
content: Quote from: yehudar on February 25, 2015, 07:17:36 pmThe LFSR is a good start. Then it depends of the quality and quantity of random numbers you need.Note that if you need real random numbers (vs. pseudo-random), you'll have to feed your LFSR with a source of randomness (e.g. a few free-running toggle flops with different buffer lengths or something measuring an analog phenomenon). There is no limit to the search for random number quality.A good solution (but expensive) is to multiply the LFSR result by X and keep the MSBs (and add 1 if you really insist on getting from 1 to X). If you have substantially more bits in the LFSR than you have in X, the result will be fairly uniform. This solution is simple, has great throughput, but requires a full multiplier (big!). If you have more time and want to save area, you can code an iterative multiplier and that's probably as small as a good circuit will be.There are plenty of poor man's solutions after that. For instance, you can take the LFSR result, remove MSBs you don't need (above X), then throw away the result if it is >= X and pull another one. Easy to do, works well if you don't have a given throughput for your random numbers.

author: Kjelt
author_rank: Super Contributor
timestamp: February 26, 2015, 08:55:31 am
content: There is a list of "taps" for lfsr to use, for each bitsize you should use another lfsr, eg different taps.
Generate runt pulse. - Page 1
Forum section: electronics / beginners

author: perfect_disturbance
author_rank: Regular Contributor
timestamp: July 05, 2013, 07:22:51 pm
content: I was reading the users guide for the Rigol DG 4000 series function generators and trying to figure out how Dave generates the periodic runt pluses he uses to test refresh rate in some of his oscilloscope review videos. Does anyone here know how to do that?

author: AndyC_772
author_rank: Super Contributor
timestamp: July 05, 2013, 07:42:18 pm
content: Generate two streams of pulses with a microcontroller or CPLD, which are usually the same but occasionally differ. Join the two outputs together with a pair of resistors, and probe the point where they join.

author: jpb
author_rank: Super Contributor
timestamp: July 05, 2013, 08:51:44 pm
content: There are various scope testing boards that will do this - e.g. Rigols DS6000:http://www.batronix.com/pdf/Rigol/UserGuide/DS6000DemoBoard_UserGuide_EN.pdfotherwise arbs with a sequencing capability can do this easily (e.g. Agilent 33500 series or ones with a variable clock such as the Tabor WW5061).

author: perfect_disturbance
author_rank: Regular Contributor
timestamp: July 05, 2013, 09:18:38 pm
content: I thought he was doing this with a Rigol DG4000 series but apparently that's not the case. I guess I'll have to build my own.
Generate Three Channel PWM according to Analog pot, STM8S003F3 - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: August 26, 2020, 03:47:30 pm
content: 1. I am using STM8S003F3 MCU, and need to generate three channel PWM. When analog pot is 0V and zero PWM, and when pot is 5V then full PWM.2. Using TIM1 of MCU, which has max value of 65535 for period, and using its three channels, CH1,CH2,Ch33. Only need these three PWM pins, its inverted pins are not required, they are used for other purpose.. Below is code I have written in C, IAR, but when I check on DSO, I see nothing on pins, all zero, even if pot is 5V. Analog channel I am reading correctly.4. Also enabled AFRO in option bytes of IAR. Three pins of TIM1 used are:a) Pin 16; TIM1_CH1; PC6b) Pin 17; TIM1_CH2; PC7c) Pin 13; TIM1_CH3; PC3d) No inverted pins need to be changed, including CH4, all used for other I/O purposes.5. What I am doing wrong:a) On the fly, updating CCR1 values is ok? Or it can create issues?b) Any issue in configuration?Code:void pwm_with_adc(void){TIM1_DeInit();/* Time Base configuration *//*TIM1_Period = 65535UTIM1_Prescaler = 0TIM1_CounterMode = TIM1_COUNTERMODE_UPTIM1_RepetitionCounter = 0*/TIM1_TimeBaseInit(0, TIM1_COUNTERMODE_UP, 65535U , 0U);/* Channel 1, 2,3 Configuration in PWM mode *//*TIM1_OCMode = TIM1_OCMODE_PWM2TIM1_OutputState = TIM1_OUTPUTSTATE_ENABLETIM1_OutputNState = TIM1_OUTPUTNSTATE_ENABLETIM1_Pulse = CCR1_ValTIM1_OCPolarity = TIM1_OCPOLARITY_LOWTIM1_OCNPolarity = TIM1_OCNPOLARITY_HIGHTIM1_OCIdleState = TIM1_OCIDLESTATE_SETTIM1_OCNIdleState = TIM1_OCIDLESTATE_RESET*/TIM1_OC1Init(TIM1_OCMODE_PWM2, TIM1_OUTPUTSTATE_ENABLE, TIM1_OUTPUTNSTATE_DISABLE,ccr1_val, TIM1_OCPOLARITY_LOW, TIM1_OCNPOLARITY_LOW, TIM1_OCIDLESTATE_RESET,TIM1_OCNIDLESTATE_RESET);/*TIM1_Pulse = CCR2_Val*/TIM1_OC2Init(TIM1_OCMODE_PWM2, TIM1_OUTPUTSTATE_ENABLE, TIM1_OUTPUTNSTATE_DISABLE, ccr2_val,TIM1_OCPOLARITY_LOW, TIM1_OCNPOLARITY_LOW, TIM1_OCIDLESTATE_RESET,TIM1_OCNIDLESTATE_RESET);/*TIM1_Pulse = CCR3_Val*/TIM1_OC3Init(TIM1_OCMODE_PWM2, TIM1_OUTPUTSTATE_ENABLE, TIM1_OUTPUTNSTATE_DISABLE,ccr3_val, TIM1_OCPOLARITY_LOW, TIM1_OCNPOLARITY_LOW, TIM1_OCIDLESTATE_RESET,TIM1_OCNIDLESTATE_RESET);/* TIM1 counter enable */TIM1_Cmd(ENABLE);/* TIM1 Main Output Enable */TIM1_CtrlPWMOutputs(ENABLE);while(1){raw_adc = read_analog_channel(); /* 0 to 1023 */f32_ccr_val = (65535.0f/1023.0f)* ((f32_t)raw_adc);if(f32_ccr_val > 65535.0f){f32_ccr_val = 65535.0f;}else if(f32_ccr_val < 0.0f){f32_ccr_val = 0.0f;}u16_ccr_val = (u16_t)f32_ccr_val;ccr1_val = u16_ccr_val;ccr2_val = u16_ccr_val;ccr3_val = u16_ccr_val;TIM1_SetCompare1(ccr1_val);TIM1_SetCompare2(ccr2_val);TIM1_SetCompare3(ccr3_val);}}

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: August 27, 2020, 08:35:53 am
content: move up
generating 0.3V, 4Mz signal from microcontroller (ntsc / pal synch) - Page 1
Forum section: electronics / beginners

author: Jaunedeau
author_rank: Regular Contributor
timestamp: March 27, 2025, 02:20:54 pm
content: Hi,I want to output a csync signal to a SCART connector (75R terminated, csync only since color will be on RGB pins) from an stm32h450.I am very scare on space on the board and really would avoir using an opamp or active buffer.An obvious solution would be this :The line is terminated on each end with 75R, resulting in 37.5R, and with 3.3V output on the GPIO, the TV should see 3,3×37,5÷(350+37,5) = 0.31...V max, close enough. The MCU would see 385.5R and output about 8.5mA, that's ok.But I've been told it could be a good idea to add a diode like this :In this case, value of R6 is less critical : if the voltage goes above 0.3V, the diode would draw current, rise the voltage on R6 which will have a higher voltage drop, and the output voltage will be less sensitive to heat, psu, ...But looking at some diodes datasheet, if I take e.g. an SS26 diode, it seem hard to predict how much current it will draw at about 0.3V, something between 10 and 90mA... I do not understand how I am supposed to choose the resistor value.Should I use a diode for such a low current / tension or does this solution not apply here ? If I should, how should I choose the diode and resistor ?

author: wasedadoc
author_rank: Super Contributor
timestamp: March 27, 2025, 02:30:20 pm
content: The obvious solution is fine. No need for any diode. The 0.3 volt level is not at all critical.

author: eleguy
author_rank: Regular Contributor
timestamp: March 27, 2025, 03:39:06 pm
content: The output impedance of this divider would be ~62R which is out of spec (that is +-10%?). But maybe it is close enough. Also depends the length of the cable. Another thing to be considered is the rise time of the signal but that should not be problem in these speeds. One can always put a little cap in parallel of R6 if tuning is needed. I have not worked in the field of SCART signals. These are just thoughts that came to my mind.
Generating 3D Frame-packed HDMI output from two USB cameras - Page 1
Forum section: electronics / beginners

author: windsmurf
author_rank: Frequent Contributor
timestamp: September 12, 2019, 06:20:35 pm
content: I'd like to output 3D Frame-packed HDMI video to a 3D viewer that decodes this type of signal. I'd like the video source for this to be my two USB cameras.Does anyone know how this can be achieved?Thanks in advance!

author: amyk
author_rank: Super Contributor
timestamp: September 13, 2019, 11:49:10 am
content: How much do you know already? How much are you willing to learn?

author: windsmurf
author_rank: Frequent Contributor
timestamp: September 13, 2019, 11:50:01 pm
content: I don't know much in this area unfortunately. I'm definitely wanting to learn a lot moreI'm thinking a SideBySide video out might be the easiest way to get stereo vision realtime from two cameras... I can do this by just displaying two outputs in two windows... but is there a program that already does this for you within a single window? Working on this on Win10 now but also work with Ubuntu frequently.Thank you in advance!

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 14, 2019, 02:36:50 am
content: To program one yourself, you might start by looking atlibuvc(documentation). If you look at thesrc/test.cexample program, you'd need to open two devices, and two different src/test.c:cb() callback functions (to distinguish left/right frames).

author: windsmurf
author_rank: Frequent Contributor
timestamp: September 14, 2019, 07:42:34 am
content: Quote from: Nominal Animal on September 14, 2019, 02:36:50 amThank you for the suggestion. I'd played with pyuvc when I did a Deeplens project, but was hoping I wouldn't have to code for this.I'll check Github to see if someone's already done this.
Generating exact delay in us IAR-STM8 - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: December 16, 2014, 05:13:43 am
content: 1. I am using IAR for STM8 V1.42.2I have to generate some exact delay of us range like low as 25us to 100us.2. Clearly that can be done using timer. But I don't want to use timer for this purpose. I have 2 timer running for different purpose.3. I have used mplab & TI CCS. They have delay function which can generate exact delay like__delay_us() , __delay_ms , or __delay_cycles()is there any similiar function in IAR STM8?

author: TKt48
author_rank: Newbie
timestamp: December 16, 2014, 11:29:50 am
content: Delay functions, time functions usually use timers to work.Other method is to use asembler and "dumb" function executions. Knowing how much clock cycles they take to execute and clock frequency you can generate precise "delay". But it works only for short delays and to generate fast changing outputs.
generating gerber files with drill in altium - Page 1
Forum section: electronics / beginners

author: manubali
author_rank: Contributor
timestamp: June 14, 2017, 11:08:50 pm
content: hi, i am working on nixie clock project, i have finished pcb layout in altium and i have sent gerber files to manufacturer for quotation, i got reply that they need gerber files with drill instead of cam file, i am totally newbie with altium and pcb designing. so, can anyone tell me how do i generate them thanks.

author: Dave
author_rank: Super Contributor
timestamp: June 14, 2017, 11:57:35 pm
content: File -> Fabrication Outputs -> NC Drill FilesIt's going to generate a CAM file, out of which you need to export the drill gerber. The process is the same as for the other gerbers after that. The final result is a .txt file.

author: manubali
author_rank: Contributor
timestamp: June 16, 2017, 05:11:28 am
content: thanks everyone, waiting for pcb now.
Generating  PWM AC voltage with negative swing below the GND? - Page 1
Forum section: electronics / beginners

author: LinuxHata
author_rank: Frequent Contributor
timestamp: October 18, 2024, 08:45:01 am
content: Hello.I know, title is a bit misleading, but I simply don't know, which term applies to this correctly.Situation is as follows:I have +-5V supply "on board".I need to generate square pulses at output, at low frequency (50-200hz), but output should also go negative related to ground pin - output should swing from -2.5V to +2.5V. Current up to 5A.As far as I understand this, I need two mosfets, N and P channel, and have to drive them sequentially. For that I plan to use MCU with hardware PWM generator, with dead time and all bells and whistles.However, while with N mosfet everything is simple, I can't figure out, how to deliver negative voltage at P mosfet gate, from the MCU, which runs from +5 volts.Any ideas?(no transformers at input or output, please)

author: Andy Chee
author_rank: Super Contributor
timestamp: October 18, 2024, 11:02:57 am
content: Series coupling capacitor? Negative gate voltage charge pump?

author: johansen
author_rank: Super Contributor
timestamp: October 18, 2024, 09:08:26 pm
content: Find a high and low side gate driver with dead time, and an enable pin that can run on 10 volts (watch the undervoltage lock out level), and reference it to your -5v ground.For the signal inputs, a 2k resistor to -5 volts keeps both gates off... but your mcu is at +5 relative to ground, which means you need to subtract 5 volts from its signals.. using a 5.1v zener.you don't necessarily need an enable pin but you may want one that could be hardwired into a current sense resistor to turn the gates off.
Generating selectble clock speeds? - Page 1
Forum section: electronics / beginners

author: gmc
author_rank: Regular Contributor
timestamp: October 26, 2021, 08:56:37 am
content: I"m busy with a project where I would like to have a selectable clock speed of 1, 2, 4, 8MHz which is selected by a 4 way DIP switch.This will be used to drive a CPU which can then be tested as different speeds.Any suggestion on what would be the easiest approach. I was thinking of LM555 but then it has a max frequency on 2MHz and am not sure how I would even switch between the freq.I could go overboard and use a arduino but there must be a easier and simpler approach. Maybe some clock generator chip I'm unaware of?

author: oPossum
author_rank: Super Contributor
timestamp: October 26, 2021, 09:53:35 am
content: 16 MHz oscillator module and a 74HC161 or 74HC4040

author: gmc
author_rank: Regular Contributor
timestamp: October 26, 2021, 10:50:42 am
content: Thanks, great idea. Why didn't I think of that.On the ripple counter I can just connect the outputs via the dip switch

author: Ian.M
author_rank: Super Contributor
timestamp: October 26, 2021, 11:15:49 am
content: That's NOT a job for a regular DIP switch as any misconfiguration can short outputs together - either use a jumper, preferably five pin cruciform with the output from the center pin, but a 2x3 block with two commons in the middle for the output would also be reasonable, or use a four way switch, possibly a SMD slide switch.However, you seem to be going to a lot of trouble to avoid a MCU. Any low pin count PIC or AVR with CLKOUT and a runtime selectable clock divider can do the job *WITHOUT* running the clock signal through switches.

author: gmc
author_rank: Regular Contributor
timestamp: October 26, 2021, 11:37:20 am
content: Hmm, that's a another thing I didn't think about. If the user turns 2 or more outputs on then they will be shorted together.Maybe a jumper is better, but still not idiot proof. I"ll look into a low pin count MCU. Ideally this would probably be the most foolproof with a button to scroll through the frequencies

author: Zero999
author_rank: Super Contributor
timestamp: October 26, 2021, 02:36:46 pm
content: Quote from: gmc on October 26, 2021, 10:50:42 amHow about a multiplexer such as the 74HC4052? If you don't need two channels, put them in parallel to reduce the impedance.

author: Picuino
author_rank: Super Contributor
timestamp: October 26, 2021, 03:08:54 pm
content: Quote from: gmc on October 26, 2021, 11:37:20 amThere are tiny PICs that can do the job very well.I use the PIC16F15323 for doing a similar circuit. This PIC has four special modules called CLC (Configurable Logic Controller) which is programmable logic. For example you can make four divisors by two of an asynchronous signal.Edit:Of course, the CLC is programmable in execution time by the internal program in order to select the desired output.At last, you have a 16MHz oscillator, a divisor a multiplexer and a microcontroller to control them in one simple chip.
generator functions - Page 1
Forum section: electronics / beginners

author: dikkombe
author_rank: Newbie
timestamp: November 12, 2011, 06:36:15 am
content: hello people yesterday i was studying, and i saw on internet a function generator.what is a faction generator ??

author: Armin_Balija
author_rank: Regular Contributor
timestamp: November 12, 2011, 07:04:48 am
content: http://en.wikipedia.org/wiki/Function_generator

author: w2aew
author_rank: Super Contributor
timestamp: November 13, 2011, 03:48:44 am
content: Quote from: dikkombe on November 12, 2011, 06:36:15 amSimple answer: A function generator usually refers to a signal generator that can create sine waves, triangle waves, square waves and sawtooth waves (and more in most cases).
Generic 16x2 LCD unit - Page 1
Forum section: electronics / beginners

author: PerranOak
author_rank: Frequent Contributor
timestamp: December 18, 2021, 08:47:14 pm
content: I wonder if there is a good "user manual" for the standard LCD panel (16x2)?I bought one from Mouser but its datasheet just gives pinout and simple info. I want to know all about the codes that you send to it to render 4-bit mode and to control the various functions.Any help please?

author: retiredfeline
author_rank: Frequent Contributor
timestamp: December 18, 2021, 08:54:04 pm
content: Almost certainly they use the Hitachi HD44780 LCD controller or variant. You can easily find datasheets if you search on that.

author: Benta
author_rank: Super Contributor
timestamp: December 18, 2021, 08:56:35 pm
content: ^This.

author: pqass
author_rank: Super Contributor
timestamp: December 18, 2021, 09:12:13 pm
content: Here:https://www.sparkfun.com/datasheets/LCD/HD44780.pdfAlso, if you prefer an explanation and demonstration watch:

author: mariush
author_rank: Super Contributor
timestamp: December 18, 2021, 09:46:17 pm
content: Here's some more stuff that you may find useful ... see attachments belowA lot of these 2-4 line displays use clones of the hd44780 controller, which follow the same pinout, same commands, some have extra commands.Attached you'll find the SPLC780D and the ST7077U which are basically using the same commands, same pinout etc ...Also, New Haven Display (company that makes LCD displays) has a page that contains links to controller datasheets:https://www.newhavendisplay.com/datasheets.htmlYou may find the controller on your display listed there.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: December 19, 2021, 03:24:32 pm
content: First implement the 8-bit code.Later if you are confident the 4-bit code is easy.You need to save the second nibble and process that as first.You have to reset your LCD 3 times if i remember correct, so on restart it will be good.Dont use read mode ever, and use long delays first until your code is working to be sure.
Generic Comparator in LTSpice - Page 1
Forum section: electronics / beginners

author: Zero999
author_rank: Super Contributor
timestamp: March 27, 2023, 10:10:06 pm
content: Someone asked me about a generic comparator in SPICE, so I thought I would make a thread about it.The most obvious way is to use the generic op-amp as a comparator. If the output voltage is to be limited to the supply rails, then the level2 model is required, otherwise the output will swing to extreme voltages, as the model is deigned to be used with negative feedback, which will inherently limit the voltage.A less obvious solution is to use the diffschmtbuf model, which is in the  section. It enables the high and low resistances and voltages to be configured to simulate an open-collector, or push-pull output. It also has adjustable hysteresis, which is handy, as many real comparators have a fixed hysteresis.I did include the simplest open-collector I can think of, which is simply a behavioural resistor, which changes its value from 1T Ohm, to 1 Ohm, when the voltage on the non-inverting input is below the inverting input.1 = NON-INVERTING INPUT2 = INVERTING INPUT3 = POSITIVE POWER, which isn't used.4 = NEGATIVE POWER, the point one side of the behavioural resistor is connected to.5 = OPEN COLLECTOR OUTPUT, the other side of the resistor..SUBCKT Comparator 1 2 3 4 5RComp 4 5 R = {if(V(1)<V(2),1,1T)} ;Behavioural resistor..ends ComparatorI know there are more accurate ways to model a comparator. I just posted the simplest one, as it was for an LTSpice beginner.It also demonstrates how to use a net list to put voltages in a schematic, without drawing them.For example the following line creates a voltage source called psu, which is connected between 0V and +V and has a DC voltage of 5V.Vpsu +V 0 5V