hybridfree/eevblog-posts huggingface dataset:
Specifying Device Bandwidth using Overcompensation Technique - Page 1
Forum section: electronics / projects

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 20, 2012, 08:50:35 pm
content: i have a measurement device (differential probe actually) that i want to specify its bandwidth, it has simple RC low pass filter to compensate. as can be seen in the first picture is its bode profile, the normal look and way. base on its -3db attenuation, it can be specified as 20MHz device. now at the second picture, overcompensating a bit, 2dB peak (still under |3dB| envelop) and then going down at -3dB its 40MHz. i think i can even further overcompensate it for 3dB peaking and probably 50MHz at -3dB. and specify the device as 50MHz BW? based on its -3dB profile.so what i want to ask, is it wise to specify the device using the second picture (overcompensated)? is it normal practice in engineering world? or is a bollock, we should use the 1st picture? thanks.

author: krivx
author_rank: Frequent Contributor
timestamp: May 21, 2012, 01:13:11 pm
content: Any measurement is suspect unless you specify how you made it.I would call that a 20Mhz -3dB with a ~+-0.2dB variation in the passband/flat region (1st image), or a 40MHz -3dB point with +-2dB variation (2nd image). Personally I would prefer to have the probe in the first image, and know I can trust it's measurements.

author: ejeffrey
author_rank: Super Contributor
timestamp: May 21, 2012, 01:32:23 pm
content: For an oscilloscope probe the more important criteria are in the time domain -- namely overshoot, ringing, and settling time. Plot the step response function and see if it is something you would be willing to use.If you want to stress it even more, look at a 17 MHz square wave. The ringing of the rising edge will not have damped and will be 'in phase' with the following falling edge (in frequency domain, the third harmonic will be resonant with the filter).Generally for scope probes you prefer fast settling time with minimal overshoot to maximum 3 dB bandwidth.

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 21, 2012, 11:27:39 pm
content: thanks jeff for the idea. it may be off topic bu a valid point. i believe i still stuggling with ringing or reflection when f >= 10MHz (square and some sine wave). i'll try to get a snap shot when i got home. and thanks krivx for your advice.
Spec'ing and switching a mains powered relay? - Page 1
Forum section: electronics / projects

author: Northy
author_rank: Regular Contributor
timestamp: January 19, 2021, 10:16:24 am
content: Hi all,I'm building a DIY box with some pretty serious amp modules in it.There will be two modules, with the spec:100-240 V AC, 50-60HzAC Current Avg / Short Term: Nominal 4A / Max 25AInrush Current (230 V AC): 41A peakI'd like a nice on/off switch on the front of the box.I had a quick look (even though I imagined something wouldn't exist) for a power switch rated high enough and I couldn't see anything rated high enough for 2 x the above specs, or anything that really looked 'nice' at high current ratings.So I had the idea of using a big relay?I've never had to spec a relay to switch mains before, how much should it be over-rated for reliability?Is there a pretty standard way to enable the relay that would allow the box to be turned fully off (0W power use), when it's off?Could the mains be switched through a low power, nice looking switch to enable the high power relay that would power up the modules?Thanks,G

author: Terry Bites
author_rank: Super Contributor
timestamp: January 19, 2021, 11:06:52 am
content: Mains SS Relays generate a lot of hash.Mechanical with mains coil will buzz a littleHow are you going to control your relay AC/DC LV, Mains?There's no cheap way. Use a contactor and put poles in parallel- with snubber!If you don't use a snubber you are going to severely shorten the contact life.https://www.tlc-direct.co.uk/Products/CMREL230slash25slash40.htmlhttps://components.omron.com/relay-basics/general-app

author: Northy
author_rank: Regular Contributor
timestamp: January 19, 2021, 02:18:28 pm
content: I hadn't worked out how I was going to control the relay yet, I was wondering if there was a way to do it where the unit would truly use zero power when switched off, so by enabling the relay with mains through a lower rated switch on the front panel?Is that possible?What sort of snubber would you suggest?Thanks,G

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 19, 2021, 02:28:04 pm
content: Could use a DC relay with a capacitive power supply to run the coil.If you can modify or slightly redesign the power supply, you could have the switch disconnect the startup resistor and signal the controller to turn off the output?

author: Northy
author_rank: Regular Contributor
timestamp: January 19, 2021, 03:09:17 pm
content: Quote from: NiHaoMike on January 19, 2021, 02:28:04 pmDo you mean by putting the modules into a low power/sleep mode?Unfortunately they still use significant power in that mode and my conscience would rather a true zero power off - we've got to be green these days haven't we?Thanks,G
Spec'ing differential pairs in CAD software - Page 1
Forum section: electronics / projects

author: Northy
author_rank: Regular Contributor
timestamp: October 22, 2020, 03:06:18 pm
content: Hi all,Although I'm working in Eagle, I thought this was more of a generic question. If it's not in the correct place, then I'm sorry.How do people convey their differential pairs and controlled impedance trace requirements to their board manufacturer?I've gone with a specific width/spacing for the matched pairs and added text notes to the files at the moment, to allow the manufacturer to adjust them.Is this a good way to do it?The thing I'm worried about is the software adjusting the track widths when I create the gerbers. Can software do any sort of track width consolidation? Are there some settings I should be looking at?Thanks,G

author: Northy
author_rank: Regular Contributor
timestamp: November 11, 2020, 01:22:03 pm
content: Incase this helps anyone in the future I just added the following note to the gerber files and the PCB purchasing spec, and the PCB manufacturer will adjust them to suit:Note per controlled impedance (differential signal traces):- Top Layer, 9mil wide/5mil gap to be 100 Ohm- Top Layer, 7mil wide/5mil gap to be 90 Ohm

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: November 11, 2020, 05:47:26 pm
content: Typically it's done on the fab drawing. You call out the data like you did, and add any other special instructions.I also add a readme.txt file to the fabrication package that describes the stackup, the function of each layer, and repeats the special instructions. But make sure they expect it, otherwise it may slow down and confuse the process rather than help.It's weird that it's still done this way. There are other ways to send manufacturing info to a manufacturer, like ODB++, and some other formats I forget, but every time I asked I was told that plain Gerber/NC/text files are good enough!And that was even for 24+ layers, mixed materials, blind and buried vias, etcSo to answer your question, yes, that's a good way to do it!

author: Northy
author_rank: Regular Contributor
timestamp: November 11, 2020, 06:10:13 pm
content: Thanks for the reply.I've added it to the documentation layer of Eagle, then I spit out a Notes.gbr from that layer.I also create a PCB purchasing spec document for each PCB (for quality/safety) and I've added it to that too.Thanks,G

author: nctnico
author_rank: Super Contributor
timestamp: November 12, 2020, 02:35:22 pm
content: Quote from: Northy on October 22, 2020, 03:06:18 pmWell, you don't. You specify the board stack-up (copper thickness, dielectric material type & thickness) or select an existing stackup and use that to calculate the trace widths / distances. A board manufacturer doesn't care about your design / trace widths. Their only job is to fabricate a board within the given mechanical tolerances.IOW: the trace widths and distances are to be calculated during the PCB design stage and stay fixed from there on. This does require planning.
Specs for EC5 high-current connectors? - Page 1
Forum section: electronics / projects

author: iXod
author_rank: Frequent Contributor
timestamp: January 02, 2019, 07:04:55 am
content: I can see EC5 connectors everywhere but not a single drawing or spec sheet.Anybody have measurements on the individual plug/receptacle and pair spacing?Thanks,iX

author: beanflying
author_rank: Super Contributor
timestamp: January 02, 2019, 07:20:13 am
content: Personally not a fan. They were released by Eflite/Horizon Hobbies (EC3 & 5) some years ago to try and lock customers to their chargers batteries etc. You might try trawling RC Groups but I have never seen the dimensions anywhere including when I was selling some gear based on them.I did a quick search and I didn't turn up anything. Might be time to break out the verniers

author: iXod
author_rank: Frequent Contributor
timestamp: January 02, 2019, 08:07:55 am
content: What good will a vernier do me? I’ll then know what size I have, to then compare against... what specs/dimensions on-line?iX

author: beanflying
author_rank: Super Contributor
timestamp: January 02, 2019, 08:13:56 am
content: You asked for a drawing so I have assumed you actually wanted the dimensions as there most likely isn't any you will need to measure yours?Edit found a set but not Horizon Hobbies so the dimensions may not be rightIf you wanted contact resistance figures then I very much doubt you will find them. These are built down to a price and no one seriously pulling 100A + would generally use them.
Specs for Hammond NSQ4008? - Page 1
Forum section: electronics / projects

author: basinstreetdesign
author_rank: Frequent Contributor
timestamp: July 01, 2018, 02:54:44 am
content: Hi, I'm trying to measure low-level distortions on my HP 3580A spec. analyzer. However, when I connect it to any other piece of gear on my bench I get significant amounts of 60 Hz power line harmonics mixed in with the test signal. This can happen when connected to any of several other bits of gear such as my Tek465, my cheap Fluke counter or the UUT. I think it's the result of a ground loop around all of those pieces of gear. The 3580A was marketed with a transformer input as OPT 2 but mine doesn't have it. I want to break the loop but still measure my signal. So I am planning on putting an audio transformer on the front connector of the 3580A. I want to use the one pictured below, a Hammond NSQ4008, but I cannot find a pinout or any specs no matter where I look. I want to use this one because:a) I have it,b) it's renowned for fairly good quality,c) it's not huge andd) I have it.Does anybody have any tech info on this transformer?
Spectra EEL Evans Electroselenium 400-700nm analyzer teardown - Page 1
Forum section: electronics / projects

author: oz2cpu
author_rank: Frequent Contributor
timestamp: November 03, 2022, 08:55:54 am
content: Spectra EEL Evans Electroselenium 400-700nm analyzer teardownvery old laboratory Spectroscopy instrument, can compare 4 samples, measure peaks and levels between 400-700nm, a little clean and adjust and it really works, i also checked its calibration for wavelength is still amazing, also contain really nice mechanics and optics. if anyone know when this unit was designed or made ? please comment ?https://youtu.be/A8MUS-4Yxh8

author: Kleinstein
author_rank: Super Contributor
timestamp: November 03, 2022, 11:29:25 am
content: It is hard to tell when the design was made. The core part is the gradient filter to make a relatively simple spectrometer with good intensity. Such filters are still quite expensive.As there is not much else setting the wavelength it is not such a surprize to wavelength calibration is still OK. It it anyway not really high resolution, but probably OK for the task.The large Aluminium casting looks somewhat new - so more like late 50s or early 60s.The transformer is a kind of special voltage stabilizing one. This is also why it is relatively large for the not that high power rating. The capacitor is likely part of the voltage stabilization.The fine shaddow for the read out is from a kind of fine wire on the back of the optics. It is visible in the video.The lamp can be a bit tricky. To get good intensity also in the beep blue range it needs to run relatively hot and may thus have a limited lifetime (e.g. less than 500 h).

author: oz2cpu
author_rank: Frequent Contributor
timestamp: November 03, 2022, 12:28:02 pm
content: thanks for your comments,yes the filter is super nice and special, and ofcourse still very accuratei also seen the video after i made it, and NOW i see where the thin line is coming from :-)great that was shown in the video.the lamp is working, luckyand it is looking like brand new, no dark spots or anything like that,it does look special in its filament design too,so i assume people turned this unit off right after each use,since i own a much more modern spectrometer with just a few nm in resolution,i really dont need to keep this old one for any practical experiments,so i need to think now what to do with it :-)
Spectre : Invalid component name was given as value of parameter - Page 1
Forum section: electronics / projects

author: promach
author_rank: Frequent Contributor
timestamp: June 16, 2021, 03:50:08 am
content: Forhttps://github.com/promach/AC_analysis_methods/tree/main/GNT, why spectre throws me the following error ?

author: evac
author_rank: Contributor
timestamp: June 16, 2021, 10:48:11 am
content: From the log it looks like it could be a syntax error, but without seeing the netlist it's difficult to tell what the actual issue is.The GNT github page also mentions you should use "Any reasonably recent MMSIM version.", which I'm not sure MMSIM 15.1 qualifies as since it's ~6 years old, so perhaps some constructs not supported by legacy versions are being used.EDIT: Just noticed that the getting started document is dated 2015 so I guess it's unlikely to be an issue with using an "old" version of Spectre.

author: promach
author_rank: Frequent Contributor
timestamp: June 16, 2021, 12:10:18 pm
content: Solved: Seehttps://community.cadence.com/cadence_technology_forums/f/custom-ic-design/48241/spectre-invalid-component-name-was-given-as-value-of-parameter/1376102However, I am getting entirely different and strange (the opamp seems not working at all) simulation waveform as compared to the waveform onpage 12 of getting_started.pdf
Spectroscopy-like digitizing system - principle of working - Page 1
Forum section: electronics / projects

author: ricko_uk
author_rank: Super Contributor
timestamp: November 23, 2021, 05:46:59 pm
content: Hi,I am looking to understand a spectroscopy-like system principle based on magnetic fields.With reference to the attached picture, there is a vertical stackup comprising a coil, a sample of a material or substance above it and on top a "receiver" that can read the magnetic field amplitude.The substance has its own electromagnetic spectrum unique to it.Assuming a number of different frequencies are applied (either at the same time or sequentially) and the coil's magnetic field flows through the substance and reaches the receiver sensor will the receive:1) the same spectrum "shape" of the sample or2) its inverse or3) something else?In other words, for every "peak" frequency of the sample, will the received read a peak or a valley?What about at the resonant frequency? Will the sample absorb more magnetic field energy or none and let it through?The above is obviously assuming an ideal scenario with on ideal conditions. In practice what would the issues that come into play?Thank you
Spectrum analyser for pre-compliance checks - Page 1
Forum section: electronics / projects

author: ricko_uk
author_rank: Super Contributor
timestamp: June 23, 2022, 07:19:53 pm
content: Hi,I was looking at an entry level spectrum analyser to see where on a PCB there might be high emissions.The maximum frequency I ever need to test to (for the work I do) is 1GHz. So I am thinking about the DSA815 and DSA815-TG (the first two in the table):https://www.rigol-uk.co.uk/products/spectrum-analysers/rigol-dsa800-series/Is that a good choice? Or perhaps there are better ones for in that price range?How/what is the tracking generator used for?Thank you

author: jonpaul
author_rank: Super Contributor
timestamp: June 24, 2022, 06:40:54 am
content: Buongiorno Signore the 1 gHz Chinese SA may not be needed....Rather then measure and then patch up a poor design and layout after the fact.easier to learn good PCB layout and shielding practice for EMI compliance and design the PCB from the start,Just a scope and DIY loop probes can see the EMI. Conducted 100/150 kHz...30 MHz, radiated depends on the device class and power.Actual compliance and qualification of a device needs an extensive lab for both conducted and radiated EMI.Finally any SA will have a learning curve.CiaoJon

author: Karel
author_rank: Super Contributor
timestamp: June 24, 2022, 06:58:03 am
content: Imho it's almost impossible to do pre-compliance measurements without a (semi-)anechoic chamber and an (expensive)calibrated antenna. I have used a temcell but the results are not comparable because the antenna needs to be locatedat least 3 meters away from the device under test.In the end we decided to do the pre-compliance tests in a certified lab. Usually you can rent it for half a day.They give you a printed report but no certificate (in order to get the lowest price).A spectrumanalyzer is useful if you need to find the source of a problem. A tracking generator is not needed at all.

author: ricko_uk
author_rank: Super Contributor
timestamp: June 24, 2022, 01:00:47 pm
content: Thank you both
Spectrum Analyzer and RF burst... - Page 1
Forum section: electronics / projects

author: SM6FIE
author_rank: Newbie
timestamp: February 19, 2023, 10:24:12 pm
content: Does anybody know or have any idea about how short RF emissions (burst) it is possible to detect with a HP8593E (or more generally with a heterodyne Spectrum Analyzer) configured to “MAX HOLD” mode. We assume that the RF burst is emitted within the passband of the SA. Is it possible to detect a 1, 10, 100 uS RF burst? I do understand that this question is very broad; I’m just interested in some sort of ballpark figure guide lines.

author: oz2cpu
author_rank: Frequent Contributor
timestamp: February 20, 2023, 05:31:51 pm
content: yes i got an idea : NO !you can not detect short pulses with a normal sweeped analyzeryou need too many sweeps to add all the tiny fractions of the signals, if / when you ever hit a sweep while the pulse is at correct frequencyis it a hopping transmitter you want to decode ?or is it a fixed frequency ? you want to see the modulations ?the last is easy : use zero span mode, then your X line become a time scope, where you can use the time pr div to show the modulationyou can even trig like a scope.you can also make a diode peak detector,and then a scope

author: pdenisowski
author_rank: Super Contributor
timestamp: February 21, 2023, 03:08:05 pm
content: That's a complicated question: for swept spectrum analyzers, it's going to be largely a function of sweep speed / resolution bandwidth, although this is always a probabilistic situation. It's certainlypossiblethat you might catch a 1 uS event (if your RBW just happened to be on the right frequency at the right time), but it might not be verylikely.Most people only discuss POI (probability of intercept) in the context of FFT-based (realtime) analyzers. Since I don't have my own video (yet!) on this topic, I'd suggest this one:https://ieeetv.ieee.org/micro-apps-2013-understanding-probability-of-intercept-for-intermittent-signalsAn HP85xx series analyzer (or similar) is not what I would use if I were trying toreliablydetect a 1-100 us burst.
Spectrum Analyzer Input Protection Project (HP 3588A) - Page 1
Forum section: electronics / projects

author: Smoky
author_rank: Frequent Contributor
timestamp: January 27, 2024, 03:23:17 am
content: I put together two spectrum analyzer protection devices based on Paul Carlson's SA Protection Circuit on Youtube. One is for the input and one is for the output of a 3588A.The protection devices are going to be used for the same purpose that Paul uses his (aligning old radios with high voltage present) except I built mine with different parts:My HP 3588A has a 50 Ohm output so a resistor was put to ground in one of them:I set the Spectrum Analyzer's source output to -10dBm with a full frequency span from 10Hz to 150MHz. The input was set to 1Mohm:Since I'll be using these devices for aligning radios around the 455KHz range, I set the start frequency to 355KHz and the stop frequency to 555KHz. It turned out to be completely flat (+/- .01dB) across 200KHz
Text to speech project on microcontroller - Page 1
Forum section: electronics / projects

author: Karamel
author_rank: Regular Contributor
timestamp: November 14, 2016, 06:29:44 pm
content: Hi,I am, currently, taking signals and system couse. So, I want to do this project in next summer with stm32f407 discovery board. (this is exactly hobby project)Okay.- I can use fourier transform for generating sound. Because, fourier solution takes too less memory in rom.- I can find all coefficents of sounds for all alphabet but, is it enough?For example, "Hello"word says like that "Hel-lo". However, it is not reads like that "H-e-l-l-o". Also alphabeth writes diferent, reads different when there are more letters nearly between eachother. If I must work like syllable by syllable So, there could be too much sound and their datum of coefficent.(it takes in too much space inside rom and I guess, it will not be enough?)I am confused. Where should I start to research? Now, I have a billion of stupid questions inside my headBest Regards,Karamel

author: kevyk
author_rank: Contributor
timestamp: November 14, 2016, 07:04:10 pm
content: I worked on the first speech synthesizers back in the 80's and back then, and I think still now, the way quality speech synthesis was accomplished was to store the transitions from phoneme to phoneme (many hundred for English). That will produce a much more natural sound than storing the spectra (or raw signal) of each phoneme itself then trying to string them together. You can experiment by doing it in time domain first.Search the patent database for speech synthesizers to get some ideas.

author: janoc
author_rank: Super Contributor
timestamp: November 15, 2016, 12:17:24 am
content: Quote from: Karamel on November 14, 2016, 06:29:44 pmNo, it isn't enough.BTW, to avoid confusion, you may want to change the title - it istext to speech, not speech to text what you are attempting, if I understand correctly. Speech to text is speech recognition, I doubt you would be able to make that work on a microcontroller beyond a few hardcoded words.Now to synthesize speech for a given language you should not work with FFT and individual letters, exactly because they are not pronounced the same as they are written. So stringing together sounds of individual letters would not do any good.Commercial synthesizers usephonemes- all sounds that are used in the given language. Then each word is encoded using these, typically using some rules and/or a large dictionary for all the exceptions.Look up something called "formant synthesis" - this is the approach that has been used e.g. by the Speak & Spell toy. Good starting point for research could be even this Wikipedia page:https://en.wikipedia.org/wiki/Speech_synthesis
Speed and direction controller for PSC motors - Page 1
Forum section: electronics / projects

author: StefanHamminga
author_rank: Contributor
timestamp: October 02, 2016, 12:09:07 pm
content: For a project I'm working on I need to control two 230 VAC permanent split capacitor motors (500W each). I need to be able to change direction and speed using an MCU (3.3 VIO). The controller needs to be relatively inexpensive to make in small series (1 to 20) and have some headroom to handle larger motor types.I did a design (see schematic picture), but so far most of my experience has been DC / low voltage. I'd love to have some critique / feedback on my initial design.
Speed Sensor Simulation - Page 1
Forum section: electronics / projects

author: yoda_bear
author_rank: Contributor
timestamp: May 12, 2017, 04:47:58 pm
content: So I purchased a Siglent 2042X function generator to simulate a vehicle speed sensor being connected to an ECM. I noticed my function generator didn't come with any probes, I should have known better. That said, where can I purchase some probes or is it easier to build your own?Just looking for advice from someone who has been in my position.Thanks.

author: james_s
author_rank: Super Contributor
timestamp: May 12, 2017, 05:42:31 pm
content: Function generators are not normally used with probes. I have a cable with a couple of grabber clips on the end that I use with mine, and I occasionally make up a custom cable.

author: yoda_bear
author_rank: Contributor
timestamp: May 12, 2017, 06:04:10 pm
content: Sorry bad choice of words there.

author: Rerouter
author_rank: Super Contributor
timestamp: May 12, 2017, 09:24:25 pm
content: There are 3 main types of signal types that are likely to be fed to an ecu, first is hall effect, this is an open collector npn transistor with a limited collector current, generally 5mA max load. This type assumes pullup for npn or pulldown for pnp. Generally 10-22k, this type can be approximated to a signal gen biased above 0v with a diode pointing towards the generator.Next up is totem pole, this is still transistors. 0.3/0.7v to 1v less than sender.supply, generally 500uA loading, this is essentially the same as the first without the diode.And finally is inductive, this is a high impedance current mode differential signal, and its amplitude begins very small for small signals 50-70mV for 1kmph, getting up to 400mv around 10kmph, and peaking at around 2.8v at 120kmph, if you just want to feed in an input then set it for about 2.5v or 5v pk-pk, 0v centered.There are some others like coil and points but i doubt that would be fed to an ecu.If in doubt begin with inductive.
SPI communication issue with LAN9252 on custom PCB (Raspberry Pi Zero W) - Page 1
Forum section: electronics / projects

author: Wimbledon013
author_rank: Newbie
timestamp: July 07, 2025, 09:10:59 am
content: Hi all,I'm working on a custom PCB that integrates a Raspberry Pi Zero W and a LAN9252 chip for EtherCAT communication.To start, we successfully tested the setup using an EasyCAT PRO board connected to the Raspberry Pi Zero W — both EtherCAT and SPI communication worked as expected.Based on that, we designed a custom PCB where the Raspberry Pi Zero W plugs in, and the LAN9252 is on the base board. However, with this setup, SPI communication fails:We see SPI signals (MOSI, SCK, CS) reaching the LAN9252 (verified with measurements).The LAN9252 does not respond on MISO — it's as if the chip is not replying.The LAN9252 clock pins (pins 1 and 2) show a 25 MHz clock signal, as expected.We designed the board following the EasyCAT PRO and Microchip LAN9252 reference designs:EasyCAT PRO:https://www.bausano.net/images/arduino-easycat-pro/EASYCAT_PRO_160726.pdfLAN9252 reference:https://ww1.microchip.com/downloads/en/DeviceDoc/LAN9252.SPI.SQI+GPIO16.Mode.Rev.A.pdfWhat I’ve checked so far:SPI lines reach the LAN9252 (scope verified)25 MHz clock present on pins 1 and 2Supply voltages OKWhat else should I check to diagnose this no-response situation?I’ve attached the schematic for reference. Any help or suggestions would be greatly appreciated!

author: Roehrenonkel
author_rank: Frequent Contributor
timestamp: July 07, 2025, 10:04:49 am
content: Hi,MISO = Master In Slave OutMOSI = Master Out Slave In.

author: voltsandjolts
author_rank: Unknown
timestamp: July 07, 2025, 10:14:28 am
content: The LAN9252 datasheet has a lot of info in the SPI section, worth a close read. I noted this:Quote

author: Wimbledon013
author_rank: Newbie
timestamp: July 07, 2025, 11:17:50 am
content: I run the EtherCAT app manually from the Raspberry Pi, so there is a significant amount of time between power-up and starting SPI communication.I use the same app with the EasyCAT PRO, and with that setup, it works.Additionally, try switching the MOSI and MISO, but this also didn't work.

author: sd
author_rank: Unknown
timestamp: July 07, 2025, 11:14:45 pm
content: Maybe don't leave the RST# pin floating?

author: Wimbledon013
author_rank: Newbie
timestamp: July 08, 2025, 06:24:56 am
content: If I look at the datasheet, it doesn't need it.". Thus thissignal may be left unconnected if an external hardware reset is not needed."

author: sd
author_rank: Unknown
timestamp: July 08, 2025, 09:40:58 pm
content: The reference design has a pull-up and cap, maybe it's worth a shot.Is the EEPROM programmed?

author: Wimbledon013
author_rank: Newbie
timestamp: July 10, 2025, 04:30:38 pm
content: I have found the problem 1 one was the mode pins where not correctly configurate both should have the led to the ground. The other one is that to get the spi working you first should programma the EEPROM.
SPI EEPROM - polling status register for WIP/RDY - Page 1
Forum section: electronics / projects

author: HwAoRrDk
author_rank: Super Contributor
timestamp: June 12, 2019, 12:04:07 am
content: I'm currently writing some MCU code that interfaces with an external SPI EEPROM, but am unsure whether a method I would like to use is widely supported by all EEPROM manufacturers.Using the RDSR command, the status register can be read to determine whether there is a write still in progress by looking at the WIP (a.k.a. RDY) bit. The datasheet for the particular EEPROM chip I'm using from ST (an M95256) says that the status register can be repeatedly read by continually clocking bytes out - that is, you can continuously read the status over-and-over as many times as you like in one SPI transaction.Does anyone know whether EEPROMs from other manufacturers support this method of polling the status register? I have looked at datasheets for equivalent chips from Microchip (25AA256), Atmel (AT25256B) and ON Semi (CAT25256), but I can't see any explicit mention of whether this is supported.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: June 12, 2019, 08:28:57 am
content: afaik from my few projects using SPI eeproms (25LC640) it's the same; I didn't check now if bit positions are the same, but at least all is named the same way.

author: HwAoRrDk
author_rank: Super Contributor
timestamp: June 12, 2019, 03:29:29 pm
content: Yes, the bit positions and meaning all seem to be standard; I have no concern there. Just whether continuous clocking out of the status register is supported by all manufacturers.Wish I had the foresight to buy a variety of parts from various manufacturers so I could test for myself.

author: HwAoRrDk
author_rank: Super Contributor
timestamp: June 12, 2019, 04:56:46 pm
content: I have been reading some app notes from various manufacturers (Microchip, Atmel, ISSI) and they all implicitly show - in flow diagrams or example code - a full SPI transaction cycle (toggling CS, issuing RDSR command, etc) for polling the status register.This seems... needlessly inefficient. Surely it can't be just ST EEPROMs that facilitate polling by continuous clocking, can it?

author: HwAoRrDk
author_rank: Super Contributor
timestamp: June 12, 2019, 06:40:33 pm
content: Well, I think I found my own answer. In ST application note AN2014, they state:QuoteSo, one must conclude that the latter behaviour is not supported by many (or all) other manufacturers.It would be nice if other manufacturers explicitly said so in their datasheets or app notes, but they don't.
solved - Page 1
Forum section: electronics / projects

author: incf
author_rank: Frequent Contributor
timestamp: June 07, 2025, 12:48:03 pm
content: edit: solved, it was a test artifact, the erase command was so slow that the MCU went to sleep before the last command finished.old title: "SPI flash appears ignoring "Deep Power Down" 0xB9 command only after erase?"I've got a Winbond W25Q32  SPI flash IC on a battery powered PCB.These flash ICs have a special "Deep Power Down" (0xB9) command.On this particular board when the flash is in "deep power down mode" the whole system consumes 6uA and if I don't send "deep power down" commands the system consumes 11uA.For some reason after performing an erase command, it appears as if the flash loses the ability to enter "deep power down" mode.Below are some of the simplest test cases I've found to demonstrate the issue. The observed system current consumption is listed at the start of each line below:6uA: Power up the flash (0xAB). Read its unique ID. Power Down the flash (0xB9).11uA: Power up the flash (0xAB). Read its unique ID. (do not power down the flash)6uA: Power up the flash (0xAB). Power Down the Flash (0xB9)6uA: Power up the flash (0xAB). Read a page of data. Power Down the Flash (0xB9)6uA: Power up the flash (0xAB). Send page program command with some data (but don't erase before). Read a page of data. Power Down the Flash (0xB9)11uA: Power up the flash (0xAB). Erase a sector. Write/Program one or more pages of data. Read a page of data. Power Down the Flash (0xB9)11uA: Power up the flash (0xAB). Erase a sector. Power Down the Flash (0xB9)11uA: Power up the flash (0xAB). Erase a sector. (do not power down the flash)*actual command sequences can include commands I refer to as "Enable Reset" "Reset" "Enable Write" "Read Status Register." Adding "Enable Reset" "Reset" before power down makes no difference.**reading and writing a page of data after erasing makes no difference either***adding a delay makes no difference either. And CS is in fact highDoes anyone have any ideas about what might be occurring?In theory, the act of erasing could alter the deep sleep current. It is technically operating within it published limits. But I find that unlikely.What seems more likely is that there might be some quirk in the command set / flash IC internal state machine that I am not recognizing.https://www.winbond.com/hq/product/code-storage-flash-memory/serial-nor-flash/?__locale=en&partNo=W25Q32JVhttps://www.winbond.com/hq/support/documentation/downloadV2022.jsp?__locale=en&xmlPath=/support/resources/.content/item/DA00-W25Q32JV_1.html&level=1https://www.gigadevice.com.cn/Public/Uploads/uploadfile/files/20220714/DS-00088-GD25Q32C-Rev4.1.pdfhttps://www.renesas.com/en/document/dst/at25sf321b-datasheet?r=1608806
SPI Flash Memory Audio File Write and Play - Page 1
Forum section: electronics / projects

author: gevv
author_rank: Contributor
timestamp: November 11, 2022, 10:26:08 am
content: Hi, Flash IC is an audio file playback circuit PIC16F628A 25Q32 prepared for high-capacity spi flash memory ICs known as Bios IC.https://youtu.be/uJ1pkgnqAI400:07 General circuit description01:27 Circuit diagram01:32 PCB drawing01:37 Test 1 Canary voice02:22 Test 2 Nightingale voice03:15 The module I use to load the Flash IC03:45 Converting audio file07:07 Notes
SPI Mode Selection of CS5364 . - Page 1
Forum section: electronics / projects

author: electronx
author_rank: Regular Contributor
timestamp: June 14, 2024, 06:19:07 pm
content: Im trying to determine SPI mode of CS5364 .In datasheet saying "CDOUT is the output data line to a controller. Data is clocked in on the rising edge of CCLK and is supplied on the falling edge of CCLK."What exactly happens to CPOL AND CPHA in this case?
SPI MPL115A barometer interfacing. - Page 1
Forum section: electronics / projects

author: kiran_shrestha
author_rank: Regular Contributor
timestamp: September 06, 2014, 10:57:01 am
content: I have been working on a project. Its interfacing MPL115A SPI barometer. I have succesfully interfaced the MEMS IC to my controller. But I am unable to get the actual data cos i am unable to get the real coefficient value from the SPI registers.Here's the description of the circuit I have made.http://shortedwire.blogspot.com/2014/08/mlp-barometer-sensor-design-with-sdi.html

author: janekm
author_rank: Unknown
timestamp: September 06, 2014, 09:08:52 pm
content: Could you give a little more detail on what problem you are encountering? You say that you "successfully interfaced" the IC to your MCU, suggesting that you did manage to communicate with it? How did you confirm this if you aren't able to read the coefficients?Have you read this app note:http://cache.freescale.com/files/sensors/doc/app_note/AN3785.pdf? Have you verified your signals on a logic analyser against those given in the app note & data sheet?

author: kiran_shrestha
author_rank: Regular Contributor
timestamp: September 08, 2014, 04:34:54 am
content: Thanks for reply ,, I actually solved my problem. I was unable to convert the hex value to the floating value coefficients but it's ok now.
Spice analysis of feedback stability - Page 1
Forum section: electronics / projects

author: TimFox
author_rank: Super Contributor
timestamp: January 08, 2016, 09:24:22 pm
content: I remember the existence of a trick, suitable for Spice analysis, that gives the (complex) loop gain function without breaking the feedback loop. As I remember, it involved inserting the independent generator into a node within the loop and computing an appropriate result.Does anyone have the trick or a link to a discussion of the trick?

author: MK
author_rank: Regular Contributor
timestamp: January 08, 2016, 09:49:52 pm
content: Look up Tian on this page:https://sites.google.com/site/frankwiedmann/loopgain

author: xygor
author_rank: Regular Contributor
timestamp: January 08, 2016, 09:50:19 pm
content: Middlebrook, R.D., "Measurement of Loop Gain in Feedback Systems", Int. J. Electronics, vol 38, No. 4, pp. 485-512, 1975ltSpice has an example plus the explanation in examples/Educational/LoopGain and LoopGain2

author: dom0
author_rank: Super Contributor
timestamp: January 08, 2016, 09:59:41 pm
content: QuoteQuoteYou mean break the feedback loop "somewhere else"? Or I am not understanding you ...

author: TimFox
author_rank: Super Contributor
timestamp: January 08, 2016, 10:05:19 pm
content: See the references kindly supplied by MK and zygor above.Thanks to both of them.
Spice files and lack of Simetrix compatibility - Page 1
Forum section: electronics / projects

author: Circlotron
author_rank: Super Contributor
timestamp: June 04, 2017, 12:45:16 am
content: Been trying to run a simulation on Simetrix with a particular ST mosfet and the simulator throws all these errors saying this and that parameter in the mosfet spice file are not recognised. Edit out those lines in the file and then it gives other problems. What is a good free simulator someone can recommend? Running Linux and also XP in a virtual machine.

author: Circlotron
author_rank: Super Contributor
timestamp: June 04, 2017, 03:19:17 am
content: Installed LTSPICE in Wine and it imported the STW88N65M5 mosfet. Haven't gotten much past that because I just noticed that LTSPICE hasn't got any signal sources. At least they don't seem to be obvious.

author: Ian.M
author_rank: Super Contributor
timestamp: June 04, 2017, 04:44:10 am
content: For signal souces, place a voltage or current source, right click it then click the  button. There are also behavioural voltage and current sources (bv,bi) which implement an arbitrary maths function that may be defined in terms of simulation time, node voltages and component currents.

author: Circlotron
author_rank: Super Contributor
timestamp: June 04, 2017, 05:10:02 am
content: A voltage source is a *component*.Aha.

author: Ian.M
author_rank: Super Contributor
timestamp: June 04, 2017, 05:32:32 am
content: All probing stuff only appears after you've run a simulation (easiiest to start with a .tran analysis) and have a plot window open.You may need to look throughhttp://ltspice.linear.com/software/LTspiceGettingStartedGuide.pdf

author: Circlotron
author_rank: Super Contributor
timestamp: June 04, 2017, 05:44:16 am
content: And how on earth do you stop the windows going back to tiled horizontally every run?
SPICE Model: 74HC7014 - Page 1
Forum section: electronics / projects

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 24, 2016, 06:49:48 pm
content: If you were looking for a model of this obscure and very useful buffer chip, I've created one:Availability: this wasn't under contract, so I'm free to sell it as I see fit. PM me if you need a copy.I'll also put up a page on my website, sooner or later.FYI about models: I'll probably release them for free, eventually.Tim
Spice model for NE565 - Page 1
Forum section: electronics / projects

author: sevenofnine33
author_rank: Contributor
timestamp: January 25, 2018, 07:19:34 pm
content: Does anyone have a spice netlist for NE565?I cannot find it anywhere online.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 25, 2018, 07:32:09 pm
content: Doesn't appear to exist in vetted plaintext format.Here's something you can try:http://ace.ucv.ro/sintes12/SINTES12_2005/ELECTRONICS/E9.PDFClearly they spent zero time measuring pin characteristics (parasitic and ESD diodes, capacitance, voltage and current ranges), so use this as the most basic of examples -- if it works at all.Tim

author: sevenofnine33
author_rank: Contributor
timestamp: January 25, 2018, 07:44:20 pm
content: It has a lot of errors which I don't know how to fix, but thank you anyways.

author: Benta
author_rank: Super Contributor
timestamp: January 25, 2018, 08:25:25 pm
content: Hoping to find models for an IC that's obsolete since 20 years is somewhat optimistic...

author: sevenofnine33
author_rank: Contributor
timestamp: January 25, 2018, 08:57:42 pm
content: Quote from: Benta on January 25, 2018, 08:25:25 pmWell, I agree. Only specifications which can be found are from 1988, but tell that to my college teacher who gave me the project.

author: Benta
author_rank: Super Contributor
timestamp: January 25, 2018, 09:13:49 pm
content: Quote from: sevenofnine33 on January 25, 2018, 08:57:42 pmPerhaps your teacher expects more from you than just plugging a model into Spice? Your own analysis maybe? Just a thought.

author: Zero999
author_rank: Super Contributor
timestamp: January 26, 2018, 01:33:47 pm
content: Tell your college teacher you should be using a newer IC, such as the 74HC4046.
Spice to Simulink? - Page 1
Forum section: electronics / projects

author: Agrum
author_rank: Contributor
timestamp: May 29, 2020, 04:18:39 pm
content: Hello,I hope that I'm in the right section.I would like to know if there is a simple way to transform a LTspice model into Simulink.I'm very new to Simulink.Thanks

author: Mj12
author_rank: Contributor
timestamp: May 29, 2020, 08:56:13 pm
content: There seems to be way to convert SPICE to simulinkhttps://se.mathworks.com/help/physmod/sps/ug/converting-a-spice-netlist-to-simscape-blocks.htmlBut if you are talking ltspice macromodels (IC:s and stuff) you are likely out of luckI would recommend to look into component datasheet and device block diagram and recreate relevant parts in simulink. Not "simple" but not exceedingly hard either

author: jbb
author_rank: Super Contributor
timestamp: May 30, 2020, 01:32:09 am
content: It depends a lot on what you're trying to do. For power SimPowerSystems orPLECSare quite good.For signal analysis, I'm not really sure. The 'typical' Simulink approach would be to model the parts (likely in reduced detail) with Simulink blocks.

author: ahbushnell
author_rank: Frequent Contributor
timestamp: May 30, 2020, 11:58:44 pm
content: Quote from: jbb on May 30, 2020, 01:32:09 amI use PLECS all the time. They have models for power electronic components. You can even include C programing in blocks. Also does thermal and magnetic simulation as components.Andy
Spinning bicycle light. 100$ saved - Page 1
Forum section: electronics / projects

author: Miroslavus
author_rank: Newbie
timestamp: December 08, 2015, 10:52:04 pm
content: I found this lights for bike called Revolights and i tought i'd buy it but they sell them 99$(just front light). That is ridicolous price so i built it for 2$ instead. I ordered 100 SMD LEDs from china and with help of superglue, PCB and papeclips I built it. Works flawlessly. Check the video to see results for yourself.

author: sarepairman2
author_rank: Frequent Contributor
timestamp: December 09, 2015, 12:26:47 am
content: how will that stand up to the rigors of being on a bicycle wheel?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 09, 2015, 02:09:10 am
content: He can try 49 more times...

author: SaabFAN
author_rank: Frequent Contributor
timestamp: December 09, 2015, 07:14:15 pm
content: Quote from: sarepairman2 on December 09, 2015, 12:26:47 amI guess it will succumb to corrosion rather quickly if not regularly submerged in oil. Especially during winter when they put salt on the streets.Some rubber mounted on the outside, preventing the mechanism to be directly exposed to any splash of water and rain should be enough to prevent the oil from being washed away.
SPI/Power Isolation - Page 1
Forum section: electronics / projects

author: Lance
author_rank: Frequent Contributor
timestamp: August 06, 2012, 10:27:39 pm
content: I'm working on a power monitoring system, and I'm trying to figure out how to go about isolating everything.The current setup is to have multiple slave devices on modular boards (in case they get cooked) that communicate over SPI, that I want to isolate from the master.For handling the SPI lines, I came across these digital isolators by Analog Devices:http://www.analog.com/en/interface/digital-isolators/adum7440/products/product.htmlNot necessarily that exact device.What I'm trying to shop for now is isolation transformers to power the slave boards. Does anyone have any ideas on what's good to shop for?

author: PChi
author_rank: Frequent Contributor
timestamp: August 07, 2012, 02:31:48 pm
content: There are number of DC / DC Converters with isolation available. I haven't any recent experience of any particular models or manufacturers though. An idea of the input and output voltages with output current requirements along with isolation specifications would help.

author: digsys
author_rank: Unknown
timestamp: August 07, 2012, 03:04:44 pm
content: My common part I use for this sort of thing is -www.murata-ps.com/data/power/ncl/kdc_nme.pdfThere are several manufacturers that make a similar module.For the data I use -www.silabs.com/SupportDocuments/TechnicalDocs/si844x.pdfAwesome devices - low power (over entire data rate), high speed, high isolation. Similar to your find.Both beat optos hands down.

author: gxti
author_rank: Frequent Contributor
timestamp: August 08, 2012, 12:58:03 am
content: Dave did a video on this last week:There's a whole category for them on Digi-Key if you need inspiration:http://www.digikey.com/product-search/en/power-supplies-board-mount/dc-dc-converters/4325599For data I've also used the SI84 devices in the past, no complaints.

author: Lance
author_rank: Frequent Contributor
timestamp: August 08, 2012, 03:18:06 pm
content: This looks like a pretty good way to go.I really just need to power the slave micros that are doing the actual monitoring, so those are 5V or 3.3V (haven't settled on the model yet). In terms of the stuff I'm monitoring, the highest level is 28V as far as I know.The big reason I want isolation is because this is connecting via RS232 to a rather expensive PC104 stack.