hybridfree/eevblog-posts huggingface dataset:
SIM7600 HAT (WaveShare), 4G Modem - Page 1
Forum section: electronics / projects

author: babak7293
author_rank: Newbie
timestamp: September 21, 2023, 10:03:30 am
content: I am trying to achieve the sleep mode where current consumption will only be few miliamps but it would still be able to receive text messages.I am using the TX,RX and the DTR pin to put it in sleep mode and wake it up.According to docs, I send AT+CSCLK=1, and also pull up DTR, the NET LED goes off so i believe is in sleep mode. However the current is about 25 mA still. It should be few mA.Has anyone managed to put SIM7600 HAT into sleep mode? is a hardware change required (de-soldering something)

author: Emo
author_rank: Regular Contributor
timestamp: September 21, 2023, 11:27:50 am
content: Hi Babak7293,Sitcom does have a manual listed on its site specific for this situation; SIM7X00 Series_Sleep Mode_ Application NoteYou might have it already, otherwise you could request a copyEric

author: Kalvin
author_rank: Super Contributor
timestamp: September 21, 2023, 11:51:46 am
content: Are you using GPS? Have you also disabled GPS while in sleep state?

author: babak7293
author_rank: Newbie
timestamp: September 22, 2023, 09:00:18 am
content: thanks, I have turned off the GPS using AT+CGPS=0. I have already looked at that sleep application document, but still not able to get the current consumption down to few mA.

author: Kalvin
author_rank: Super Contributor
timestamp: September 22, 2023, 11:25:34 am
content: It looks like there have been similar issues with Lilygo's module. Lilygo's module is not identical to your module, but quite similar."Power consumption of SIM7600 in sleep mode #13"https://github.com/Xinyuan-LilyGO/T-SIM7600X/issues/13Please read thewholethread carefully before taking actions, though.Hope that helps.
SIM7600G-H - Page 1
Forum section: electronics / projects

author: Spark-Doctor
author_rank: Contributor
timestamp: December 12, 2023, 10:31:31 pm
content: Hi allI am working on a project and i have chosen the SIM7600G-H 4G module. I have one set up on a test rig and i can run all commands that i need except for one. I need to see the signal strength of all of the masts the module can see as a 1 shot deal and return the signal strength of each mast. I can run the test for the sim i have installed ok. I can work out the mast identifier no problem but for the love of god, i cant find an AT command to run this command.I am using PuTTY to run the commands.For the sake of my sanity, please help

author: tszaboo
author_rank: Super Contributor
timestamp: December 12, 2023, 11:18:19 pm
content: AT+CSQ is for signal quality. I don't think what you are looking for exists though.

author: ArdWar
author_rank: Frequent Contributor
timestamp: December 13, 2023, 06:22:02 am
content: If you know how to access the underlying SIM itself then maybeAT+CSIM? I never used that so idk if it actually works

author: liaifat85
author_rank: Regular Contributor
timestamp: December 13, 2023, 12:29:00 pm
content: Hi, what is the power supply that you're using?

author: Spark-Doctor
author_rank: Contributor
timestamp: December 13, 2023, 05:45:53 pm
content: Quote from: liaifat85 on December 13, 2023, 12:29:00 pm2 X 81650's

author: Spark-Doctor
author_rank: Contributor
timestamp: December 13, 2023, 06:34:13 pm
content: Quote from: ArdWar on December 13, 2023, 06:22:02 amThat command only returns the cell mast of the sim you have inserted. I can run AT+COPS=? and i getAT+COPS=?+COPS:(2,"vodafone UK","voda UK","23415",7),(1,"vodafone UK","voda UK","23415",2),(1,"vodafone UK","voda UK","23415",0),(3,"O2 - UK","O2 - UK","23410",2),(3,"O2 - UK","O2 - UK","23410",0),(3,"3 UK","3 UK","23420",7),(3,"EE","EE","23430",7),But it is not showing the signal strength.

author: liaifat85
author_rank: Regular Contributor
timestamp: December 14, 2023, 12:09:11 pm
content: Is the Module functioning well otherwise? Registering to the network?

author: Spark-Doctor
author_rank: Contributor
timestamp: December 14, 2023, 03:13:23 pm
content: Quote from: liaifat85 on December 14, 2023, 12:09:11 pmAbsolutly fine, i can run pretty much all commands.

author: Spark-Doctor
author_rank: Contributor
timestamp: December 14, 2023, 07:42:56 pm
content: Quote from: ArdWar on December 13, 2023, 06:22:02 amCSL make a devise that does it using a Telit Module but i don't know if it is a custom command or a Script that has been written for them.
SIM800 GSM module does not detect SIM card - Page 1
Forum section: electronics / projects

author: Yansi
author_rank: Super Contributor
timestamp: December 28, 2018, 05:08:08 pm
content: Hello,my friend recently showed up with a question, whether I could figure out why is his SIM800 module not connecting to the network.I have never worked with GSM modules, but being a rather quick-learner... I soon obtained the reason: SIM800 does not detect SIM card.Asking the module AT+CPIN? returns error of "SIM not inserted". (using the extended error message set, AT+CMEE=2)I have investigated, what the VCC, RST and CLK pins on the SIM card look like.VDD seems correct, module gives the card four times a voltage pulse of 1.8, 3, 3 and finaly 1.8V again, for a duration of few tens of ms. Which seems okay.Then I've probed the CLK pin - but wait, there is nothing I could recognize as a CLK signal, please see attached pictures.The RST pin of the SIM card does not produce anything reasonable either - all reset pulses are only 0.8V high. Whatta?So Okay, I know why it is not connecting to the network, but it does not really explain why the voltage levels are as observed.Is the module really messed up (ready for some widlarizing action) or is this behavior normal?Thank you,Y.//first two pictures is the CLK signal (measured on different power-ups), third one is the RST pin.

author: Yansi
author_rank: Super Contributor
timestamp: December 28, 2018, 08:37:26 pm
content: Meh! I have finally found the problem: A damaged ESD diode array near the SIM slot. Either that, or wrong type of component, its orientation or such may have been wrong.So, for others that may stumble upon this thread: Whenever you have problems with detecting the SIM card, check for damage of the ESD array for the SIM card slot!In my case only the diodes were dud, SIM800 module okay.
SIM800DS TCP question - Page 1
Forum section: electronics / projects

author: chamod
author_rank: Contributor
timestamp: January 13, 2016, 05:17:34 pm
content: I've been working on a weather station project, and I used a SIM 900 module to upload the data to a web server.Recently I started using a SIM800-DS for the same purpose. There wasn't much documentation on the module, but I managed to get a hardware design reference and an AT command reference after contacting the manufacturer. According to the documents the module mush have the SIMCOM http stack but it didn't respond to any of the http related AT commands.I realised I was stuck with a crippled firmware so I had to rewrite the code without using the simcom HTTP stack. Here I ran into a problem with get request.After configuring the module and connecting to the internet, I opened a TCP connection usingCode:AT+CIPSTART="TCP","requestb.in","80"And then, after sendingCode:AT+CIPSENDI formed a simple GET requestCode:GET /s64y13s6 HTTP/1.1HOST: requestb.infollowed by a 0x1a to indicate end of data. (I used requestb.in to test the requests).The module responds with a SEND OK. But doesn't display the server response. ("ok"). After a while, I get this request time-out message.Code:HTTP/1.1 408 Request TimeoutConnection: closeServer: CowboyDate: Tue, 05 Jan 2016 20:05:07 GMTContent-Length: 0It's unclear to me why this happens. (All the servers i tried either didn't respond or responded with a time-out. Should I do something more to indicate I've completed the request?Here's a link to my stackoverflow question. (unanswered)http://electronics.stackexchange.com/questions/209672/sim800-http-get-request-time-out
Sim800L Network connection problems - Page 1
Forum section: electronics / projects

author: picandmix
author_rank: Frequent Contributor
timestamp: September 22, 2017, 08:08:18 pm
content: Hi,Have used a Sim900 shield and a Sim800L coreboard basic module, both work fine using the same 02 UK network Sim card, both boards were purchased about 18 months ago.I ordered another Sim800L module to other day, and using the same circuit as above with a good 4.0v 3amp linear psu, it would not even connect to the 02 network, just flashing the net light quickly for 14 times, pausing for 3 seconds , then repeating.The CBAND and COPS AT data showed the same info on both the old and new 800L boards.Finally got the new Sim800L working when I fitted a SIM card using a different network, EE UK.Have looked on SimCom site for any update info etc but non found.Any suggestion as to what parameter/s may be different so I can get it to work with the my original 02 network sim card ?

author: Benta
author_rank: Super Contributor
timestamp: September 22, 2017, 09:12:49 pm
content: Are you certain that O2still supports G2? Several network operators don't anymore.

author: picandmix
author_rank: Frequent Contributor
timestamp: September 22, 2017, 10:55:35 pm
content: Quote from: Benta on September 22, 2017, 09:12:49 pmHi,Yes, its still works fine when I put the O2 sim card back in the old 800L and 900 boards, thats the puzzle ?Think the uk phone networks are hanging on to 2G a lot longer than many other countries.
SIM900 Breakout Board - Page 1
Forum section: electronics / projects

author: jechavarria
author_rank: Newbie
timestamp: October 03, 2013, 09:56:29 am
content: Hi! I want to share with you my last design. It's a breakout board for the SIM900 GSM module. Fits in a 50x50 mm board, and has an IO connector with many of the signals you need to control it. Also, as the board is designed to work with a battery, it also includes all the necessary components to charge and manage it. The internal power supply is 3.0V, so external controller must be work at this voltage. Here's the complete board info:http://www.jechavarria.com/2013/09/30/sim900-breakout-board/

author: jechavarria
author_rank: Newbie
timestamp: October 04, 2013, 09:38:19 am
content: Thanks! Also works well, I'll post an application with this board in the next weeks
SIMCOM 900 future compaibility in Australia? - Page 1
Forum section: electronics / projects

author: SL4P
author_rank: Super Contributor
timestamp: March 07, 2016, 12:47:55 am
content: Many embedded SMS modems available online - use the Chinese SIMCOM 900 chipset, and rightly claim to be quad-band...But only two of those four bands are in the Australian 3G allocation. (Others are PCS/DCS)Many claim the SIM900 is a 2G modem, but will this in fact have any effect on network registration and SMS handling after December 2016 ?(Hi Mat!)
Simcom module selection - Page 1
Forum section: electronics / projects

author: Martin Opresnik
author_rank: Newbie
timestamp: September 25, 2024, 08:43:51 am
content: 2G network might be shut down in future and I want to migrate from SIM868 (2G) to some module with LTE-M.I tried using SIM7080G, because it has same footprint and networking alone works great. But it has one limitation. GPS and TCP connection can't operate at the same time (looks I'm not alone with this problem).https://stackoverflow.com/questions/61857667/sim7080g-module-cant-send-data-over-tcp-while-using-gnssI want to record location every 15s, and keep TCP connection open. Just turning on GPS to get location and turning it off after receiving location will be too slow. In stackoverflow post there was mention of SIM7000G, but it looks like it's obsolete (https://www.digikey.com/en/products/detail/simcom-wireless-solutions-limited/SIM7000G/15841469), or is it?Is there similar module with GPS and LTE-M that can be used at same time?I would prefer both features in one module over separate modules to keep cost low.
SIMETRIX sweeping through multiple parameters simultaneously.  - Page 1
Forum section: electronics / projects

author: Glenn0010
author_rank: Regular Contributor
timestamp: October 04, 2019, 08:30:59 am
content: Hi All,I would like to sweep both through the current and gate resistor in my circuit simultaneously. Ideally I could also set the temp to 125 for example.I have managed to get it to sweep through one at a time but not more than one simultaneously. I can't seem to find documentation online to do this.Can anyone help?this is what I am doing to sweep through one parameter.Code:.simulator SIMETRIX.TRAN 20u SWEEP SINGLE PARAM=Current LIST 100m 200m 500m 1 2 3 5 10 15 20 25 30.simulator DEFAULTI have tried different syntax to try to get it to run but can't figure it out.
Simple way to highlight or colour code log custom text files - Page 1
Forum section: electronics / projects

author: ricko_uk
author_rank: Super Contributor
timestamp: September 02, 2024, 05:35:07 pm
content: Hi,I am generating text-type log files and would like to make them easier to read. Is there some utility that colors the entire line based perhaps on the first word/token?Thank you

author: IanB
author_rank: Super Contributor
timestamp: September 02, 2024, 05:49:29 pm
content: Perhaps useMarkdown?

author: xvr
author_rank: Frequent Contributor
timestamp: September 02, 2024, 06:04:13 pm
content: QuoteWrite log in HTML format, so any WEB browser could be used to open it.

author: PlainName
author_rank: Super Contributor
timestamp: September 02, 2024, 06:08:59 pm
content: LogFusion might do it. Well, I know it can do whole line highlighting based on some text in the line, but I'm not sure you can restrict that to the first word.https://www.logfusion.ca/Worth stating if you want something that will deal existing format, of if you're up to changing the format to suit the viewer (perhaps by embedding HTML or Markdown as suggested above).There is a very good log file viewer that would easily do this (and more) but I loath the developer's greed and restrictive license, so I won't mention it

author: ajb
author_rank: Super Contributor
timestamp: September 03, 2024, 04:03:14 pm
content: I don't know of anything ready-made, but it would be pretty easy to turn a plain text file into HTML using JavaScript, with whatever content-based styling you want. You can do everything in a single client-side js/html file, so it would be very portable. It would also be very easy to add interactive filtering, navigation ('jump to next error' links), statistics, etc.Quote from: IanB on September 02, 2024, 05:49:29 pmI love me some markdown, but I don't know of an implementation that includes any kind of color coding. You could of course apply a custom stylesheet that assigns colors to different emphasis tags, but then you wouldn't be able to use them for emphasis as well, if that were desirable.

author: unseenninja
author_rank: Regular Contributor
timestamp: September 03, 2024, 08:01:08 pm
content: A program called "baretail" can do what you need.Still free fromhttps://baremetalsoft.com/baretail/I've used it for years on Windows systems as it can follow a log as it is being written, as well as viewing them after the fact.

author: ricko_uk
author_rank: Super Contributor
timestamp: September 03, 2024, 08:24:43 pm
content: Thank you all!I was literally typing a reply when @unseenninja posted his reply. What he suggests and also LogFusion do exactly what I was looking for. But using HTML is also a nice suggestion. So for the future I will also implement HTML formatting into my log file genertor.Thank you
Simple (cheap) power line communication circuit - Page 1
Forum section: electronics / projects

author: xtv
author_rank: Contributor
timestamp: August 03, 2015, 11:11:00 pm
content: Hello,I'm no electronic engineering, but I'm willing to build a simple (and cheap) circuit for sending data over the power line in my house (220v ac).As it's possible having data modulated in different frequencies travelling over the same wire pair, like in coaxial cables (obviously, I'm aware they're designed for carrying a wide range of frequencies, and just for that), I'm wondering what would take to do a very simple circuit for power line communication.For that I have some doubts, which I will list below. I'm not lazy, so if you can't give a straight answer, but point a direction on where to head for getting these data, I will dig for them. Some of them are:1. Is it possible for doing it (the modulation and signal injecting) with simple transistor(s)?2. How am I suppose to "isolate" my transmitter from the high voltages running in the line?3. What are the output peak voltage I will need for the transmitter signal output?4. For the receiver, I'm wondering if I can use passive RC and/or LC filters for recovering the signal ?5. Any other useful considerations.This is all for the sake of curiosity, save the safety warnings. I wont burn my house down!Thank you all!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 04, 2015, 12:02:38 am
content: There have been, from time to time, these household intercom devices, which use low frequency AM radio waves carried on the power lines. Such a circuit could be built in just a few transistors if you're desperate (such as a keyed oscillator and regenerative receiver), a good one in perhaps 10 transistors (if you're keen).Representative circuits should be available online.Isolation is easily obtained with an isolation transformer, or using Y1 type (line to earth) capacitors.What kind of communication are you expecting? Morse code, voice, digital?Tim

author: Richard Crowley
author_rank: Super Contributor
timestamp: August 04, 2015, 12:22:59 am
content: There are schematic diagrams of various power-line communication circuits out there for the Googling.But the state of the technology for wireless transmission has gone way beyond what is practical to do over the power lines.There have been power-line communication schemes for over 50 years but it has never become very popular because it was never the best way of doing anything.As @T3sl4co1l said, is rather difficult to discuss this topic without a better idea of WHAT KIND of "communication" you are talking about.
Simple 30 channel current measuring approach? - Page 1
Forum section: electronics / projects

author: zzattack
author_rank: Regular Contributor
timestamp: June 12, 2021, 04:48:21 pm
content: I'm looking for some advice for the approach of a project that I want to do. My desire is to continuously sample currents going into about 30 LED panels simultaneously. A sample rate of 2Hz would suffice, and the measurements are to be transfered over UART to a Raspberry Pi.What I have in mind is to use a ACS712 for the current measuring of each channel, and some multi-channel analog to digital converters along with a STM32F0 for reading out the ADCs, either over SPI or I2C. The TI ADS1158 seems a reasonable choice for the ADC, but from the datasheet its SPI interface seems quite annoying to deal with. There's a bunch of 8-channel devices that also seem capable, but it's hard to judge whether any of them integrate nicely with some microcontroller code. Ideally, I wouldn't need too many of them (will prototyping about 10 by hand..), so a component that's available in a hand-soldering friendly package is prefered.Any suggestions, pitfalls or advice for things I should take into consideration are appreciated.

author: SiliconWizard
author_rank: Super Contributor
timestamp: June 12, 2021, 04:59:19 pm
content: If your sample rate is that low, then you'll have to seriously low-pass filter the current measurements themselves; in which case, "simultaneous" sampling is useless IMHO. You can just use one ADC and an additional analog multiplexer.Note that that's what the ADS1158 does - it just has an internal analog MUX. You'll need two of them. They are about $10 each (for low quantities.) I don't see what the problem is with its SPI interface.If the voltage span fits your requirements, you could consider using a 32-channel MUX instead, such as the ADG731, and then a single-input 16-bit ADC (if you really need 16-bit?) That's still two chips, but that'll be cheaper. Oh and if 12-bit is enough, you could consider using the internal ADC of some MCU, many do have 12-bit ADCs these days. The ADG731 itself is about $5. It's available in TQFP, which is easy to hand solder.

author: Terry Bites
author_rank: Super Contributor
timestamp: June 14, 2021, 02:30:59 pm
content: https://www.tindie.com/products/fercsa/32-channel-adc-wi2c-for-arduino-raspberry-pi/#specs
simple 48Vdc 50A buck converter for battery (lithium) charging? - Page 1
Forum section: electronics / projects

author: max_torque
author_rank: Super Contributor
timestamp: September 21, 2022, 11:50:56 am
content: Does anyone know of any off-the-shelf DC DC converters that are easy to integrate with a microcontroller to enable current controlled lithium battery charging?max system voltage is 50.4v and max current would be around 50A. I don't require any high precision or low ripply and the buck ratio is always going to be between 100 and approx 75% duty cycle (ie might get away with passive rectification?. Does not need to be isolating architecture either. Supply would be an off the shelf power supply module (240Vac to 48Vdc) and the converter would need to sit between the psu and the battery to control the charging current into the battery. As it's a lithium battery the votlage swing between 100 and 0% SoC is only roughly 25% of the max voltage.Alternatively, what about a controller IC that can easily work with some sort of digital or analgour current control signal?Anyone got any ideas/suggestions

author: H.O
author_rank: Frequent Contributor
timestamp: September 21, 2022, 07:41:52 pm
content: Vicor (not known for making cheap stuff) has anapp noteon using their DC/DC converters as current sources specifically for battery charging. I believe the specific series of converters they're "using" in the app note are obsolete but it might be worth looking into.

author: gf
author_rank: Super Contributor
timestamp: September 21, 2022, 10:27:34 pm
content: Solar MPPT charge controllers rated for 48V/50A should limit the charging power to 2.5 kW, or to the maximum power that can be drawn from the source, whatever is lower. And of course they are also supposed to stop charging when the battery is full. Input voltage should be more than 48V, though (IMO most of them are step-down).

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 22, 2022, 01:08:58 pm
content: Telecom rectifiers should have current limiting and voltage adjustment already, some of them programmable. What might be difficult is figuring out what signals do that if there are no trimpots on the unit itself for that adjustment.
simple 8bit serial data switch circuit? - Page 1
Forum section: electronics / projects

author: yalect
author_rank: Regular Contributor
timestamp: May 17, 2024, 06:01:06 am
content: Hi,I would like to ask you if I can build simple circuit that can manage with small 8bit serial data asynchronous using for examplePIC16F84as detector, without care about the rate of the data or clock, maybe there was already proved data or Idea?.Thank you.

author: jwet
author_rank: Frequent Contributor
timestamp: May 17, 2024, 03:32:45 pm
content: If I understand what you're asking- you could use a Shift Register like a 74HC595 to serialize data using an external clock. A microcontroller could receive this data.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: May 17, 2024, 10:16:12 pm
content: Quote from: yalect on May 17, 2024, 06:01:06 amasync data does not have a clock ? What do you really mean here ?If you mean async data (UART)without care about data rate or slave MCU clock speed, you need some form of Autobaud.Systems like LIN bus send a 0x55 character as autobaud.Or, you could look at the SENT bus (Single Edge Nibble Transfer) - that sends a calibrate pulse of 5T and then encodes a nibble into the next edge delay of 12-27Thttps://www.tek.com/en/solutions/industry/automotive-test-solutions/in-vehicle-networks/sent-sensor-bus-troubleshootingThe SENT bus is designed for modest baud rates and has fewer edges for lower RFI.Note that modern, low cost MCUs have better oscillators than the old PIC16F84, and many are able to manage UART coms without needing self-calibrate steps.
Simple amp I can build in a day - Page 1
Forum section: electronics / projects

author: skyler
author_rank: Regular Contributor
timestamp: November 22, 2014, 04:44:02 am
content: I need to amplify microphone level audio (not electret, just AC) to small portable speaker audio levels for a portion of a birthday present I need to create in a day.The audio will come from an induction pickup coil, and I want it to pick up the slightest signals, like the hum from an AC line in a house.Is there a simple circuit from parts from RadioShack that I can build? I would like it to be DIY, and not just buy the amplified speaker they have.Thanks
Simple Asynchronous serial data display circuit - Page 1
Forum section: electronics / projects

author: yalect
author_rank: Regular Contributor
timestamp: June 16, 2024, 10:31:56 am
content: Hi,May someone help I want to design or draw circuit of simple data reciever or decoder Asynchronous 8bits maybe with latch D, the important that it can desplay 8bits (8 LEDs)?.Thank you.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: June 16, 2024, 07:21:33 pm
content: See the similar threadhttps://www.eevblog.com/forum/projects/clockless-serial-to-parallel-interface-options/msg5542351/#msg5542351Has some part numbers and drawings.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: June 16, 2024, 10:42:40 pm
content: Quote from: yalect on June 16, 2024, 10:31:56 amIf you want UART to LEDs then the TM1652 mentioned in another thread on here, could be usable.That's very cheap (~ 6c /150+ at lcsc ) in SO16N, can drive 5 x 8 matrix.

author: yalect
author_rank: Regular Contributor
timestamp: June 17, 2024, 08:45:24 am
content: Thank you.But because I didn't talk about serial to parallel converter and RS-232 and as I said maybe just with Latch D and certain CLK can configer some data if we haven't PC there or programmed machine?

author: Ian.M
author_rank: Super Contributor
timestamp: June 17, 2024, 10:35:45 am
content: It depends what type of serial data the device you want to monitor can output. Different solutions are needed for seperately clocked serial data, (e.g. like SPI with or without a separate select or reset line to indicate the start of the data frame), I2C, Dallas 1Wire, async UART (i.e. logic level with RS232 character framing) or more exotic self-clocking protocols that may use Manchester encoding or one of many variable bit rate encodings.If you have full programmable control of the device sending the data, you've got a lot of options. One very low cost but rather hacky one that hasn't been mentioned recently is Roman Black's Shift1 protocol. It drives a chain of one or more 74HC595 8 bit SIPO shift registers from a single MCU I/O pin.See:https://www.romanblack.com/shift1.htmand this topic here:https://www.eevblog.com/forum/projects/latched-shift-register-74hc595-control-via-single-mcu-io-pin/

author: PCB.Wiz
author_rank: Super Contributor
timestamp: June 17, 2024, 07:39:47 pm
content: Quote from: yalect on June 17, 2024, 08:45:24 amYour title states asynchronous, but certainly many shift registers use Clk & Dat lines.If you are just driving LEDS, you can even fast shift in new data and avoid a separate latch line.That is no longer asynchronous, so you may need to edit your title.
Simple available GPS + cellular module - Page 1
Forum section: electronics / projects

author: Wor3d
author_rank: Contributor
timestamp: April 03, 2022, 03:30:29 pm
content: Hi all,I am developing a product where we have need for a GPS tracking via LTE (or possibly NB-IoT, if that would help).Preferably we would have just one module with AT commands / UART or similar.I am wondering if any of you have experience with modules like this, and can recommend some (or recommend which ones are trash) -> also with regards to availability, which is killing everyone these days...Thank you very much for your input!

author: Smokey
author_rank: Super Contributor
timestamp: March 01, 2023, 07:23:34 am
content: What have you guys used for embedded cellular?

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: March 01, 2023, 10:18:31 am
content: Buy a low cost android mobile phone. Rip apart the screen and the casing and the battery. What you have left with is a GPS tracker with LTE. You can write your own linux program on it.

author: jc101
author_rank: Frequent Contributor
timestamp: March 01, 2023, 04:40:54 pm
content: Would the Wurth Adrastea-I be a suitable fithttps://www.we-online.com/en/components/products/ADRASTEA-I?Not that cheap but available.

author: Bicurico
author_rank: Super Contributor
timestamp: March 01, 2023, 07:20:55 pm
content: Get a separate NMEA GPS module and a SIM900 or similar module.

author: Smokey
author_rank: Super Contributor
timestamp: March 01, 2023, 11:04:14 pm
content: This is sort of interesting:https://dev.blues.io/hardware/notecard-datasheet/note-wbna-500/https://www.digikey.com/en/products/detail/blues-wireless/NOTE-WBNA-500/15193962For all that stuff $64.90 isn't totally unreasonable.
Simple Battery Management  - Page 1
Forum section: electronics / projects

author: jpanhalt
author_rank: Super Contributor
timestamp: January 25, 2024, 05:45:52 am
content: I have simply tended to ignore battery fuel gauges and charged when I thought it was needed. Now with lithium, adding fuel gauges (coulomb counters) seems popular. Examples are the TI BQ27xxx and MAX17320 fuel gauges.Are there simple solutions that combine a BMS charger with some rough indicator of state of remaining charge? For example, I have a recent project that uses a 2000 mAh prismatic cell, MCU, and GLCD. With the screen backlight off it seems to run "forever". With the backlight on, it still gets well over 10 hours of continuous use. It would be helpful to know when it was down to about 1/4 full charge. I don't need a closer percentage or calculation of time remaining.

author: Miyuki
author_rank: Frequent Contributor
timestamp: January 25, 2024, 06:17:20 am
content: Just measure a voltage and put it on the discharge curveFor Li-ion works just fineFor better accuracy can have two curves, one with and the other without backlight

author: Siwastaja
author_rank: Super Contributor
timestamp: January 25, 2024, 09:38:06 am
content: Simplest is, measure voltage with MCU using voltage divider, come up with typical discharge curve for your cell, and estimate based on voltage. You can average over a few minutes.This fails with very large discharge current peaks, especially in cold, when the terminal voltage is far from open-circuit voltage due to voltage sag. OTOH, it fails in an intuitive way; battery indicator temporarily showing lower number when user does some "heavy duty" operation, then recovering back does not cause complaints, even laymen understand batteries work like this. It also gives a hint that the battery is sagging close to the cutoff limit under high load. With a coulomb counter, this is hidden from the user, and you need to come up with some other way to communicate "you can still use the device but with reduced power".The usual consumer li-ion chemistries are far from being flat. You can get pretty accurate SoC indication, say +/- 5%, from voltage alone, ignoring those large peaks which divert outside of this error range.
Simple battery meter in raspi project - Page 1
Forum section: electronics / projects

author: PhelarNord
author_rank: Newbie
timestamp: December 19, 2019, 08:34:24 pm
content: Hi!I´m in need of a simple battery meter for device that needs to tell its battery status over a ip network.The device loads a raspi so i´ll use this one for the input...and on to the network. I dont want to use the i2c or the spi intefaces soim now left with the gpio´s.So, what i came up with was the LM339 and four of the raspi's gpio´s. I´ll get four voltage thresholds to display battery health.Now i wonder if there is even a easier way to do this with even less of the gpios or another smart way to use them that i missed, anotheric maybe?Cheers

author: viperidae
author_rank: Frequent Contributor
timestamp: December 20, 2019, 04:41:54 am
content: A ds2450, 1 gpio and the w1-gpio kernel driver

author: PhelarNord
author_rank: Newbie
timestamp: December 20, 2019, 06:36:17 am
content: The DS2450 is a great idea, but it´s obsolete, right?
Simple but Fully Discrete Triangle Wave Generator - Page 1
Forum section: electronics / projects

author: PinePolarBear
author_rank: Newbie
timestamp: May 03, 2019, 06:08:20 pm
content: Hello. I'm working on a fully discrete class D amplifier. I'm looking for a triangle wave generator design. It would be preferably simple, but it needs to go above 250 kHz. Thanks.

author: JPortici
author_rank: Super Contributor
timestamp: May 03, 2019, 06:35:26 pm
content: Component selection and how to get around all the gotchas to achieve an triangle that as pure and symmetric as possible is left as an excercise to the reader

author: Benta
author_rank: Super Contributor
timestamp: May 03, 2019, 06:57:08 pm
content: You should add that the triangular output is from the first amp.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 03, 2019, 07:51:09 pm
content: I've used some variant of this, many times:https://www.seventransistorlabs.com/Images/Flashlight2_Schematic.pngIC2 is a astable multivibrator and PWM comparator. Q4A isn't necessary, but it improves linearity. If not needed, it can be replaced with a pull-up resistor.Note that you don't want to skip the rest of the circuit: IC3B compares the inductor current to the current setpoint, providing a first line of defense against destruction of transistors or other components. The output current simply cannot be anything other than what it can be set to, within a controlled range. IC3A then controls that current, in order to regulate the output value (in this case, a combination of output current and voltage for driving LEDs, but just voltage would be fine for a power supply or amplifier).The chained error amplifier topology also avoids putting the double-pole output filter inside a single loop. Instead, the inductor is in the first loop, and the capacitor and load in the second. This is much easier to compensate, and gives much nicer waveforms.Tim

author: David Hess
author_rank: Super Contributor
timestamp: May 04, 2019, 10:03:52 pm
content: Oscilloscope sweep generators meet your requirements so you might want to study how they work.I would also consider bipolar implementation of a PUT based relaxation oscillator with the resistance replaced with a constant current source.https://www.instructables.com/id/Circuit-Collection-of-the-Programmable-Unijunction/
Simple but powerful SAMD11 PCB - Page 1
Forum section: electronics / projects

author: Lt_Flash
author_rank: Regular Contributor
timestamp: September 06, 2019, 11:54:45 am
content: Hi,This is my project of basic SAMD11C14 MCU breakout. It supports all required SWD pins, I2C, SPI and others and is very simple and straightforward to reproduce. SAMD11 is quite a powerful MCU and it comes in a great SOIC package that's very easy to solder. Please have a look at my project here and feel free to ask any questions!https://workspace.circuitmaker.com/Projects/Details/LtFlash/SAMD11-Base-BoardP.S. Please read my comments on this project as you may want to add 1kOhm resistor on SWCK line and some PTC fuse if you're going to drain much current. Also remember, that MCU pins can provide only small amounts of current and you may need to use MOSFETs even to feed LEDs. Thanks!
Simple circuit to keep a panel LED on for fast signal visualization - Page 1
Forum section: electronics / projects

author: John Anderson
author_rank: Contributor
timestamp: August 11, 2018, 03:27:08 pm
content: Hi,I was trying to came up with the simpliest analog, low-part count circuit to keep a panel LED on for enough time to be able to visualise a fast control signal. What I look for is to fire the LED with a digital signal (5V) of, let's say, 1 us pulse, and keep it on for about 1 second, enough for the human eye to catch the information.My original idea was an RC delay schema and firing the LED with an SCR, but the part count is rising pretty quickly as soon as I have to cut off the SCR current flow.Any good idea is very much appreciated. Thank you!

author: Audioguru
author_rank: Super Contributor
timestamp: August 11, 2018, 03:42:32 pm
content: A monostable made from a 555 timer will do it.

author: Benta
author_rank: Super Contributor
timestamp: August 11, 2018, 04:06:20 pm
content: CD4538.

author: John Anderson
author_rank: Contributor
timestamp: August 11, 2018, 05:13:59 pm
content: OK, this is exactly the functionality requested, but I forgot to mention that PCB-room is limited, so for this reason I was thinking in a discrete component solution like an SCR. Any other ideas?Thank you again.

author: Benta
author_rank: Super Contributor
timestamp: August 11, 2018, 05:22:34 pm
content: For a 1-second delay using discrete parts, your timing cap is going to be so large that all other solutions (4538, 555) are smaller.

author: james_s
author_rank: Super Contributor
timestamp: August 11, 2018, 10:32:53 pm
content: A microcontroller could do this easily. There are a number of very small microcontrollers out there in with only a few pins.

author: David Hess
author_rank: Super Contributor
timestamp: August 12, 2018, 09:16:11 pm
content: I usually use a pair of gates to make a monstable multivibrator but a single gate can be used as a pulse stretcher in some applications.

author: iXod
author_rank: Frequent Contributor
timestamp: August 13, 2018, 04:58:47 pm
content: Quote from: james_s on August 11, 2018, 10:32:53 pmSome examples, please?Thanks.

author: Bratster
author_rank: Frequent Contributor
timestamp: August 13, 2018, 05:42:03 pm
content: Quote from: iXod on August 13, 2018, 04:58:47 pmPic12f675Attiny85That's from a quick Google for 8 pin microcontroller...Sent from my Fi Moto x4 using Tapatalk

author: james_s
author_rank: Super Contributor
timestamp: August 13, 2018, 07:04:26 pm
content: 8 pin is huge, look at the ATTINY10-TSHR, SOT23-6 package, costs 34 cents each in single quantities. It's smaller and cheaper than a 555, and requires no external components.
Simple CMOS Analog  Square-Rooting and Squaring Circuits - Page 1
Forum section: electronics / projects

author: promach
author_rank: Frequent Contributor
timestamp: April 09, 2020, 08:06:09 am
content: ForSimple CMOS Analog Square-Rooting and Squaring Circuits, how to derive equations 13 and 16 ?

author: nuno
author_rank: Frequent Contributor
timestamp: April 09, 2020, 10:04:53 pm
content: There's something extra on your link...https ://sci-hub.tw/https://ieeexplore.ieee.org/document/129463?
simple cycle timer - Page 1
Forum section: electronics / projects

author: dosensuppe
author_rank: Contributor
timestamp: October 02, 2025, 08:14:46 am
content: Hello. Thought this thing would be simple enough, and ofc I tested everything on breadboard beforehand. It's just a counter which pulls the tranny low every period, hence activating the NE555 monoflop. But after etching my PCB I can't get the friggin NE555 monoflop to work. Everything else works fine.Please just tell me I made some stupid mistake wiring something up.

author: WattsThat
author_rank: Frequent Contributor
timestamp: October 02, 2025, 12:00:21 pm
content: High value 555 timing caps are not a good idea… C4 leakage? Monitor the voltage on C4, if it starts to ramp up and fails to reach… what is it, two thirds VCC?, the 555 will never change state and remain stalled since the comparator trip point is never reached. Maybe a tantalum rather than a cheesy electrolytic but even that’s no guarantee.Q2 base drive could be too low as well at 500ua if the 555 never releases and starts to ramp up voltage on C4.

author: Smile2016
author_rank: Regular Contributor
timestamp: October 02, 2025, 12:13:17 pm
content: Check Q2's footprint , then the potentiometers .... cheers ! Check D1 orientation...

author: synccond
author_rank: Contributor
timestamp: October 02, 2025, 12:32:17 pm
content: Move the 4060 to the output of the 555, allowing better operating frequency for the 555. You should be able to use a bare bones simple oscillator at lower freq to feed the 555, rather than crystals and divide-bys. What kind of accuracy is really needed, after all.

author: Zero999
author_rank: Super Contributor
timestamp: October 02, 2025, 12:38:50 pm
content: Are you sure about putting 24V on a USB connector? That could lead to smoke, if something which expects 5V is plugged in.Switching the ground can also cause problems. If the power supply to your circuit is earth ground and you use it to switch something who's 0V is also connected to earth ground, then it won't switch it off, because the current will find a path throuh earth ground, bypassing the switching transistor.Finally, have you considered using a small microcontroller? As well as being cheaper and simpler, the internal RC oscillator will be much more accurate and stable, than discrete components.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: October 02, 2025, 06:45:01 pm
content: Quote from: dosensuppe on October 02, 2025, 08:14:46 amIf it worked fine on the breadboard, look for shorts or opens on your etched pcb.Did you clean it thoroughly?Also check with a lower pull-up and timing cap, in case the pcb has poor cleaning leakage problems.
Simple DDS amp/buffer - Page 1
Forum section: electronics / projects

author: Wirehead
author_rank: Regular Contributor
timestamp: October 27, 2015, 02:21:27 pm
content: Hi All,I've been brewing on a simple DDS amp/buffer for those cheap ebay AD9850 modules. I'm only focusing on a sine wave at the moment, as that's what I'll mostly use in my audio stuff. (I can later add something with a 74hc14 and the same style amp/buffer).I just made up something quick with an NE5539 (wide bandwidth, high slew rate op amp) and a BUF634 buffer to drive loads that demand it. 50Ohm output impedance; 10Hz <-> 10Mhz.Anywho, it works pretty good (on breadboard, not ideal at high bandwidths for the NE5539) - so I'm looking to transfer this over to a small PCB. Planning to go SMD; but that NE5539 is _old_.So, anyone have a suggestion for a replacement? Looking for something that has an equal (or better) bandwidth range; but comes in SMD; better or equal slew rate (keeping those square waves in mind in the future..); same for the gain bandwidth.If I make a PCB, I'll open-source it. It would be nice if you can get samples of the parts in question. That way other people can build it pretty cheap as well..I've attached a schematic and some scope shots. Output is -pretty- linear. Hey; it doesn't have an AGC, but it's cheap and good enough

author: quantalume
author_rank: Unknown
timestamp: October 27, 2015, 03:49:24 pm
content: I'm using the ADA4857-1 in the SOIC-8 package for the same purpose. It seems to perform fine through 30 MHz at a gain of 4, which gives me just over 1 VRMS into 50 ohms. Analog Devices also have a universal evaluation PCB available for SOIC-8 high-speed op amps, the UG-101. It has SMA input, output and disable interfaces. It's a little pricey (USD 21), but it is a good study on proper RF PCB design.

author: Farley
author_rank: Regular Contributor
timestamp: October 27, 2015, 06:29:43 pm
content: You might take a look at the LMH6703 from TI.

author: Wirehead
author_rank: Regular Contributor
timestamp: October 27, 2015, 07:07:29 pm
content: Thanks for the suggestions - ADA4857 looks nice; but the LMH6703 looks like a very good match - even when adding a decent amount of gain. (Vout 4V-pp). Couple that with the fact that samples from TI reach me very fast and without any hassle. Winner
Simple Discrete Battery Charger with Status LEDs - Page 1
Forum section: electronics / projects

author: nathanpc
author_rank: Unknown
timestamp: October 25, 2015, 12:19:45 pm
content: Today I had the idea of creating a very simple discrete battery charger based onthis circuit bigclive showed in his videosince it already had that really cleaver "cell in" indicator trick, but I wanted to add a "charged indicator", so I just added another transistor to indicate just that and light a green LED:I've done some simulations and also breadboarded the circuit. It works quite well, but as you might have already guessed the LED starts to turn on before the battery is completely charged, but that's fine all you need to do is check if the LED is bright and not dimly lit.Another idea that I had was to add a another transistor to switch off the charger when the battery is full, but I still haven't tried it out yet:I just thought it was a nice little circuit to share if anyone is interested. Feel free to let me know if you liked it, suggest any improvements, or point out any mistakes I've made.

author: Paul Price
author_rank: Super Contributor
timestamp: October 25, 2015, 04:20:16 pm
content: You have presented a design with unknown battery voltage, charge requirements, resistor values, etc.I hope you aren't doing this because you have hopes to patent your cleaver design.You have left out the cleaver "battery-in" indicator.That being said, using a LM339 comparator instead of discrete transistors to detect voltage levels would make your end of charge point and charge operation LED indicators quite precise in operation, all with just a small increase in complexity.

author: nathanpc
author_rank: Unknown
timestamp: October 25, 2015, 04:40:00 pm
content: Paul, it's intended to be used with NiMH. I left out the battery voltage because you can tweak R3 and R4 to any battery voltage you want, also the "battery-in" indicator is part of the constant current regulator. I've done this just as a fun experiment to play around with transistors and learn more, I would never patent this or use it in any serious charging circuit, it was just a project to learn more and create a extremely simple charger entirely with discrete components.
Simple DIY car alarm - Page 1
Forum section: electronics / projects

author: zerocool
author_rank: Newbie
timestamp: August 31, 2013, 03:22:34 am
content: Hey guys, new to the forum but a long time watcher! My dad got a car (For me later! I'm 15) and he doesnt like the alarm that came with it, he wanted a simple one that has a wireless remote with a relay receiver hooked up with the dome light and the siren. That part has been taken care of with a 5$ wireless relay switch off amazon. But I dont want it to simply turn on and off a siren, Based off the relay I wanted it to also lock and unlock the doors and flash the turn signal lights. The thing is this is a single channel SPDT relay. The keyfob has a lock and unlock that go together. The wires are all there, but I cant wrap my head around a circuit for this. It has to pulse 1 relay for the lights and the door lock wires are as follows 1 LOCK 2 GROUND 3 UNLOCK , so a single relay wont work for everything. Any help with this is appreciated, mainly because when I start driving this car (1989 Mitsubishi Montero 4X4) will be mine!

author: zerocool
author_rank: Newbie
timestamp: August 31, 2013, 03:31:08 am
content: Oh and the lock and unlock have to be pulsed shortly along with the lights, the siren has to stay on until unlocked. And the wireless relay is a latching one but I can set it to be on when the button is pushed and off when not pushed too.

author: SeanB
author_rank: Super Contributor
timestamp: August 31, 2013, 05:24:53 am
content: 4 button Keeloq remote control and 2 receivers. 2 buttons are set up as momentary switches and operate the lock and unlock function using the one 2 channel receiver set up as a momentary output, and the third is set up as a latching output and you use the one button to operate the one channel. Most remote receivers have the ability to set the output as either a momentary or as a latching output, and using Keeloq gives you a rolling code which is a little more robust and not prone to false triggering.If you buy a top end receiver you can set each individual output as either pulse or latching, but will have to add external relays as they only give an open collector output as they are meant to interface with gate and door controllers. 2 simple 2 channel receivers are likely to be cheaper, and they have relay outputs.