hybridfree/eevblog-posts huggingface dataset:
Crystal SMD packaging... - Page 1
Forum section: electronics / projects

author: alank2
author_rank: Super Contributor
timestamp: June 15, 2014, 06:15:01 pm
content: Hi Everyone,Is there a benefit in terms of reliability between a can type crystal modified for SMD, or one that looks like other SMD parts?http://www.digikey.com/product-detail/en/ABLS-8.000MHZ-B4-T/535-10212-1-ND/2184247http://www.digikey.com/product-detail/en/NX8045GB-8.000000MHZ/644-1018-1-ND/1128890Thanks,Alan

author: marshallh
author_rank: Unknown
timestamp: June 15, 2014, 06:19:26 pm
content: Have used both with no difference detected in both reflow and hand soldereing

author: rob77
author_rank: Super Contributor
timestamp: June 15, 2014, 06:25:12 pm
content: they might have different stability ? according to my experience (talking about cheap xtals) : the smaller the package - the higher the ppm is. but i might be wrong

author: theatrus
author_rank: Frequent Contributor
timestamp: June 15, 2014, 06:36:02 pm
content: You can even get crystals in polymer packages as well, instead of the more usual metal can. The main advantage is cost.

author: alank2
author_rank: Super Contributor
timestamp: June 16, 2014, 01:10:08 pm
content: What do you guys think about longevity. The metal can they've been doing for decades, do you think it is tougher and has a longer mtbf vs the smd style ones?

author: SirNick
author_rank: Frequent Contributor
timestamp: June 17, 2014, 08:52:23 pm
content: I was wondering the same thing recently, since I started looking for SMD equivalents to all the PTH stuff I keep in personal inventory. Then I started noticing SMD crystalseverywhere. I guess I just didn't notice before because I didn't know what I was looking for.For e.g., I have a stack of Juniper hardware behind me... router chassisesses, interface cards, routing engine cards, you name it. There are a ton of SMD crystals on those.If it's good enough for production telco equipment, it's good enough for me, and probably for you. I say: Match the part specs to the requirements as usual and sail on.

author: dannyf
author_rank: Super Contributor
timestamp: June 17, 2014, 09:11:17 pm
content: QuoteI have used both and I don't think there is much difference. The metal can allows you to ground it to minimize emi.
Crystal value labelling - Page 1
Forum section: electronics / projects

author: LukeW
author_rank: Frequent Contributor
timestamp: February 09, 2016, 09:30:50 am
content: I have a batch of crystals here.They are through-hole, HC-49US crystals made by TXC.I'm 95% sure a batch of 4.096MHz crystals is what I ordered, but they're not labelled as 4.096MHz.They are labelled as follows:TXCG4.00Np2NIs there any weird product marking system going on here to encode the value? Are they 4.096MHz as expected, or 4.00MHz?

author: amyk
author_rank: Super Contributor
timestamp: February 09, 2016, 10:32:01 am
content: I think those are 4000000Hz, best make an oscillator and check. 4.096MHz (which is 4096000Hz, not 4194304Hz...) will be labeled 4.096.
Voltage level issue with CS5532/34 ADC - Page 1
Forum section: electronics / projects

author: Tomkki
author_rank: Newbie
timestamp: July 03, 2020, 06:14:53 am
content: Hello,I just implemented python based driver for the the Cirrus Logic CS5531/32/33/34 ADC (https://www.cirrus.com/products/cs5531-32-33-34/). I followed the application note and hooked up a +-3V as VREF. The digital site is driven from 3V3 of the raspberry pi.So far so good. My 20Hz sign wave looks pretty and I am able to sample with full speed (3200 SPS)Now, when I start to make "many conversions" the amplitude of the signal collapses somehow (not deterministic when this happens).You might have beed in the similar situation .. Is is a hardware or software issue?Any idea what I could do to isolate the issue further?
CSD Replacement sugestions - Page 1
Forum section: electronics / projects

author: SoundLockEng
author_rank: Contributor
timestamp: September 29, 2020, 05:51:54 pm
content: Hi all,I have been working on a power supply and come across a failed part that is as it would seem completely unobtanium.the datasheet for the diode is attached it is a CSD part CSD2V10. I cant get hold of this part at all and so was wondering if i could replace it with a standard 4uS recovery time diode (with similar or better current and voltage rating). I don't have much experience of snubber network design.I found the datasheet a while ago but lost my record of the website it is from, it look a lot of hunting to find it!It is also being used in the same way to the circuit in the datasheet, though there are 3 diodes in parallel.maybe I should replace the snubber network all together?thanks for any advice as i am at a loss with this.Chris

author: Nataf
author_rank: Newbie
timestamp: October 06, 2025, 09:17:09 am
content: Hello Chris,just like you, I also encountered a similar problem in the Sony camera controller unit (CCU). I also found a shorted diode (out of the four diodes available) and only after much effort I was able to find the data that you also uploaded. At Sony's service, I was told that the part is no longer available and they also do not offer an alternative.I would be happy if you could help me and tell me which diode is recommended to install in place of the one that was shorted.Many thanks in advance.Nataf

author: kite31
author_rank: Regular Contributor
timestamp: October 06, 2025, 09:38:55 am
content: Nataf, that post was in 2020 and SoundLockEng has not been active on the forum for four years. Do you have any other information about your circuit or problematic diode? Can you show the good ones?
Progamable dso v cro - Page 1
Forum section: electronics / projects

author: m3vuv
author_rank: Super Contributor
timestamp: August 31, 2020, 03:12:16 pm
content: hi all,ive a kenwood DCS-8200,also a tek 453 scopes,both 50mhz,just wondered wha the differences are to use these,sort of a comparison,any ideas,i havent a clue,cheers in advance,m3vuv

author: Gyro
author_rank: Super Contributor
timestamp: August 31, 2020, 07:22:49 pm
content: If you have both of them, can't you tell?

author: Pawelr98
author_rank: Regular Contributor
timestamp: September 01, 2020, 01:05:25 am
content: 453 is an older scope, still using tube rectifiers for HV.The rest is transistors. Doesn't even use integrated circuits.Some early versions used Nuvistor tubes as well.Kenwood is a far more modern thing.Has an ADC, can store data and display it on the screen as well as performing many other things.But otherwise it also works as a normal analog scope.The manual is on the first page in google if you search for this model.
CSR8645 HFP and caller ID - Page 1
Forum section: electronics / projects

author: mckey128
author_rank: Newbie
timestamp: April 23, 2019, 09:38:27 pm
content: Hi all,I have been reading almost allhttps://www.eevblog.com/forum/projects/programming-off-the-shelf-csr8635-module/?alland after bricking and unbricking the device I am pretty good at playing around with that chipset.I have a question related to the HFP profile as I am trying to build up my own hand free set and I wish to get the caller ID when sb is calling me. I have tried to configure caller ID and the other options in the configuration tool but I cannot get anything out of it. I have a V 3.2 board and it seems like the UART is disconnected and I dont know where to get the caller ID from. I've also tried to change the UART Pin 000e and 000f (RX-PIO14 and TX-PIO15) as mentioned on the official datasheet at page 30 but still nothing.Am I doing something wrong?Any tip will be highly appreciated.

author: Whales
author_rank: Super Contributor
timestamp: April 23, 2019, 10:25:14 pm
content: You mentioned UART. Obligatory: have you tried reversing RX and TX? Are the UART pins being weakly held high by the board (they should be)? Have you tried a different USB UART device in case yours is cooked? Scoped the UART lines?

author: Buriedcode
author_rank: Super Contributor
timestamp: April 24, 2019, 01:57:07 am
content: As far as I am aware, the UART is permanently disabled in that device's ROM. It's annoying, as we can only configure things the firmware/ROM uses.

author: mckey128
author_rank: Newbie
timestamp: April 24, 2019, 02:49:55 pm
content: I have tried both ways in switching between RX and TX but not results. Look at the public datasheets the UART is accessible and it can be multiplexed with PIO 0 and PIO 1 or PIO14 and PIO15. As in the module the PIO14 and PIO15 are apparently connected I changed them in the Configuration Tool.So far I dont see any signal with the oscilloscope. By far the most logic usage for the UART is the ascii output of functional or either debug features such as caller id and such.Where should data out from the module when the HFP Caller ID is falgged on?This is my question....

author: Buriedcode
author_rank: Super Contributor
timestamp: April 24, 2019, 03:04:16 pm
content: The datasheet provides details on the hardware, but it is a ROM device, its "firmware" is fixed (some devices load firmware from external flash), and the most common form does not use the UART. Applications that use this device and use the UART have customized ROM, but I have yet to see one of those available as a module. Maybe try and find an existing product that has caller ID functionality, and uses this device? There may be UART functionality on the newer CSRA64215 but I do not know if this involves caller ID.
CSR8675 Bluetooth Audio - aptX Enabling? - Page 1
Forum section: electronics / projects

author: ssashton
author_rank: Frequent Contributor
timestamp: September 12, 2019, 11:28:42 am
content: Hi guys and gals,I purchased a number of CSR8675 bluetooth audio modules but they will not switch to using the aptX codec. They are stuck using SBC.I have confirmed it is not a problem with my phone as I can use aptX on other bluetooth receivers. I can see the codec being used in the android developer menu.Is there some kind of firmware setting that needs to be enabled to activate aptX mode?Anybody got experience programming these chips?Thanks!

author: ssashton
author_rank: Frequent Contributor
timestamp: October 02, 2019, 10:56:30 pm
content: Just thought I'd follow up on this. Turns out you need an aptX key loaded in the firmware.

author: Buriedcode
author_rank: Super Contributor
timestamp: October 03, 2019, 01:19:27 pm
content: Yes, these are often ROM devices, with external EEPROM for settings. This means you cannot change the firmware, so if it doesn't have Apt-X enabled in the firmware, you can't use it.If however, the module has >4MB flash instead of the EEPROM, then it might be possible to change the firmware, but as you found out the Apt-X is licensed, and so requires a key to use it in the IDE.
CSRA64215 bluetooth module potentially bricked - Page 1
Forum section: electronics / projects

author: WLA
author_rank: Newbie
timestamp: June 05, 2020, 07:15:47 pm
content: Hi Folks,first of all hello to everyone on the forum - a newbie hereI'm tinkering with various electronics. Recently I took a challenge of repairng a decent Bluetooth headset and decided to use one of CSR modules. I managed to go through the hassle of getting it to talk to the FT232RL and after getting it to link, I made backups as usually advised in such cases.Then I started playing around with settings for the csra64215. It came with no DAC setting so I took care of that, but while tinkering with event/button settings, I changed events for power on and power off...and now I'm in a bit of trouble.The thing does not turn on at all, PST does not see it, no LED activity, etc.All I did was to set Power Off and Power On events to Logical input ID 1 (which is a MFB line / PIO18).Any idea how to make it boot again?If I could only make it to force-start, I'd load the backup, but since I get no power/comms, I'm stuckLooking forward to all suggestionsCheersWL

author: WLA
author_rank: Newbie
timestamp: June 06, 2020, 08:52:55 am
content: Hi FolksThere is some good news! I think I managed to un-brick it.Had an epiphany while trying to sleepThe trick that came to my mind was to block external eeprom by grounding the "hold" input of the on-board 25u8033e for the boot-up phase. This prevented loading the problematic event setting and the module booted "clean". Then I let go of the eeprom input, linked the programmer and set the things to previous state.Ummmph... I was afraid this thing is a toast.Now, do you happen to know a good setting guideline I could use to use an input for standby or power on/off function?The charging circuit does not work yet either. Any ideas what needs to be set in the CSRA to make it work on 5V external power and charge the battery on VBAT line?Cheers

author: Buriedcode
author_rank: Super Contributor
timestamp: June 07, 2020, 03:23:24 am
content: As far as I am aware, the CSRA64215 ROM uses the multifunction button (MFB) for powering up/down. It is sometimes call the VREG_EN as it initially enables the onboard regulators. This is the only way to power up/down the module, but I believe you can change the config to change the time taken to hold the button down to do so. (because each button can have multiple functions depending on how long it is held for).I'm not sure what software you have, but this page appears to have the version I use:https://www.diyaudio.com/forums/digital-source/323164-program-csra64215-rom-15-csra64xxx-v2-3.html
CSRA64215 pairing with button: device can't be found - Page 1
Forum section: electronics / projects

author: jmibk
author_rank: Regular Contributor
timestamp: October 16, 2020, 06:20:22 pm
content: Hi,I'm doing some tries with a CSRA64215 module that I want to use as a BT to I2S device because it says, that it supports AptX lossless audio.The default setting of the modules is that pairing can be done on every situation without any time limitations. In short, you can hijack the audio output.So, I twiddled around with the PIO pins and these mappings, that I can start the pairing mode by applying 3,3V to pin PIO18.Now the problem: The CSRA64215 goes into pairing mode after a few seconds after powering it on. My mobile and a iPad can find the bluetooth device and they are also able to connect to it.After 20 secs the CSRA64215 goes into whatever standby mode ("Connectable"). After setting the PIO18 pin high a second (approx) it goes back into pairing mode (the fast flashing led shows pairing mode).During that pairing, none of my bt enabled devices can't find the CSRA64215 anymore (they are not currently connected to the CSRA64215, so that they behave like "new" fresh devices).Anyone any idea whats going wrong?Here some screenshots of the CSRA tool:Showing the behavior on power on - during that period it shows up in the bt list of devices.Showing the 20secs timeout.The connection of the button with the pairing mode (this works well).Here's the file dump of the CSRA64215.http://www.audiowerk.at/downloads/temp/eev/csra64215/20201016_5_dump.psrIf you need more information, please ask.
CSV waveform input in LT Spice? - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: August 16, 2017, 12:19:11 am
content: I have some unusual waveforms coming out of a sensor that require double sampling. If I capture a period on my scope, is there a way to use this CSV file as an input in SPICE.

author: f5r5e5d
author_rank: Frequent Contributor
timestamp: August 16, 2017, 01:28:17 am
content: LTspice has .wav file i/o - several free math sw can do the conversion - Matlab/Octave, SciLab, Python libs (scipy)...

author: Ian.M
author_rank: Super Contributor
timestamp: August 16, 2017, 03:38:45 am
content: LTspice voltage and current sources can accept data for a PWL waveform from a text file. The data file must be composed oftime source_valuepairs, one pair per line starting from time 0. Seehttp://www.simonbramble.co.uk/lt_spice/ltspice_lt_spice_tutorial_5.htm. There's an undocmented extension to the PWL format - times prefixed by+are relative to the previous time so if you have a data set sampled at a regular interval you can just stick+intervalat the beginning of every data line except the first, so you don't have to calculate the time of each sample to generate the PWL file.

author: Gary350z
author_rank: Regular Contributor
timestamp: August 16, 2017, 09:53:28 pm
content: Quote from: Ian.M on August 16, 2017, 03:38:45 amThe link doesn't work, below is fixed link:http://www.simonbramble.co.uk/lt_spice/ltspice_lt_spice_tutorial_5.htm
CT with two independent secondary windings - Page 1
Forum section: electronics / projects

author: floobydust
author_rank: Super Contributor
timestamp: February 03, 2016, 03:22:32 am
content: I have a CT with two independent secondary windings, used for GFC sensing.I'm not sure what happens if I have a burden resistor on one as compared to both windings.Sec. #1 1,000T winding has a 400R burden resistor and is used to detect mA of ground fault.Sec. #2 100T winding has a 100R burden resistor and mA of AC current is injected to test the GFC trip circuit.Both the load and return wire pass through the CT.With a burden resistor on Sec. #1, and no burden resistor on Sec. #2, I'm not sure if each winding is acting as a current source? That would make Sec. #2 put out a huge voltage.Or having a burden resistor on Sec. #2 would load down the output for Sec. #1?

author: coppice
author_rank: Super Contributor
timestamp: February 03, 2016, 03:31:36 am
content: Without a burden resistor a theoretical CT would have infinite voltage across it when current flows in the primary, as it is a current source. Even a real world CT can get up a pretty high voltage. The bottom line is don't operate CTs without a load in place. If you don't care about the output, just short the winding. The recommended burden resistor is a maximum value. CTs are fine with values down to zero ohms.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 03, 2016, 05:09:01 am
content: The windings act in parallel.Tim

author: floobydust
author_rank: Super Contributor
timestamp: March 11, 2016, 04:18:18 am
content: A follow up, after bench testing the CT, it is not making sense for how two windings interact.5A in, and get 4.55mA on 1000:1 winding, and 1.91mA on 100:1 winding; total 4.74mA; fine with some losses.Open circuit one burden resistor (R2) and 13% more voltage on the open 100:1 winding, and get 4.70mA on 1000:1 winding.Low value one burden resistor (R2 4.4R) get 3.12mA on 1000:1 winding, and 17.5mA on 100:1 winding; total 4.88mA;It looks like total reflected current (summation of both windings) stays about constant?

author: coppice
author_rank: Super Contributor
timestamp: March 11, 2016, 07:23:12 am
content: You have used very big resistor values. CTs are rather imperfect as current sources. They only behave close to a true current source when the burden resistor is just a few ohms. Try putting 10 ohms across each winding, and see how well it behaves.
Curious... How does the BIOS know how much memory is installed? - Page 1
Forum section: electronics / projects

author: MarkS
author_rank: Unknown
timestamp: February 04, 2012, 09:35:32 pm
content: This is something that I never understood. How does the BIOS know (I assume that the OS gets this info from the BIOS) how much is installed? Is there something about the wiring on the actual sticks that tells the total size per stick? I know that DRAM chips don't expose this info and it isn't exposed with the way the memory is addressed.Something on the sticks must report this information? Correct?

author: Short Circuit
author_rank: Frequent Contributor
timestamp: February 04, 2012, 09:53:08 pm
content: correct.http://en.wikipedia.org/wiki/Serial_presence_detect

author: MarkS
author_rank: Unknown
timestamp: February 04, 2012, 09:59:12 pm
content: Thank you.
µCurrent 3D case - Page 1
Forum section: electronics / projects

author: EEVblog
author_rank: Unknown
timestamp: July 15, 2012, 11:14:41 pm
content: Charles at Makerbot has designed this nifty 3D printed case for the uCurrent.http://www.thingiverse.com/thing:26878Dave.

author: dda
author_rank: Contributor
timestamp: July 16, 2012, 12:59:38 am
content: What's the cost of the plastic filament used to make something like this compared with a jiffy box?

author: EEVblog
author_rank: Unknown
timestamp: July 16, 2012, 01:03:09 am
content: Quote from: dda on July 16, 2012, 12:59:38 amThe Jiffy box is $1.80 trade, or about $1.20 wholesale + GST.Would be interesting to run the numbers to find out...Dave.

author: dbinokc
author_rank: Contributor
timestamp: July 16, 2012, 01:26:34 am
content: A spool of filament runs about $50(US)/kilogram or $1.42/ounce and the print quality is not going to be quite that great because of the layers. So you would not come out that far ahead in that respect.Where the value comes in, is the ability to create exactly what you want and to not have to wait on shipping.

author: IanB
author_rank: Super Contributor
timestamp: July 16, 2012, 01:39:40 am
content: "Please excuse the print quality. The enclosure was printed on a highly uncalibrated machine with experimental parts."Hate to be a skeptic, but doesn't that apply to every Makerbot on the planet?I have to presume that the Makerbot is designed as a personal device for one-off prototypes. I don't see how it can work for production parts. So the cost/benefit equation if you consider buying one is based on the value to you of making things for yourself that otherwise would be difficult to make. But then I also have to wonder how it compares to the greater flexibility of a shop equipped for cutting, milling, drilling and gluing?

author: EEVblog
author_rank: Unknown
timestamp: July 16, 2012, 01:42:28 am
content: Quote from: dbinokc on July 16, 2012, 01:26:34 amYes, you'd be crazy to do it for cost reasons. Listen to today's AmpHour for talk about the Ninja Block cases.Would be interesting to know how much it costs in comparison though.The jiffy box weights 36g with lid, so assuming the printed one is say 30g, that works out at roughly a similar cost.Dave.
current and voltage sensing with minimal power comsumption - Page 1
Forum section: electronics / projects

author: --badcab1e--
author_rank: Newbie
timestamp: September 18, 2018, 06:28:07 pm
content: Hi all,I'm more of the Software kind, but I have now found my way into some Hardware design...So I have a Question and maybe someone could help me.I am designing a battery powered PSU with 3 Buck/Boost converters. One for the MCU and two with adjustable voltage and current(with up to 5A continuous current).So now I'm looking for a solution to measure current and voltage as efficient as possible (Active cooling of the Rsense is not Possible) and the whole thing is battery powered. A resolution of about 100mA would already make me happy.I haven't found any interesting Application Note, so I would greatly appreciate any help pointing me in the right direction.

author: rx8pilot
author_rank: Super Contributor
timestamp: September 18, 2018, 06:38:06 pm
content: Something like a TI INA226 is not a bad option. It outputs data over I2C, has internal 16bit A/D and programmable filtering and resolution. The Rsense can be extremely low value to the point where heat is not a practical concern.
Current and  - Page 1
Forum section: electronics / projects

author: getfast_kiran
author_rank: Regular Contributor
timestamp: June 04, 2018, 07:27:55 am
content: Current Configuration:CT transformer config : 50A :330mVACMake : ElMeasureType : SplitCoreProblem definition:I am not getting current reading alone in Schneider Energy meter from Split core CT while I could get the result from a normal type CT of60:5 Ratio of Class 6 of powering 5VA connected to the same energy meter.Initially I thought it would be because of the Splitcore CT not being able to drive the Schneider meter CT input. Hence I tried to build a Voltageamplifier and current amplifier like as depicted in the drawing I attached but still the meter is showing zero. I am not sure about the working ofamplifier is correct or not is apt for the situation, Kindly let me know how can I correct it to get output from splitcore CT to drive the schneider meter input.Can any of you tell me why Energy metering is not working when using spiltcore CT and is working when using a closed CT.Photos of the circuit are attached. Kindly do take a look and help me with the same if you know about the same. Thanks in advance

author: Jeroen3
author_rank: Super Contributor
timestamp: June 04, 2018, 08:00:44 am
content: Is the split core aRogowski coil?Also, there are no photos or any device specifications. Add those important details to the question.

author: rstofer
author_rank: Super Contributor
timestamp: June 05, 2018, 02:31:01 am
content: It sounds like your transformer is current -> voltage. A current transformer normally converts primary current to secondary current, usually 5A. The open circuit output secondary voltage of a current transformer approaches infinity for a very short time before everything burns up. That's why you need to be so very careful that the secondary circuit is never open. You would be trying to push a current of up to 5A through essentially infinite resistance. Voltage will follow...The secondary current flows through a low value resistor in the metering device called a 'burden' and the voltage drop is measured for metering.See page 3 here:https://www.bpa.gov/transmission/Doing%20Business/Interconnection/Documents/metering_application_guide.pdfYou didn't provide a link to the meter, all of the above applies to standard metering but I have no idea what your gadget does.
current boost amplifier better performance running hot? - Page 1
Forum section: electronics / projects

author: SArepairman
author_rank: Frequent Contributor
timestamp: September 16, 2013, 08:44:29 am
content: What does positive saturation voltage specification mean?I see a curve showing me that under a heavy load and higher temperature the saturation voltage for a particular amplifier is higher.If I understand this correctly this amplifier will be able to use a greater voltage if it is running hot (120C) and under a heavy load then it does running under a light load at a reasonable temperature.wtf? I figure it would be the inverse. Why does its saturation voltage increase as the stress it is placed under increases?

author: Bertho
author_rank: Regular Contributor
timestamp: September 16, 2013, 08:58:10 am
content: Quote from: SArepairman on September 16, 2013, 08:44:29 amI guess it refers to the saturation voltage of the active component(s). It is usual that the voltage drop over transistors rises with temperature (bipolar Vce-sat rises or mosfet Rds-on rises). That means that the component's dissipation increases at constant load. Increased dissipation lets the temperature rise further and at some stage you have a run-away process that burns out the component if not compensated.
Current booster questions (updating components) - Page 1
Forum section: electronics / projects

author: randomOracle
author_rank: Contributor
timestamp: October 02, 2021, 02:28:54 pm
content: Hi everyone,A while back I found the attached circuit and I can't figure out how to redesign/adapt the circuit. The components being used are relatively old and I 'just' wanted to replace unavailable components with newer ones, otherwise looking for a similar performance. I do not fully understand how the circuit works, but it seems to me that R1 and R2 'somehow' are selected such that the transistors are off when the OPAMP is not pulling any current -- they only switch on once the OPAMP actually starts working. All the calculations I came up with lead to inconclusive results though.Perhaps someone is able to explain to me how R1 and R2 were computed for the specific example, such that adapting the values for other opamps, and especially transistors, is possible?Thank you.

author: Terry Bites
author_rank: Super Contributor
timestamp: October 02, 2021, 05:02:54 pm
content: The LT1210 is a monster.We've been here before..https://www.eevblog.com/forum/beginners/non-standard-op-amp-configuration/https://www.eevblog.com/forum/projects/push-pull-output-stage-1m$-question/When the opamp current its output current is greater than about Vbe/6.2 the power transistors turn on supplying more current into the load. A short circuit limit set by the emitter resistors and the flames around them.WRT to current limiting this circuit is poor.The quiescent current of the opamp has little effect. Just choose your to create a Vbe at a point below the current limit of the opamp and off you go. If you use Darlington's you'll need to generate 2xVbe. Dont try this circuit with MOSFETS!!

author: randomOracle
author_rank: Contributor
timestamp: October 02, 2021, 05:36:59 pm
content: so just to confirm this: so Vbe is around 1.0-1.2V (depending on current) according to the datasheet, so 1V / 6.2R = 160 mA; thank you!most other transistors I checked would work well with the 6.2R, too; nice.

author: David Hess
author_rank: Super Contributor
timestamp: October 02, 2021, 11:25:10 pm
content: The D44VH4 and D45VH4 are part of an old series of ring emitter transistors which are still produced in the form of the D44 and D45 series and replaced by the D44VH10/D45VH10 or D44H11/D45H11 if slightly lower power is acceptable. These transistors would still be my first choice unless lower power is acceptable.

author: David Hess
author_rank: Super Contributor
timestamp: October 02, 2021, 11:26:27 pm
content: Quote from: randomOracle on October 02, 2021, 05:36:59 pmThat is the saturated Vbe. In practice it will be more like 0.8 volts but the values are not critical for proper operation.
Current clamp with noise filtering capacitors - Page 1
Forum section: electronics / projects

author: Faringdon
author_rank: Super Contributor
timestamp: August 26, 2023, 01:43:06 pm
content: Hi,Please imagine you have been given a crowded PCB layout which comprises the attached Current Clamp circuit. (jpeg and LTspice) The sense resistor is some 5cm away from the opamp, and in the short given time that you have, bringing that nearer to the opamp will not be possible.As such, I assume that you would want to be sure that as much as possible, the sense resistor gets “diff pair” routed back to the opamp?Also, the schematic shows six ringed noise mitigation capacitors. Supposing that you can only use 1 of them. Which one would you choose?Now say you are allowed two of them….which two would you choose?(BTW, the 1.25V reference is also some 6cm away from the opamp.)

author: magic
author_rank: Super Contributor
timestamp: August 26, 2023, 01:54:00 pm
content: C4 seems the least harmful, unless it causes the LT1389 to oscillate.

author: Faringdon
author_rank: Super Contributor
timestamp: August 26, 2023, 04:36:05 pm
content: QuoteThanks, regarding C4, thats the one that i also thought should really be there, and not an option...but on this tight board, its difficult.I reckon the other one should be C6..would you agree?To be honest, i think all the ringed ones should be in there....but we dont have room.C2 looks like a potential problem....it is pretty well direct from opamp output to rail, which is a no-can-do with many opamps.Ayk, the cct is a bog standard current clamp , usually seen with NPN and coming off ground instead.
current consumption deviation across multiple devices - Page 1
Forum section: electronics / projects

author: imagiko
author_rank: Newbie
timestamp: June 07, 2019, 03:18:38 am
content: I am testing some BLE based beacons powered off of a coin cell 2032. Most of the devices work as expected within their current range, but a few I'd say 10% die within a couple of weeks or so(when they are supposed to last atleast a year). I am trying to figure out why these devices are consuming more power compared to others. What should I try to do? I am not exactly a hardware engineer so I am not very familiar with debugging techniques in hardware. It could be bad caps, assembly flaw - what's a good way to start analysing this? I don't think it is a software problem as it would have manifested on all my devices, not just a few. FWIW there is a 100uF cap across the battery.
Current consumption - Page 1
Forum section: electronics / projects

author: fedimakni
author_rank: Regular Contributor
timestamp: April 15, 2021, 04:37:15 am
content: Hello,Currently i designed a battery power device and i made around 100 pcs. By measuring the power consumption i noticed that it consumes apprx from 6uA to 20uA in sleep mode. My question is why some devices consumes 6uA in sleep mode other consumes 13uA and other consumes 20uA while all devices have same component same software.I know that there are leakage current for example capacitor and they are different by not as much as 3 times more for average values.Thank you very much for your support

author: james_s
author_rank: Super Contributor
timestamp: April 15, 2021, 05:43:24 am
content: Are you using good parts from known reputable suppliers? Random cheap parts can be counterfeit or way off from the published specs. Is there conductive flux or other contamination on the PCB? You might try removing parts and checking the current, find out if it's something like a voltage regulator, leaky capacitor or the microcontroller causing the current draw.

author: David Hess
author_rank: Super Contributor
timestamp: April 16, 2021, 02:39:35 am
content: Standby current for some ICs can vary that much.

author: Miti
author_rank: Super Contributor
timestamp: April 16, 2021, 03:05:07 am
content: Quote from: fedimakni on April 15, 2021, 04:37:15 amWhat parts are you using? Maybe the maximum sleep current is 20uA and you’re just lucky that some take only 6uA.
Current control and more for lead acid battery charger - Page 1
Forum section: electronics / projects

author: okw
author_rank: Frequent Contributor
timestamp: December 26, 2023, 02:14:29 am
content: Hello! I'm making my own lead acid charger (6V and 12V, max 4A). I know there exist plenty of example designs, but I wanna do it myself (for the learning, and the customisation).Input will be from a clean 20V DC supply I have, and charge voltage will be regulated with a switch mode step-down.I'll start with the most important question, how to adjust current? I've attached a schematic of two N-channel MOSFETs and a digital pot (drawn as a resistor for now). Will this work? And how to calculate resistor value based on how much current I want to pass through? Are there better ways than this? I could of course replace the pot with 2-3 resistors and transistors to have fixed charge levels (e.g. 0.2A / 1A and 4A), but it would be sweet to be able to adjust over the full range. I think maybe put PWM + fixed resistor could do the trick, instead of potmeter tied to 3.3v?I see most lead acid charger schematics are based on linear regulators, but are there any drawbacks of using switch mode regulators (except complexity and cost)?Anything I should take into consideration, avoid or pay attention to? I've designed a few DC-DC circuits before (but only as power supplies, not chargers).It shall also monitor both input and charge voltage and current, as well as adjust charging (voltage and current). Adjustments shall be done from an ESP32.I've used dedicated current monitors like INA219 in the past, but this time I would like to play around with opamps. I'll chose a dual opamp with input offset of 1-1.5mV (or better). That's Ok for rough current measurements? How do I choose the proper resistors? I have now (for charging opamp) 1k/13k which gives me 2.912V when 4A passes the 56mR shunt (if I'm not mistaken). Should I choose higher/lower resistors (less parasitics vs more noise resistant)?I can adjust the voltage by connecting a digital potentiometer as feedback resistor on a very simple and cheap DC-DC buck. The only thing that would differ between 6.8V and 13.6V output is the inductor. And 95% of the times, I'll charge 12V batteries anyway, so I probably choose an inductor for this output(?).
Current Control circuit for High Power LED - Page 1
Forum section: electronics / projects

author: samk
author_rank: Newbie
timestamp: November 27, 2017, 10:59:41 pm
content: Specs of LED(BXRA-56C5300H 50W) are 23.5 Vf and 2.1 A typical current.Led max rated current is 4 A @ 28.5 V only for pusling at 10% duty cycle.My actual project has 64 such LEDs and will be powered with 24 V 67 A DC supply to 32 such LEDS so equivalent 2.09 A current for each LED string connected in parallel to supply.I want the LED should be operating at this rated current of 2.1 A for 99% of time and must be able to switch (digitally controllable) must draw 4A with 10% duty cycle and switch back to regular 2.1 A current.I do have heatsinks for these LEDs as they will be dissipating lot of heat. Can anyone suggest me circuit for this and explain .Thank you!
current driver is saturated problem - Page 1
Forum section: electronics / projects

author: john23
author_rank: Frequent Contributor
timestamp: May 31, 2025, 12:59:41 pm
content: Hello ,I have built a PID controller which is connected to differential driver by the manuals below.The PID is single ended while the driver is differential so I connected the two using converter.The key component is the integrator.I want that the driver to create a current on the load so It will be following the integrator output signal.However as you can see that as integrator output rises the driver current saturated as some point .Is there a way to fix the driver so it wont sature so quickly?Ltspice files are attached.https://www.analog.com/en/resources...ne-driver-receiver-design-guide-part-two.htmlhttps://www.analog.com/en/resources...n-single-ended-to-differential-converter.html
current feedback op-amp recommendation ? - Page 1
Forum section: electronics / projects

author: jmelson
author_rank: Super Contributor
timestamp: July 16, 2020, 07:40:12 pm
content: We have been using the AD8002 in some nuclear detector preamplifer circuits, and they work quite well. Can anybody recommend one that has more output current? The AD8002 is rated at 70 mA and does clip at about that level. Is there a similar amp that can go to 100 - 120 mA output? We need pretty fast risetimes in the 4-6 ns range, and may have to feed dual 50 Ohm loads with several Volt signals. In this particular case, we don't need much amplification, but we need jumper-selectable inversion.Thanks in advance for any suggestions.Jon

author: ni.st
author_rank: Newbie
timestamp: July 17, 2020, 10:50:22 am
content: What about the AD8009? I have used it to feed dual 50 Ohm loads, because it can deliver up to 175 mA. A downside would be, that it is not available in a dual package.

author: OM222O
author_rank: Frequent Contributor
timestamp: July 17, 2020, 01:26:33 pm
content: The usual solution to that is to follow the op amp with a class A or AB amplifier (depending on power dissipation, crossover distortion, etc). Op amps aren't really meant to drive "high" currents (more than ~20mA) and your selection becomes very limited if you want to choose a high current op amp.

author: jmelson
author_rank: Super Contributor
timestamp: July 17, 2020, 01:50:17 pm
content: NI.ST, thanks, I will look at the 8009. Single channel part may offer advantages!OM2220, thanks, I have used the Harris HA9P5002 buffer after a current feedback op amp with good results, but we need 4 ns rise and fall times here, and I don't think it can do that.Jon

author: E-Design
author_rank: Regular Contributor
timestamp: July 17, 2020, 02:15:59 pm
content: Quote from: jmelson on July 16, 2020, 07:40:12 pmSince you only need to roughly double your output current, is there a way you can parallel share (ballast) two AD8002, preserving your speed characteristics while doubling the drive capability.?

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 17, 2020, 02:43:41 pm
content: Quote from: jmelson on July 16, 2020, 07:40:12 pmwhat voltage swing range are we talking about? different swing, different slewrate requirement. opamp gives slewrate spec, not rise time. is 600MHz -3dB BW important? what nature of signal, repetitive? at what max repetitive frequency?digikey searchymmv.

author: awallin
author_rank: Frequent Contributor
timestamp: July 17, 2020, 05:11:04 pm
content: LMH6702 works well for e.g. 10MHz distributionhttps://www.ti.com/lit/ds/symlink/lmh6702.pdfmaybe two of them in parallel if you need more current?
Current for a buck boost converter. - Page 1
Forum section: electronics / projects

author: Siddhat
author_rank: Regular Contributor
timestamp: May 03, 2020, 06:18:19 am
content: Hey everyone,I just finished designing a buck boost converter. The converter is implementing a Maximum Power Point Tracking (MPPT) algorithm at its input. Now I would like to charge a 12 Volts lead-acid battery with the buck-boost. The voltage at the output of the converter is held by the voltage of thelead-acid battery. But in order to charge the battery properly, the current into the battery from the converter is to be controlled.I could not figure out a way to control the output current of the converter. How can the current be controlled?

author: Vovk_Z
author_rank: Super Contributor
timestamp: May 03, 2020, 09:48:21 am
content: We change the charging current by changing the output voltage. If current is too large - lover the voltage and vice versa. The limits of charging voltage are somewere in between 12V - 16 V (it depends on additional parameters).

author: Ian.M
author_rank: Super Contributor
timestamp: May 03, 2020, 11:30:50 am
content: You cant control the output current independently if you are running MPPT at the input - the system is over constrained and cannot magically make the input power different from the output power + losses. However you can and should implement output current and voltage limiting. If either limit is exceeded it should drop out of MPPT mode. For lead acid battery charging applications the voltage limit should be temperature compensated, and its advantageous to track charging/discharging history and state of charge with a MCU so it can vary the limits to run a more effective lead-acid charging algorithm and reduce wear on the battery.How to implement that lot is highly dependent on your buck-boost topology, and whether you have built the controller from scratch or are using off the shelf controller ICs.
Current "goto" PCB suppliers - Page 1
Forum section: electronics / projects

author: perdrix
author_rank: Frequent Contributor
timestamp: August 11, 2025, 11:01:11 am
content: I have a 150mm x 160mm four layer board that I want a few of made up.JLCPCB don't to between pad solder mask on "prototype" boards which for me is a bit of a "no-no", and getting 3-5 boards made on their production service is quite a lot more spendy (about $100 for prototype boards, about $160 for the standard service).Who do folks recommend these days - target is 8/8 rules, 4 layer, ENIG preferred over HASL/LF-HASL.Price is fairly important ...Thanks, David
Current Induced in a Coil of N Loops - Page 1
Forum section: electronics / projects

author: Chet T16
author_rank: Frequent Contributor
timestamp: November 12, 2011, 08:16:01 pm
content: I'm doing a presentation on RFID for university and i've been poking around my RFID reader and oscilloscope.I decided to see if i could detect the alternating field by attaching the ground clip to the end of the probe and sure enough it worked. Going back to faraday i tried making an antenna and compared the voltages against the number of turnsvoltage on the Y, turns on the XSo the theory tells us it should be proportional to N which obviously isn't the case here. I didn't have any thin wire so i used single core hookup wire. Is the non-linear result because of the thinkness of the wire or because the readers field isn't strong enough or both? Also do the loops need to be tight? i.e. together, not the radius

author: IanB
author_rank: Super Contributor
timestamp: November 12, 2011, 09:34:37 pm
content: I'm no EE, but with RF things aren't so simple. You are getting into antenna design theory, where resonance and capacitance effects come into play.For instance if you place the turns of the coil close together you introduce some parasitic capacitance between adjacent turns that can have a negative impact on performance. That's why some RF coils are deliberately made with a spacing between adjacent turns rather than winding them next to each other.

author: Zad
author_rank: Super Contributor
timestamp: November 12, 2011, 10:06:36 pm
content: Flip the graph horizontally, and you have a classic power transfer graph. You will remember that for maximum power transfer, the impedance of a load will equal the impedance of the source. You have found that the characteristic impedance is achieved at around 3 or 4 turns.http://en.wikipedia.org/wiki/Maximum_power_transfer_theorem

author: slateraptor
author_rank: Frequent Contributor
timestamp: November 13, 2011, 10:54:59 am
content: Quote from: Zad on November 12, 2011, 10:06:36 pmNice observation.

author: Chet T16
author_rank: Frequent Contributor
timestamp: November 13, 2011, 11:28:38 am
content: Quote from: slateraptor on November 13, 2011, 10:54:59 amIndeed!I've flipped the graph now, it gives me something nice to point out.
Current limit circuit - Page 1
Forum section: electronics / projects

author: PULSSAIR
author_rank: Contributor
timestamp: September 25, 2018, 06:27:05 pm
content: Hello guys and girls, I am working on a project to design a simple current limit(hardware select between 2.2A and 2.5A). I have come up with an opamp design and I would like some feedback. Below is attached the circuit(simulation in LTSpice). Let me know what you think about it.

author: Zero999
author_rank: Super Contributor
timestamp: September 26, 2018, 08:21:20 am
content: Quote from: PULSSAIR on September 25, 2018, 06:27:05 pmIt appears to be oscillating. There's also quite a lot of voltage drop, as the output MOSFET is working as a source follower.Please attach the .asc file here.

author: snarkysparky
author_rank: Frequent Contributor
timestamp: September 26, 2018, 02:41:44 pm
content: I would add 1nf across R4 and a resistor from base of Q1 to ground to reduce the gain of that stage.
current limit design question - Page 1
Forum section: electronics / projects

author: ashochat
author_rank: Newbie
timestamp: December 26, 2015, 01:56:57 pm
content: Halo everybody,Can some one please advise where I can learn how to build current limiter circuit?Thanks

author: Zero999
author_rank: Super Contributor
timestamp: December 26, 2015, 04:03:17 pm
content: Please provide more information.If all you need is over-current protection then a PTC resistor (polyfuse) will do.A current source/sink can be made with the LM317, see the datasheet.
Current limited AC voltage source in LTSpice? - Page 1
Forum section: electronics / projects

author: 741
author_rank: Frequent Contributor
timestamp: August 02, 2024, 11:35:24 am
content: Any ideas folks?So far I've only tried a resistive divider of (say) 10:1 and scaling the source voltage accordingly.There is a DC version herehttps://electronics.stackexchange.com/questions/462819/ltspice-simulation-how-to-design-a-non-ideal-voltage-source-and-limit-its-curr

author: moffy
author_rank: Super Contributor
timestamp: August 02, 2024, 12:21:30 pm
content: You mean like:https://www.eevblog.com/forum/projects/ac-current-source-any-idea-for-soil-resistivity-purpose/msg5583583/#msg5583583?

author: 741
author_rank: Frequent Contributor
timestamp: August 04, 2024, 04:10:27 pm
content: Hi, Thanks for the pointer.I've just quickly scanned and it seems to resolve to a Howland source. Given I don't want to actually make the AC current source physically, I was wondering whether something simpler & neater could be cooked-up in "simulation land".

author: Overspeed
author_rank: Frequent Contributor
timestamp: August 04, 2024, 04:25:34 pm
content: Hellothe current ''problem'' is first what level of current you want / need as from nA to true full Amp level that not the same at all regarding the involved componentsRegardsOS

author: 741
author_rank: Frequent Contributor
timestamp: August 05, 2024, 09:00:45 am
content: This is simulation only - therefore, hopefully I can choose current at will.For example 10A, 10V, 10kHz (or whatever). Like a normal "Voltage" part, but with a current limit.