hybridfree/eevblog-posts huggingface dataset:
DC/DC solution for +-15V from 9-12V DC input - Page 1
Forum section: electronics / beginners

author: belzrebuth
author_rank: Frequent Contributor
timestamp: May 09, 2024, 09:45:31 am
content: Hi all,I need to have a bipolar supply from a 9-12V source. up to 80mA output at each rail of the bipolar supply (maybe even less) is required.I've tried a TRACO TBA 2-1223 which fit the bill on paper but I was getting some ground hum at the output.I could try the bigger version TEC 3-0923 but I am already thinking this could get far more expensive than using a DC/DC converter IC and some passives.I've looked at various boards from aliexpress that have one or two chips and passives so ideally I'd like to do the same on my board but use a chip I can get from a reputable source like the TPS5430 or similar but I didn't seem to find any simple solution online for my application.I surely must be missing something..

author: CountChocula
author_rank: Unknown
timestamp: May 09, 2024, 11:34:16 am
content: What's your use case? The TBA 2-1223 has an unregulated output—that's probably why you were getting those strange results.If you want an off-the-shelf solution there are several (likethis one) that might fit the bill. You will want something that's regulated; the reason why I'm asking for the use case is that the ripple out of one of these modules (typically in the 10s of mVpp) may not be appropriate for your needs.If you want to go a more discrete route, there are a couple possibilities: boost your positive voltage up to +15V, then use a charge pump to generate a -15V rail (though this will usually only be good up to ~10mA, and you will still have to contend with significant ripple). Alternatively, look up “rail splitter” circuits; you boost your input voltage to 2x Vout (so, 30V in your case), and then create a new virtual ground at 15V, giving you both rails. These can be a little complex, but they can also be made to source significant amounts of current.—CC

author: rstofer
author_rank: Super Contributor
timestamp: May 09, 2024, 05:05:59 pm
content: Murata makes a lot of bipolar output DC-DC converters. Here's the Product Search page. Your input voltage may be too low for the devices I have seen but I've only looked at a couplehttps://www.murata.com/en-us/search/productsearch

author: Benta
author_rank: Super Contributor
timestamp: May 09, 2024, 06:22:41 pm
content: Use a Traco type with regulated outputs.
dc/dc step up converter - Page 1
Forum section: electronics / beginners

author: simondid
author_rank: Contributor
timestamp: May 09, 2017, 01:23:13 pm
content: heyso i'm looking for a dc/dc step up converter design which takes 3 to 6 volts and can output between 5 and 12 volts i need the design to be adjustable with a resistor.that input to this converter is a pin called IPSOUT from the C.h.i.p pro sbc witch has a 2.5 amp at up to 5v limit the pin is described as followinghttps://docs.getchip.com/chip_pro.html#battery-charging-and-bts-pinQuote

author: Zero999
author_rank: Super Contributor
timestamp: May 09, 2017, 06:00:42 pm
content: If you want to convert between 3V and 6V to 5V to 12V, then you'll need a DC-DC converter which can both step-up and step-down the voltage, since there's some overlap between the input and output voltages.

author: simondid
author_rank: Contributor
timestamp: May 10, 2017, 11:19:02 am
content: okay ya that makes sensealso, another question if you read the documentation do you read it like it can exceed 5 voltes?

author: rfbroadband
author_rank: Unknown
timestamp: May 15, 2017, 08:32:34 pm
content: a SEPIC converter will be able to meet your requirements.

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 16, 2017, 12:39:31 am
content: http://www.ebay.com.my/itm/DC-DC-Auto-Boost-Buck-step-Up-step-down-Converter-Module-Solar-Voltage-LM2577-/201422600692?hash=item2ee5b8f9f4:g:EKMAAOSwMmBV7EYq
DDR3 routing - Page 1
Forum section: electronics / beginners

author: subzero
author_rank: Newbie
timestamp: November 20, 2017, 03:09:01 am
content: Has anyone routed a DDR3 BGA to an Allwinner A13? I'm just learning how to do the routing between these two chips, and just wanted to ask a few questions. I have set up a mock test scenario (the signal paths between DDR3 BGA and the A13 processor), and came across something kind of annoying while routing the first data lane (DQ[0:7], DM0, DQS0+/DQS0-). The DM0 and DQS0+/DQS0- signals overlap while routing, which is a bit of a shame, because all of the data bits route nicely. What would designers usually do in this case? Route the DM0 signal on another layer, and leave the other signals on the top layer, or (as recommended in a lot of datasheets), route all the signals exactly the same? This seems to be the only problem, as the other data lane doesn't overlap at all, which would make it a bit of a shame if I had to route the lanes on different layers. I guess I could wrap the DM0 signal around the DQS0-/DQS0+ signals, but that seems... umm... I guess that could be done come to think of it.Ideas / recommendations? Tips for placing the decoupling capacitors? Tips for length tuning these signals? How would designers generally tune the data lanes? Waves, or by introducing longer lengths by hand?Thanks!

author: PhillyGreg
author_rank: Contributor
timestamp: November 20, 2017, 04:58:51 am
content: Do you have a screenshot showing both the processor and the RAM?A couple questions and a few thoughts that come to mind.How many layers are you targeting, and what are your design rules?What CAD and simulation tools do you have?What speed are you looking to run the memory at?Micron TN-41-13 is a pretty good reference if you haven't looked at it yet. (It has suggestions on placement for decoupling capacitors)Do you have any known working layouts for the A13 to reference?It can be best not to reinvent the wheel if you don't have to.Also looks like you are using a x16 chip. I'm wondering if the processor was setup for a clean layout with two x8 chips.

author: RoadRunner
author_rank: Frequent Contributor
timestamp: November 20, 2017, 10:30:07 am
content: yes i have done , here is the look at image from ddr3 routei have look closely where you are stuck.complete project lies herewww.circuitvalley.com/2015/11/linux-board-homemade-pcb-design-ddr3-schematic-altium.html
DE 5000 vs. LCR Research Pro1 Plus vs. Shannon Tweezers ST42 - Page 1
Forum section: electronics / beginners

author: ChrisEvo8
author_rank: Newbie
timestamp: March 15, 2023, 10:55:10 pm
content: I am new to SMD electronics and was looking to buy my first LCR meter. I'll be completely honest, I have a wide range of interests so I don't know of any specific metrics I NEED to be able to verify, but I was trying to find the best "general use" LCR that seems relatively affordable. After searching around on these forums it seems the DE-5000, LCR Research Pro 1 Plus and Shannon Tweezers ST42 would be some of the "best" three for an intro LCR although I'm open to suggestions.It seems to me that the DE-5000 might be the best overall budget LCR, but it seems like the two tweezer designs might be better at measuring components in board (not sure about this). Ideally I would like to have that ability, I know the 5000 has an tweezer connection you can add, but from what I understand the wire lengths of that attachment can affect measurements (correct me if I'm wrong about this).I already own a Fluke 117 and Siglent SDS1104X-E just as an FYI so I don't necessarily need this LCR to be good at larger values. Any advice is appreciated. Thank you.

author: thm_w
author_rank: Super Contributor
timestamp: March 15, 2023, 11:19:43 pm
content: What specifically are you using it for? Most likely DE-5000 is a good place to start.Or even one of those cheap arduino component testers if you don't need high accuracy for through hole stuff.Quote from: ChrisEvo8 on March 15, 2023, 10:55:10 pmYes you can add wired tweezers. You zero/cal out the tweezers before measuring any components if you are worried about the leads affecting the reading.

author: donlisms
author_rank: Frequent Contributor
timestamp: March 16, 2023, 08:15:06 am
content: Even non-tweezer leads can be an issue for the DE 5000, so calibration and lead considerations are always important.On the other hand, imagine a capacitor that isn't a cute tiny little thing on a nice clean, open, fully accessible circuit board on your desk. Maybe it's down inside, behind a Gizmo. Maybe it's not so tiny - maybe your thingamajig has a power supply made of big capacitors or something. It could spoil your entire evening if all you had was tweezers!Pros and cons, pros and cons. Hm. I would vote for reasonable flexibility - something with options - depending on how fuzzy your crystal ball is regarding what you'll need to do.Or just get one, and then the other if you find you need it.
De-embedding S-Parameters of a DUT from three-port baluns  - Page 1
Forum section: electronics / beginners

author: RFbeginner
author_rank: Newbie
timestamp: September 21, 2019, 06:18:32 pm
content: Hey everyone,I am currently trying to de-embedd a DUT that has on both sides of it 180° Hybrid BalunsI have the measured 2x2 S-parameters of the boards and I have the 3x3 S-parameters of the Hybrids. the constellation of the board is as follow :Hybrid(single-ended Input,Coupled Output)--DUT--Hybrid(Coupled Input, Single-ended output)I first tried to convert all the S Parameters to 4x4 matrices(filled with 0) and de-embedd the boards using the T parameters but it obviously didn't work due to the singularity of the matrices and the i tried to reduce the hybrid matrices to single ended input differential output and due to the fact that the common mode is negligible leaving the differential mode and he the Matrices become 2x2 and I tried to De-embedd the boards as shown in the picture attachedBut still the results are not satisfying at all, does anyone know if something is off in my try or does anyone have another advice on how to de-embedd the boards ?Thanks a lot
Dead Bug - Page 1
Forum section: electronics / beginners

author: mark4th
author_rank: Newbie
timestamp: February 21, 2015, 09:34:43 pm
content: just watched the dead bug video on youtube......and it occurred to me that there might be another way of doing this.1: Solder leads to each pad of bug and trim to a length longer than your going to need.2: Turn dead bug over, route each lead to the pad you want to solder it to and trim to length.3: Solder each lead to the pad you want it attached to.I can see that step 1 might be difficult with a chip that is not secured but you could use double sided goopy tape for that no? you can clean off the goop later

author: German_EE
author_rank: Super Contributor
timestamp: February 22, 2015, 09:37:51 am
content: I can see the point of your suggestion because by turning the chip over there is no longer a requirement to bend the wires down to the pads, good ideaI have been known to use a third alternative, instead of wiring to pads I use PCB pins (A.K.A. Veropins). After making the connection to the chip I wind a few turns of wire around the pin then solder, the wire I use has insulation which evaporates at soldering temperatures.

author: German_EE
author_rank: Super Contributor
timestamp: February 22, 2015, 03:45:38 pm
content: Yes, you read the original post correctly, dead bug with the chip connections downwards.
Dead Digital Voice Recorder - Page 1
Forum section: electronics / beginners

author: 60Hurts
author_rank: Contributor
timestamp: February 26, 2022, 09:10:58 pm
content: I had a Sony digital voice recorder that I wasn't using but was working fine. I pulled the batteries so they wouldn't corrode and threw it in my electronic junk box a couple of years ago. Today I was digging around and found it so I put some batteries in it and it was completely DOA, nothing on the LCD and no LEDs etc. even though it worked fine when I put it away. I took it apart to see if there was any corrosion or a broken wire, etc but nothing obvious that would explain its demise. So my question is what could have caused this? I know nobody can really say without digging in and seeing what failed but I was a little surprised that an electronic device could die just sitting in a box. Are there certain components that will die like this? Do you think it could have been avoided if I had kept live batteries in it? Thanks.

author: m k
author_rank: Super Contributor
timestamp: March 01, 2022, 04:41:02 pm
content: Many things can happen but power switch is first in line.Leaving batteries in is never a good thing but still some multimeters have same battery for quite some time.Can you put up any pictures?

author: 60Hurts
author_rank: Contributor
timestamp: March 02, 2022, 03:02:19 am
content: Quote from: m k on March 01, 2022, 04:41:02 pmAttached are some pics. I was just curious about what type of component could fail just sitting in a junk box without batteries. Usually battery corrosion will kill such devices. There was no power switch just a hold switch and operating switches (vol, rec, erase, A/B folder, etc). I recall that with batteries installed just pushing any button would bring up the LCD screen with info on stored voice memos and etc. I think the screen had auto off. It did have a DC power port to run it off an AC adapter (red connector) and I thought maybe the cutover switch was jammed thus blocking the battery power. I was able to measure 3V (2x1.5v) at that jack and on various traces and solder points on the board. I didn't have an AC adapter but I plugged in a headphone jack in the power port to see if it would unjam the cutover switch. No luck.

author: m k
author_rank: Super Contributor
timestamp: March 03, 2022, 10:58:42 am
content: Pictures are always good, people can imaginate.Still quite a bit of supporting components."Press any key" style is like a screen saver.Maybe it's now in deep sleep.Google says that hold button has some kind of a power function.2 seconds were also mentioned.

author: 60Hurts
author_rank: Contributor
timestamp: March 03, 2022, 04:30:39 pm
content: Quote from: m k on March 03, 2022, 10:58:42 amThe hold button is on the side of the case and is a two position switch not a push button. When I had it out of the case I flicked it (and other switches) back and forth to see if maybe it was bad but still got nothing. Could be a bad switch and trapped in sleep mode. I'll see if I can jump it to get anything going. Thanks!
Dead time of 4028 BCD with relais as source selector - Page 1
Forum section: electronics / beginners

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 22, 2016, 11:30:41 pm
content: Hello!I am thinking about a circuit... lets pretend that...I have 5 different power supplys and i would like to select just one that is routed to the output, to select a desired voltage and that i would be using relais for that.I could just use the µC that controls everything to select one relay to switch the input through to the output while keeping the other relais of.But i thought it would be nice to have one additional "fail safe level" and so i thought about using a 4028 binary to decimal decoder to ensure that only one input is selected at a time. So the supply rails to not get shorted against each other.When i would be using only the µC to control this i have control over the "swith over time / dead time" or what you would call it.The time before one relais engages and the other one disengages.When i would be using a 4028 i do not have that control, that would be a problem, right? I thought about puting a resistor and capacitor in with each logic output, so i get a delayed turn on.Would that be a viable solution?Greetings,Peter

author: danadak
author_rank: Super Contributor
timestamp: April 23, 2016, 12:51:23 am
content: Several options -1) uC control a DAC and a follow on power regulator to develop powerwith several different voltages you program the DAC. This wouldonly require one power supply.2) Use a diode on output of each supply, that way only the higher V supplyof any 2 supplies would be supplying load, until one is turned off. Power supplysense input would still go to load, so diode drop is effectively eliminated bycontrol circuit in active power supply.3) Use a dual uC, each checking each other to be in synch. Used in high relmedical injection pumps and similar high reliability requirements.Regards, Dana.

author: Paul Moir
author_rank: Frequent Contributor
timestamp: April 24, 2016, 12:28:33 am
content: A common industrial problem is where you have a motor you wish to reverse the direction of under the control of a PLC, where the two contactors (relays) must not be active at the same time. For those it's usual to see a mechanical interlock between the contactors, sometimes coupled with an electric one which operates off another set of contacts in the contactor.But for 5 relays, I think the easiest solution would be to limit the current going to the coils' driver such that this power rail is incapable of powering more than one coil at a time. It could be as simple as a resistor or if that's too wasteful then an active current limiter.While your idea could work, the charge-up of the capacitor will be only so much faster than the discharge time through the same resistor. This will get even worse if there's much hysteresis in the relay's pull-in / let go current. And of course there will be as anyone who's played with magnets knows.
Dead transistor breakdown voltage tester -- my fault? - Page 1
Forum section: electronics / beginners

author: jewelie
author_rank: Regular Contributor
timestamp: May 31, 2025, 02:40:31 am
content: I got one of these budget breakdown voltage testers a few days ago.I first checked the calibration, which was spot on.Yesterday I tested out various used/spare transistors against datasheets.Today I got tempted by curiosity to do something naughty......I rigged up a ~0.5mm spark gap between two sharp points.Keeping the current at the minimum of 50uA, at about 2000V it sparked, as expected -- as soon as I saw the spark and heard the sound I released the button to stop it.Now the device is permanent 0V on open circuit.I've checked, and the output really is dead Jim.I would have thought that this device should have coped with exactly this scenario?Was this a stupid thing to do? Is it my fault it's dead?If so, why would this have caused its demise?

author: MathWizard
author_rank: Super Contributor
timestamp: May 31, 2025, 03:50:13 am
content: OK I hope you take it apart and post some pictures, I'll have to look up some schematic, and some day either make 1 or buy a cheap one.

author: jewelie
author_rank: Regular Contributor
timestamp: May 31, 2025, 04:56:59 am
content: Doesn't oscillate.Transformer good.No voltage after transformer (not checked before it.)Diodes good.Capacitors not shorted.Transistors good diode test, not shorted.Resistors good.R41 I think should be 20ohms? Is that right? 18.4Mohms across R41. Open circuit?

author: jewelie
author_rank: Regular Contributor
timestamp: May 31, 2025, 08:44:34 pm
content: It was R41. Open circuit.Needs MELF 0207 20R 1% to fix properly.I don't have any 20ohm 1%, only though hole 1/4W 10ohm 1%, so I've used two of those in series.Not much space due to internal voltmeter.Not my proudest bodge but touch wood it works, for now.
Dealing with export controls - Page 1
Forum section: electronics / beginners

author: gmichael225
author_rank: Contributor
timestamp: December 21, 2017, 10:25:52 pm
content: Anybody else had issues with export controls from the US?(I'm based in Australia.)Digikey will no longer sell to me because I've said I'm manufacturing prototype products but I can't provide them evidence of manufacturing sales (that haven't happened yet) or details of an end user (from sales that haven't happened yet).I've also found certain products to be completely export-restricted: for example the NXP i.MX 6 SoloLite (via Mouser), and Digikey-brand chip resistors. I can't think why / under what classification these would be restricted (especially when the i.MX6 Dual and Quad processors are fine to be exported).What's even more annoying is there seems to be no way of checking whether an item will be able to exported when placing the order - I have to wait for an email days later stating that the order has been held.Normally I deal with a local distributor e.g. RS or Element14, but their range is somewhat limited.Anyone have any advice / strategies?

author: Bud
author_rank: Super Contributor
timestamp: December 21, 2017, 11:16:49 pm
content: No Digikey in AU?

author: Teledog
author_rank: Regular Contributor
timestamp: December 22, 2017, 12:05:07 am
content: Well, since you seem to be "a hobbyist", I'd just open another account, whether it be another name &/or address,.. & don't ever say you're in manufacturing.They were antagonizing me for business taxation info..I just use a BS business name, for the sole reason that couriers deliver faster to businesses than residential.Maybe try Digikey.ca? (and you are a "hobbyist", remember?) ;-)

author: nicalitz
author_rank: Regular Contributor
timestamp: December 22, 2017, 02:22:28 pm
content: There are other options, but none as convenient as Digikey or Mouser. You could try TTI?Not to encourage dishonesty, but when it comes to declaring the application and end-user, tell them what they want to hear. If you imply that you plan on selling a product, but you're not declaring the end user, it is much more difficult for them to approve.US export laws and regulations are unnecessary convoluted. I'm sure the distributors don't particularly like them either. You'll just have to learn to work with the system.
Dealing with IR2108 MOSFET/IGBT Driver - Page 1
Forum section: electronics / beginners

author: hussamaldean
author_rank: Unknown
timestamp: May 25, 2018, 08:56:43 am
content: Hi allrecently I bought this MOSFET driver which I will use to build an inverter (single and three phase).However, when I tried to use on of them to control the 2 mosfets I have for single phase inverter, I can see only the positive wave not the negative (i.e half-wave rectifier) based on the circuit belowcapacitor 10uF 400Vresistors 100Ohmdiode 0.5V forward voltage dropany solution or one mosfet driver drives only 1 mosfet ?regards

author: Seekonk
author_rank: Super Contributor
timestamp: May 25, 2018, 01:10:59 pm
content: I know that circuit is right off the data sheet, IT IS CRAP AND WILL NEVER WORK. It is a test schematic for testing each output SEPARATELY. Tie the two outputs together!

author: hussamaldean
author_rank: Unknown
timestamp: May 25, 2018, 02:21:10 pm
content: Quote from: Seekonk on May 25, 2018, 01:10:59 pmany suggestions?

author: jdraughn
author_rank: Regular Contributor
timestamp: May 25, 2018, 02:46:04 pm
content: Each of those drivers will drive two mosfets, but the output on the schematic can be misleading because it looks like two outputs for connecting each side of a load when they should be tied together. The top mosfet is responsible for passing the input voltage out, and the bottom one is responsible for passing the voltage coming in from the right, down to ground. You need two sets of the above circuit (which is a half bridge), one for each side of the load to create a full h-bridge.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 26, 2018, 07:19:23 pm
content: If you want more sensible feedback, then post the complete schematic of what you have tried, and tell us what kind of signals you have measured, and what you want etc.A cut & paste of an incomplete picture from a datasheet does not tell us much.

author: hussamaldean
author_rank: Unknown
timestamp: May 26, 2018, 07:24:34 pm
content: Quote from: Doctorandus_P on May 26, 2018, 07:19:23 pmHiI used the same circuit from data sheet and I applied PWM signal on HIN & LIN where HIN is PWM for like 10ms and pulled LOW while LIN is HIGH then HIN is LOW and LIN is PWM for 10ms

author: Seekonk
author_rank: Super Contributor
timestamp: May 27, 2018, 06:40:18 am
content: I don't understand. Did you tie HIN and LIN together?

author: hussamaldean
author_rank: Unknown
timestamp: May 27, 2018, 06:41:29 am
content: Quote from: Seekonk on May 27, 2018, 06:40:18 amnoeach one is connected to different pin of arduino

author: Seekonk
author_rank: Super Contributor
timestamp: May 28, 2018, 12:45:08 pm
content: I see no reason why you would use two pins on three phase.

author: james_s
author_rank: Super Contributor
timestamp: May 28, 2018, 10:33:57 pm
content: Keep in mind that LIN is inverted and HIN is not, so if you tie both together and drive with the same signal then the output will toggle between the two MOSFETs, which is what you want to happen.
Dealing with varying frequency pulsed load on a power supply - Page 1
Forum section: electronics / beginners

author: state_of_flux
author_rank: Contributor
timestamp: March 01, 2020, 07:15:49 pm
content: I have designed a resonant LCC converter that has two output voltages, -3KV @ 200mA and -6kV @ 10mA giving a total load power of 660W. It works fine under a constant load.The application is for a travelling wave tube, which is an RF amplifier. Depending on the mode of operation, the load can be pulsed/triggered on and off at various frequencies and duty cycles. For example, one scheme may be 100Hz pulse repetition frequency with 50% duty cycle at one extreme, and 1% duty cycle at a pulse repetition frequency of 100kHz at the other extreme. This is pulse widths of 5ms and 100ns respectively.This is where I am struggling to comprehend how to deal with this output pulsing. I have been recommended to use a MOSFET linear post regulator on the high voltage output to compensate for the output pulsing but cannot for the life of me find an example circuit on the web.The load pulsing causes transients from full load (>200mA) to substantially no load, (0A). As many will know resonant converters transient response is probably not fast enough to deal with this output pulsing while keeping the output voltage in regulation.Does anyone please have any advice on how this can be handled, and point me in the right direction to some documents for me to study. It would be greatly appreciated.Output voltage ripple allowed around the 6kV output is approximately 20Vpk-pk.
Debounce button for externally triggering DMM - Page 1
Forum section: electronics / beginners

author: radioFlash
author_rank: Regular Contributor
timestamp: March 18, 2015, 02:43:35 am
content: I'd like to to have a simple pushbutton to trigger my multimeter to take readings. I hooked up a scavenged snap action switch, wired it to the EXT trigger, and lo and behold, I get 2-3 readings per button press. So, it looks like I need to debounce it. Is the simplest/best strategy something like Fig 3 suggested athttp://www.ganssle.com/debouncing-pt2.htm?

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: March 18, 2015, 02:50:04 am
content: Yeah but now you need a power supply. Does the DMM have a pull up of some sort? You could just whack a capacitor across your switch to create a RC filter, and you might need a diode to clip negative-going signals.What DMM is this?

author: radioFlash
author_rank: Regular Contributor
timestamp: March 18, 2015, 11:24:45 am
content: It's a Keysight 34665a. The trigger is normally high at about 2.9 V and seems to have an impedance of 100k. I tried a 0.1 uF cap across the switch, and it's working nicely.Thanks for the suggestion!Edit:Added oscillocope screen shot of triggering using the switch with and without the capacitor.
debug vs release - Page 1
Forum section: electronics / beginners

author: A2
author_rank: Contributor
timestamp: July 15, 2014, 03:49:34 pm
content: I know the basic difference like debug has debug information & release have better opt settings.1. But in embedded, debug info always remains with host, only hex files gets burned to target MCU. So what difference it made.2. I have tried many different codes with debug or release. In both, code generated is always same. I never find it different.3. Is there any parameter/token/macro defined in compiler settings for deug?

author: Matje
author_rank: Regular Contributor
timestamp: July 15, 2014, 10:53:58 pm
content: Quote from: A2 on July 15, 2014, 03:49:34 pmFor 1.: Having debug info vs. not having it, but see 2. below.For 2.: You get to (meaning "have to" if you actually care about how stuff is build) define the compiler options for a debug/release build. If you define both to use the same options there will be no difference. Your IDE may not use different code generation options by default, for it has no magic knowledge about your requirements/intentions. Easy enough, no?For 3.: Probably yes, the documentation should describe it. A standard define (as in mentioned by the ANSI C standard) would be "NDEBUG" (meaning No Debug) for release builds.

author: mazurov
author_rank: Frequent Contributor
timestamp: July 16, 2014, 01:01:15 am
content: When you select debug build a DEBUG symbol gets defined (by default, you can find it in the IDE config and change it if you'd like). What happens after that depends on a particular project - for example, some files may or may not be generated or you may want to do conditional compiling depending on DEBUG being defined or not.

author: AlfBaz
author_rank: Super Contributor
timestamp: July 16, 2014, 03:31:02 am
content: It also depends on the target platform and your IDE. Some targets employ built in debugging hardware which can consume target resources. I've also seen people who's code works in debug mode but not in release due to this.As has been mentioned, debug mode also prevents some optimisations which can make it very difficult to debug if they're enabled. This can also be a source for headaches, for example software delays using "for" or "while" loops that get optimised away

author: miguelvp
author_rank: Super Contributor
timestamp: July 16, 2014, 03:33:32 am
content: Quote from: AlfBaz on July 16, 2014, 03:31:02 amAnd don't forget that some compilers will zero out uninitialized variables while release will have undetermined values. So your program could run fine under debug but not under release.
Debugging EV(BMW C-EVOLUTION K17) bike wiring - Page 1
Forum section: electronics / beginners

author: lordjohn
author_rank: Newbie
timestamp: May 03, 2025, 01:36:31 pm
content: i have a BMW C-EVOLUTION K17 2013, I let it still for 6months.now it's not working.Its imported and no one has any idea about it.can anyone guide me to find the problem as my own.problems:NOTHING IS WORKING.Display did'nt ON.please anyone guide me how to CHECK 3phase synchronous permanent magnet motor.HOW TO CHECK IF ALL WIRING IS OKAY?WHERE TO START?

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: May 04, 2025, 01:18:56 am
content: My first thought would be a bad/discharged battery.Jeff

author: themadhippy
author_rank: Super Contributor
timestamp: May 04, 2025, 02:18:47 am
content: do you intend filling the entire forum asking for the same thing?

author: ME
author_rank: Frequent Contributor
timestamp: May 04, 2025, 02:26:12 am
content: battery battery and did i mention battery?.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: May 04, 2025, 06:40:10 am
content: Here is the schematics
Debugging I2C with Tektronix TLA - Page 1
Forum section: electronics / beginners

author: newtekuser
author_rank: Frequent Contributor
timestamp: July 17, 2023, 12:58:06 am
content: Hello all - here's my debug setup:TLA5202 analyzer loaded with i2c support package.Probe assembly A2 pin 0 and C2 pin 0 hooked up to CLK and SDL lines of a DS3231 rtc chip. Ground pins are connected to ground of my target device.When I select the pins I get the error in the attached screenshot.The support package for i2c is not native to this scope and I took it from a TLA700 series:https://www.eevblog.com/forum/testgear/logic-analyzer-tla5202-vs-usb-analyzers-(probe-density-features-speed)/

author: m k
author_rank: Super Contributor
timestamp: July 20, 2023, 04:52:29 pm
content: So one is 3 and other is 4 but should be 2.Not very clock-alike.

author: RomDump
author_rank: Regular Contributor
timestamp: November 26, 2023, 10:45:32 pm
content: Quote from: newtekuser on July 17, 2023, 12:58:06 amI hope you already figured this out. You are not supposed to select Channel 0 on A3 or C3. The inputs are already selected.CK0() is SDL and CK3() is SCL. Remove the other selections. There is a word document that explains how to setup the logic analyzer in the zip package.
Debugging LTC3612 Step-Down DC/DC Converter - Page 1
Forum section: electronics / beginners

author: supperman
author_rank: Regular Contributor
timestamp: January 31, 2020, 12:06:02 am
content: I'm not sure what I'm doing wrong. I suspect it may be related to the conductor I chose..I have 3 similar circuits (see picture) that cascade when turned on to produce 3.3v, 2.5v and 1.2v to power an FPGA.The 3.3v fires up ok.. and seems stable. Some noise.The 3.3v PGood goes high and starts the 2.5V unit. (3.3v PGood is good.. never goes low after startup)2.5V fires up.. and 2.5V Pgood goes high.. but then glitches low from time to time. unstable. (even at zero load)2.5V out seems ok.. but does not hold up under load.when I force 2.5v PGood high.. then 1.2V fires up. It has a stable PGood like the 3.3v1.2v also can take a load.. but seems noisy when under load.This is being tested on a PCB and each board seems to have the same issue - so it is not just a one off fault.The fact that the 2.5v is the biggest problem in 3 similar designs.. it is very confusing to me.Data Sheet of TLC3612:https://www.tme.com/Document/5d0c950d94ad7f073004a3fa8721e621/3612fa.pdfData Sheet of Inductor:https://www.mouser.com/datasheet/2/427/sc15ah01-105489.pdf
Debugging RF devices - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: July 25, 2019, 04:56:03 pm
content: In past i worked on some wired communication protocols like ISP, I2C and UART and I found oscilloscope very useful to debug the communication.Now I am going to work on some RF based wireless modules like NRF-24, CC1101 and LORA (and some other RF modules)before getting started i want to ensure i have enough tools to debug the application, while learning around i understand that professional tools are very expensive.I wish to know some tools made for hobbyist that can help me to know if RF signal was transmitted on required frequency, it would be even great if we can know what data was transmitted just like we do on oscilloscope.Please suggest me what else may help in this scenario. I can spend $500 to $1000 for this.thanks,

author: MasterT
author_rank: Frequent Contributor
timestamp: July 25, 2019, 10:01:09 pm
content: https://www.amazon.ca/digital-Stick-RTL-SDR-Receiver-RTL2832U/dp/B00CM3LNMM/ref=sr_1_2Helps roughly estimate power, channel, activity in the time over waterfall diagram.
Decade resistor box - Page 1
Forum section: electronics / beginners

author: int2str
author_rank: Regular Contributor
timestamp: December 28, 2015, 07:26:33 pm
content: Decided to make a decade resistor box as a project with my son.Taught him how to create schematics and make a PCB layoutPictures here:https://goo.gl/photos/zK4c2vsn2PfqxYXT6Turned out well in the end (still need to put labels on the box).Lessons learned:- I ordered the components based on their electrical specs, not taking into account physical size, which caused the PCB layout to be more difficult then it should have been.- Consider the whole system specifications when considering each part (hint, there is one component which is under-spec'ed; guess which one?)And yes, this box was expensive. These can be had much cheaper on eBay. But the goal here was for my son to learn and end-to-end product cycle and for us to get a decade resistor with high quality, known-good components.Overall, very happy with the result!

author: zapta
author_rank: Super Contributor
timestamp: December 28, 2015, 07:35:34 pm
content: Looks very nice. It will serve you for long time.What kind of resistance transients do you get during changes? E.g. if you change from 8 to 9, can it get to 1 or infinity?This topology with a make before break switch may give smoother transitionshttp://gerrysweeney.com/wp-content/uploads/wppa/144.png

author: int2str
author_rank: Regular Contributor
timestamp: December 28, 2015, 08:22:06 pm
content: It shoots up towards infinity.

author: tggzzz
author_rank: Super Contributor
timestamp: December 28, 2015, 10:30:55 pm
content: Quote from: int2str on December 28, 2015, 07:26:33 pmIf your son was involved in all those aspects, saw your thought processes, and how 20:20 hindsight is A Good Thing, then the box was superb value for money.But you know that

author: Dave
author_rank: Super Contributor
timestamp: December 29, 2015, 02:57:49 pm
content: It would be a good idea to stagger those switches, so you have space around them for a dial on the front panel.
Decade voltage dividers in digital test equipment? - Page 1
Forum section: electronics / beginners

author: altaic
author_rank: Unknown
timestamp: March 17, 2016, 10:14:21 pm
content: It seems odd to me that decade voltage dividers are used in digital test equipment-- digital test equipment use ADCs which produce binary, and engineers already have to compute noise based on bits. Plus, multiplying/dividing the result of the ADC by a power of 2 is just a bit-shift operation, which is really simple and low-power. Furthermore, dividing voltage by two with resistors is really easy: just match the resistors, which is easy to high-precision with something like a Wheatstone bridge.Is there a technical reason behind not using powers of 2, like noise distribution? One would think we'd use some sort of prime series in that case, and omit any multiple of two.Are precision binary voltage divider networks available? I haven't been able to find even non-precision binary voltage divider networks.

author: Vgkid
author_rank: Super Contributor
timestamp: March 17, 2016, 10:22:31 pm
content: Never seen any binary voltage dividers, though you could look through the various resistor networks that are availlable.You can always order some custom ones...

author: danadak
author_rank: Super Contributor
timestamp: March 17, 2016, 10:44:53 pm
content: R-2R ladders used extensively in DACs, and early SARs.https://www.google.com/imgres?imgurl=http%3A%2F%2Fwww.dnp.fmph.uniba.sk%2F~kollar%2Fje_w%2Fimage497.gif&imgrefurl=http%3A%2F%2Fwww.dnp.fmph.uniba.sk%2F~kollar%2Fje_w%2Fel3.htm&docid=dGxyx3UXocLTfM&tbnid=8w3EHrowjsAC4M%3A&w=1168&h=616&ei=QTPrVs-6FMSy-AHh-afwBARegards, Dana.

author: altaic
author_rank: Unknown
timestamp: March 18, 2016, 12:01:29 am
content: Quote from: danadak on March 17, 2016, 10:44:53 pmAh, thanks. For some reason I only associated resistor ladders with DACs, but of course they are used for Flash ADCs (and, I take it, early SAR ADCs).
decap and bulk cap discharge path - Page 1
Forum section: electronics / beginners

author: Vcky_electro
author_rank: Contributor
timestamp: January 03, 2020, 08:21:13 am
content: Hi,I have one doubt. Can anyone answer for that,We are using decabs and bulk caps in our IC's. After power cable is unplugged, How does the capacitors are discharge?Thanks,Vicky.

author: mikerj
author_rank: Super Contributor
timestamp: January 03, 2020, 01:08:42 pm
content: Through any components that draw power from the rails the caps are connected to.

author: Vcky_electro
author_rank: Contributor
timestamp: January 03, 2020, 02:56:05 pm
content: If it is CMOS IC then how the charge in the decap discharges?

author: mikerj
author_rank: Super Contributor
timestamp: January 03, 2020, 05:40:47 pm
content: What do you mean by "decap"? If it's a decoupling capacitor across the supply rails then it makes no difference if an IC is CMOS or bipolar, anything that draws current from the supply rails will discharge the capacitors.If you mean something else by "decap" you will have to explain or preferably give an example circuit.
Decent second hand scope and what to be aware of - Page 1
Forum section: electronics / beginners

author: shobo
author_rank: Regular Contributor
timestamp: November 21, 2017, 08:10:29 am
content: i found a TDS460A on a ebay-like site in Romania and the guy is asking about 500 bucks on it.it is worth buying or should i buy a ds1054z instead?if it's worth buying,what are the things to be aware and to check before purchase?

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: November 21, 2017, 08:51:09 am
content: The exact same question was asked a few days agoTake a look!https://www.eevblog.com/forum/beginners/oscilloscope-advice-ds1054z-vs-tektronix-tda460a/

author: bd139
author_rank: Super Contributor
timestamp: November 21, 2017, 09:22:58 am
content: I'd go for the DS1054Z. If that Tek goes bang, which they do regularly, then it's going to be a write off or a difficult job replacing parts. I think I'd only touch an old analogue scope or a brand new digital one these days. That grey area of digital scopes in the middle is a bit scary.

author: tggzzz
author_rank: Super Contributor
timestamp: November 21, 2017, 09:28:31 am
content: Quote from: bd139 on November 21, 2017, 09:22:58 amYes.Plus it is only recently that small/cheap DSOs have become as usable in a general purpose context as old analogue scopes. For a couple of decades DSOs were only king where the applicationrequiredstorage.
Deceptive AC Adapter? - Page 1
Forum section: electronics / beginners

author: Perplexed
author_rank: Newbie
timestamp: February 17, 2015, 05:05:34 pm
content: Hello, I have an AC Adapter plug that is Gospel brand with the Model # GP006AU that needs to be replaced. I went on Amazon and found a listingclaiming to be selling a compatible AC Charger:http://www.amazon.com/gp/product/B00SY22F9U/ref=oss_productIt specifically states the model number but what they sent me is something with a model # FU05-9050100-A1. The input and output voltages are the same but the actual output plug end is different from the Gospel Brand GP006AU, and therefore useless. I figured with the exact brand name # in its feature listing I would have avoided this issue. Am I in the right to complain about this or should I have to buy some sort of output plug adapter?Thanks for the help.

author: Whales
author_rank: Super Contributor
timestamp: February 18, 2015, 12:16:02 am
content: If it does not have the part number as you ordered you are right to complain. It may also vary in other ways (eg can't deliver as much current without failing).If you still have the old power supply you can cut off it's output jack and wire that on if you're up to it. Otherwise dispute it with the seller.

author: rdl
author_rank: Super Contributor
timestamp: February 18, 2015, 01:53:49 am
content: Dispute it. Even if the voltages and current capacity are equal, if the plug doesn't fit it's not compatible is it? Hacking the wires to install the correct plug isn't something you should have to do, and may void whatever warranty it may have come with.

author: Perplexed
author_rank: Newbie
timestamp: April 08, 2015, 03:06:56 am
content: I disputed it, and got my money back. Thanks guys!
Deciding cut off frequency for low/high pass filter - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: October 24, 2019, 12:03:22 pm
content: 1. I have a application in which need to get 10Hz-240Hz signal. So first made a 240hz LFP & then connected 10Hz HPF after that. Ckt is attached. Res/cap values are taken from TI workbench, nearest available will add later.2. I was reading that when designing a filter, at fc gain is at 3db lower.3. I need to measure 10Hz to 240Hz, so at my 10Hz signal with 3db lower & similarly 240Hz signal will be 3db lower.4. So what is I want no gain loss at 10Hz or 240Hz. How much lower frequency should I select than 10Hz, so that at 10hz there is no loss.Similarly for 240Hz, how much higher frequency should i select so that there is no signal loss at 240Hz.5. is there any general rull of thumb for this?6. Similarly for sample signal at 240Hz with MCU adc, what is frequency for adc sampling to be selected. Generally I have select 10 times atleast. But is there any general rule of thumb for this also.

author: pwlps
author_rank: Frequent Contributor
timestamp: October 24, 2019, 01:23:17 pm
content: I don't know if there is a rule but there are online Sallen-Key filter calculators able to output the Bode plot e.g.http://sim.okawa-denshi.jp/en/OPseikiLowkeisan.htmso you can adjust your values for the shape you want.

author: StillTrying
author_rank: Super Contributor
timestamp: October 24, 2019, 01:26:08 pm
content: As drawn that circuit needs + and - supplies.I don't know any more about the analogue filters than you do.https://www.electronics-tutorials.ws/filter/second-order-filters.html

author: Audioguru again
author_rank: Regular Contributor
timestamp: October 24, 2019, 05:54:44 pm
content: The second-order filters produce a simple 12dB per octave slope. But near the cutoff frequency there is a more gradual change.Simply simulate the circuit to see how much extra frequency you need for the amount of level loss you can tolerate.Most Sallen-Key second order Butterworth filters with a gain of 1 use same value parts except the feedback part is half/double the other part.You said you want no loss at 10Hz and 240Hz then the bandpass will be enormous. I simulated it with a small amount of loss here:EDIT: This simulation has an error with R2. The sim is corrected in my next post.

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: October 28, 2019, 04:58:18 am
content: thanks for input 5-400hz gives desired results in my case

author: Audioguru again
author_rank: Regular Contributor
timestamp: October 28, 2019, 01:07:17 pm
content: Sorry, my simulation had an error (R2), here is the correct simulation:
Decoding Capacitor Marking? - Page 1
Forum section: electronics / beginners

author: meeshu
author_rank: Newbie
timestamp: March 02, 2019, 04:05:11 am
content: I'm trying to understand the marking on a small blue ceramic capacitor with three lines of marking.First line has - BNSecond line has - 101KThird line has - 1kVLFrom web searches and general understanding of components -> the BN means the capacitor dielectric and/or the temperature coefficient of capacitance change with temperature.> The 101K means a capacitance value of 100pF with capacitance tolerance K (± 10%, I believe).> the 1kVL means a rated voltage of 1000 volts (1kV), but the capital "L" at the end is a mystery!?So what does the "L" at the end of the third line mean, please?And, if possible, can any manufacturers who make this capacitor be identified also, please?Thank you.PS I can't seem to attach images of the capacitor!?

author: RES
author_rank: Regular Contributor
timestamp: March 02, 2019, 02:43:08 pm
content: https://www.wikihow.com/Read-a-Capacitor

author: meeshu
author_rank: Newbie
timestamp: March 03, 2019, 01:00:04 am
content: Thanks.But that reference doesn't seem to explain the meaning of any letters after the voltage rating(?)Most ceramic capacitors I've seen only have the voltage rating marked (such as 1kV) without any following letters. So I suspect the "L" marking after the voltage rating on this capacitor may be specific to only one or a few manufacturers?Regardless, I would still like to know the meaning of the letter "L" marking.

author: Jwillis
author_rank: Super Contributor
timestamp: March 03, 2019, 01:52:04 am
content: The only thing that makes sense is a tolerance code.http://my.execpc.com/~endlr/markings.html

author: meeshu
author_rank: Newbie
timestamp: March 03, 2019, 04:57:59 am
content: Thanks.But there is a capacitance tolerance code (K) already marked. And as far as I'm aware there aren't voltage tolerance codes (for ceramic caps)?If that "L" is actually the voltage tolerance code, that is very unusual!!Anyway, it would be good to get verification of this by finding a ceramic capacitor manufacturer who actually states clearly the function/meaning of the letters after the voltage rating marking.