hybridfree/eevblog-posts huggingface dataset:
Throttle position sensor and ECU - Page 1
Forum section: electronics / beginners

author: scarr999
author_rank: Contributor
timestamp: March 02, 2022, 05:52:29 pm
content: Hi All,I am trying to make a remote that can rev my engine. I tested the principle by finding the ECU inputs from the throttle position sensor and just injecting (adding) a voltage to it. The engine revved OK.I then made an arduino with I2C DAC, when I connect the output of the DAC to the ECU input and try to rev the engine usng the vehicles manual throttle it does not respond! I disconnect the arduino and it works again. I assume the DAC is holding the input low preventing the normal throttle working, I'm looking for advice if adding an open collector transistor to the DAC output would work?voltages are low 0-1.3v DCThanksSteve

author: ifrythings
author_rank: Contributor
timestamp: March 03, 2022, 02:03:29 am
content: I’m not sure what DAC your using but there mite be a power down mode in the DAC that will disconnect the output amplifier from the pin, this would allow the throttle pedal to work again. On a mcp4725 DAC, page 20 explains how this works.

author: Renate
author_rank: Super Contributor
timestamp: March 03, 2022, 11:05:18 am
content: You're connecting two outputs together and they're fighting. Ok, you might be able to use an output enable on your DAC, but the TPS is enabled all the time. Depending on how it's made, the idle position may almost be a short to ground.One way would be with an analog multiplexor, but are you sure that you want to do this? Cruising in the fast lane and the engine cuts out completely? In downtown traffic and the throttle red lines?

author: SmallCog
author_rank: Frequent Contributor
timestamp: March 03, 2022, 10:09:50 pm
content: I'm surprised its as simple as injecting voltage - When I looked into making an idle-up for my car it had some fancy hall effect encoder arrangement so you're lucky!You haven't said what the purpose is, but given you said remote I'm assuming its not for use whilst you're driving?In that case if you've got the Arduino working without the pedal, and the pedal obviously works without the Arduino, then have the Arduino disconnect the pedal when it's putting the revs up and disconnect itself when it's not.Whatever you do be bloody careful, I've had the displeasure of driving a vehicle with the throttle jammed open.

author: langwadt
author_rank: Super Contributor
timestamp: March 03, 2022, 10:19:23 pm
content: add a diode in series with the dac output (you'll need to increase the DAC output by ~0.7V). Then manual throttle will work normally, DAC voltage can only add to that
Through Hole to SMD components - Page 1
Forum section: electronics / beginners

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 04, 2017, 07:51:03 pm
content: Hi All,i am searching for a few SMD components and cannot seem to find the 0.1uf 400v (https://www.digikey.com/product-detail/en/nichicon/QXK2G104KTPTZH/493-3574-ND/2118520) in an SMD form. Are these in through hole size only ?

author: Zero999
author_rank: Super Contributor
timestamp: August 04, 2017, 09:02:15 pm
content: Quote from: anishkgt on August 04, 2017, 07:51:03 pmThrough hole is more common for higher voltage components because the creapage distances are normally greater.Here's an alternative in SMT format, but the AC voltage rating is only 160V, even though the DC rating is the same at 400V.https://www.digikey.com/products/en?keywords=LDEME3100KA5N00Here's one rated to 200VAC but RS don't have any in stock and Digikey don't stock them at all.http://uk.rs-online.com/web/p/pen-film-capacitors/8752399/

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 04, 2017, 09:15:45 pm
content: Thanks i will just stick to the through hole for this component.
THS1030 ADC worth trying? - Page 1
Forum section: electronics / beginners

author: Stonent
author_rank: Super Contributor
timestamp: October 19, 2013, 09:56:07 am
content: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_288681_-1http://www.ti.com/lit/ds/slas243e/slas243e.pdfJameco has these TI THS1030 10bit 30Msamples/sec ADCs on clearance for $2.25 each. I'm intrigued by them but wonder if trying to implement one is doable at the hobby level.So in theory this thing could be dumping data at me 30 million times a second. What would you need in order to capture data like that?I see that it has 10 output pins so I gather that a sample will be a 10 bit binary number represented by those pins at a state of highs and lows.If it's as simple as connecting those 10 pins to 10 GPIO pins on another device that can react at the speed you feed data to it, I might consider it but if it's one of those, "yeah the ADC is $3 but you need another $50 worth of components before you can connect to it" things I'll just not bother.(Other device meaning, a microcontroller, Raspberry Pi, Beaglebone, parallel to serial shift register etc)

author: amyk
author_rank: Super Contributor
timestamp: October 19, 2013, 10:37:11 am
content: What do you want to make with it?

author: Rerouter
author_rank: Super Contributor
timestamp: October 19, 2013, 10:55:26 am
content: it is made to be read in parallel to utilize the full update rate, you would need your shift register running at 300Mhz to run that into a serial interface and that starts edging into RF black magic territory,as far as how the chip goes, the offset and gain specs are horribly, 3.5% of full scale range gain error means your 3V just became 2.9 - 3.1V for a 3V supply,

author: Marco
author_rank: Super Contributor
timestamp: October 19, 2013, 02:03:03 pm
content: As long as the offset and gain errors are stable you can calibrate them out.Generally people use FPGAs to interface with fast ADCs, to have any success with microcontrollers or processors at these speeds they would have to support triggered DMA for the GPIO ports ... no idea which boards can do that.
THS8135 usage - Page 1
Forum section: electronics / beginners

author: VEGETA
author_rank: Super Contributor
timestamp: July 09, 2023, 07:43:01 am
content: Hello,I have ADV7181D which converts analog video to digital, and the chosen output format is 20-bit YCbCr 422.I plant to hook THS8135 after it to convert it to analog YPbPr, however I am confused from sync insertion stuff.for YPbPr output, I think I should have these controls:sync and sync_5 -> 0 for "Video DAC mode. Negative sync inserted".M1 = 1 and M2 = 0 -> for YCbCr 422 2x10b. Here M1 is latched as "M1_INT" since sync input control pin is 0.so my question, where does sync signal comes from?I know in 2x10b ycbrc sync code is embedded but the same controls can be used for rgb 444 and ycbcr 444 digital inputs which do not have sync signal.my guess is that in order for sync to be inserted properly, I should have a composite sync signal on the "sync" control pin, this Csync signal can be taken from LMH1980 IC... this is when I need THS8135 to insert the sync on Y or G pin but if I don't want that then I should choose "sync" and "sync_t" to be 1 all the time.is my understanding correct?

author: liaifat85
author_rank: Regular Contributor
timestamp: July 11, 2023, 07:28:23 am
content: If you choose to use a composite sync signal, you can obtain it from an IC like the LMH1980. The LMH1980 can extract the composite sync signal from the incoming video signal and provide it to the sync input of the THS8135.Alternatively, if you don't want to insert sync externally, you can keep the "sync" and "sync_t" controls set to 1 all the time. This configuration implies that the ADV7181D will generate the sync signals internally, which will be passed to the THS8135 without the need for external sync insertion.

author: VEGETA
author_rank: Super Contributor
timestamp: July 11, 2023, 09:06:43 am
content: Quote from: liaifat85 on July 11, 2023, 07:28:23 amhmm this is interesting.adv7181d output is ycbcr 422 2x10b which has sync signals embedded within it... do you mean it will be put on the output Y signals even if i didn't insert it externally?i say this because ths8135 have a mode where it takes ycbrc or rgb 444 parallel bits input which does not have sync embedded. what will happen if i didn't insert the sync there? for rgb it can be ok but ypbpr analog video must have sync on y.please inform me how did you know the ths8135 will output the embedded sync without me putting the external sync.EDIT:I found this in datasheet:Quotethus, it requires csync input on the sync pin since it cannot extract it from embedded codes.
THT vs SMD electrolytic cap body - Page 1
Forum section: electronics / beginners

author: kellogs
author_rank: Regular Contributor
timestamp: January 04, 2023, 02:15:42 pm
content: THT body, as we know, standard appearance:SMD body, standard appearance:Does anyone know why some THTs have a SMD-looking body ?Does the SMD standard appearance caps have a way to prevent explosion - do they bulge / break their tops open ?

author: jmelson
author_rank: Super Contributor
timestamp: January 04, 2023, 04:40:29 pm
content: Likely, now they are made on the same production lines. The SMD style are made like THT caps, then the leads are swaged flat, the foot is placed over the leads, the leads are then bent out and cut flush with the foot. I have had exactly ONE SMD cap blow its top off during reflow.Jon

author: wraper
author_rank: Unknown
timestamp: January 04, 2023, 05:13:40 pm
content: The only difference is that TH caps have a heatshrink on them. My guess is that TH caps are often packed tighter, often inserted not exactly straight and with uninsulated terminals of other components besides them. So heatshrink that provides insulation is a useful feature. SMD caps on other hand always stay straight due to plastic support and rarely have anything conductive besides them. TH electrolytic caps without a heatshrink also do exist, but it's not common. Way more common are TH polymer caps which are exactly the same as their SMD version except plastic support and flattened leads.

author: wraper
author_rank: Unknown
timestamp: January 04, 2023, 05:18:40 pm
content: QuoteSmall caps rarely have a vent, both SMD and TH. If they fail rapidly, aluminum can flies away like a missile. Larger caps usually have a vent for either type. Polymer caps do not have a vent.
Thurlby TSX3510P hiding in Tenma Case - Page 1
Forum section: electronics / beginners

author: watchmaker
author_rank: Unknown
timestamp: October 17, 2023, 03:23:26 pm
content: I need it like a hole in the head, but I was successful tooling up in the 1990s when watchmaking was dead. Then I bought $2000 B&L, AO and Nikon stereo scopes for $100 when the labs were switching to digital imaging.No More loupes!! I sold a number for a very small profit as a service to young watchmakers.It is a sickness; but I do see the same thing as happening now in electronic test equipment. Maybe related to the downplaying of understanding the fundamentals in favor of programming and connecting modules? If so, I can all but guarantee this will reverse in a few years.The one place I screwed up was I bought about 20 Nikon FMs for less the $20 @, carried them for 15 years, gave 2 to my daughter and gave away the rest.NOWsome SOB made a film canister sensor for the damned things!Anyway, this PSU (it is a series one though) was sitting on ebay, looked up the manual and it took me to the Thurlby manuals. Same thing.Already have an Instek GPS 4303 I bought for $100 and that boat anchor Lambda LK 351 that needs a caring home (please); but.....So, if you are looking, look beyond the badge. Download the manual to see what it really is.I am pretty pathetic, (2) 8840/AFs, one 3478A, one GDM 8284 (for quick Freq and high AC amps), Siglent SDS124XE, Agilent 2 channel digital and a BK 1520 2 channel analog scopes, Fluke 27/FM (US Army Calibrated to Nov 24), AND a Diligent Analog Discovery 2 which shrinks everything you need into 2 inch (5 CM for the Imperial challenged) square footprint.The most expensive thing I bought was the Discovery. If I paid $150 for anything else it was a lot. Look around and be patient. Stuff is out there. BTW, ALL meters agree down to the last 2 digits.One thing I never regretted was buying top-quality, correctly operated, used equipment.I mean, the Flukes were $1400 USD instruments just 20 years ago. The Thurlby is still an $1100 USD supply. Just like buying a Schaublin 102 for $500 or an USAF surplused Levin lathe w/ everything in the catalog for $5K in the 1990s. After the supply dries up, everyone wants you to die so they can get access to your stuff.And for the cash challenged, I cannot more highly recommend the Analog Discovery 2. It is a marvel.Regards,Dewey

author: coromonadalix
author_rank: Super Contributor
timestamp: October 17, 2023, 04:32:34 pm
content: and ?

author: watchmaker
author_rank: Unknown
timestamp: October 17, 2023, 06:08:10 pm
content: Quote from: coromonadalix on October 17, 2023, 04:32:34 pmOn to CKT analysis and Differential Calc. Getting a kid from the local HS to tutor me at the library.
Thyristor Trigger Module questions  - Page 1
Forum section: electronics / beginners

author: daniel444
author_rank: Regular Contributor
timestamp: April 02, 2020, 02:31:16 am
content: hiim looking at this Thyristor Trigger Module, AVR-25 by united automationthe datasheet seems to imply it can be used on the primary side of a transformer like a dimmer, i thought it was a no-no to put a dimmer before a transformer ?https://au.rs-online.com/web/p/thyristor-trigger-modules/1953494/

author: bob91343
author_rank: Super Contributor
timestamp: April 02, 2020, 03:09:18 am
content: It's unclear from the information, which does not indicate whether it's a full wave or half wave unit. You are right that if it's half wave, using a single SCR, it will have a dc component in its output. Full wave is better, as it controls both positive and negative so should be okay for transformers.Having said that, they may have some clever way of doing it that eliminates such concerns. I don't know.
TI 79M20C replacement - Page 1
Forum section: electronics / beginners

author: giosif
author_rank: Frequent Contributor
timestamp: December 10, 2016, 11:36:37 am
content: Hi,I am trying to find a replacement for a suspected bad -20V voltage regulator - the logo seems to be that of TI and the marking says 79M20C.I've searched over the net but, excepting AliExpress, I couldn't find anything similar.Anyone has any suggestions where I could find a replacement for this, TI or non-TI?Thanks!

author: Ian.M
author_rank: Super Contributor
timestamp: December 10, 2016, 12:02:59 pm
content: 79M20 regulators do seem to be somewhat rare. For 78/79xx series regulators M in the middle codes 500mA current rating (as opposed to L for 100mA, no letter for 1A and S for 2A) so unless you need the same current limit as the original, you can substitute a 7920 regulator in a compatible package. Otherwise use a 79M15 regulator + a 5.1V Zener in series with its GND leg, anode to the regulator.

author: giosif
author_rank: Frequent Contributor
timestamp: December 11, 2016, 08:03:02 pm
content: Thank you for the detailed response!Interesting suggestion with the -15V regulator + the 5.1 Zener.One question on it, though: wouldn't the Zener need to sustain a 500mA reverse current?

author: Ian.M
author_rank: Super Contributor
timestamp: December 11, 2016, 08:32:59 pm
content: No. it only has to handle the 79xx GND leg current which is typically between 1mA and 10mA over the whole load current range. Check your specific regulator manufacturer's datasheet to confirm the GND leg current will keep the Zener at an appropriate point in it's Ir/Vr characteristic.Another option would be a LM337, with the ADJ pin lifted so you can insert a potential divider between the output and ground to set it to -20V. The other two pins and the tag are compatible. However that has an even higher current limit: 1.5A

author: giosif
author_rank: Frequent Contributor
timestamp: December 11, 2016, 09:12:53 pm
content: Ah, ok. Would that be the inbut bias current figure for the voltage regulator?I am aware of the adjustable regulators, but I wanted to avoid that route, if possible.

author: giosif
author_rank: Frequent Contributor
timestamp: December 11, 2016, 10:22:44 pm
content: Quote from: blueskull on December 11, 2016, 10:19:04 pmReally don't know.This is for a dead meter (Solartron 7060).In any case, I went ahead and bought both a -15V voltage regulator + a few types of 5.1V Zener diodes, but also a 7920, in case the first combination proves a challenge.
ti an31 opamp guide component question - Page 1
Forum section: electronics / beginners

author: PH9Z
author_rank: Newbie
timestamp: November 01, 2018, 08:31:24 pm
content: I'm playing around with opamps trying to build the examples from AN31 guide:http://www.ti.com/lit/an/snla140b/snla140b.pdfMy question: what is q1 in figure 55, same as q1,q2 and q3?I don't regonize the part.....regards John

author: MasterT
author_rank: Frequent Contributor
timestamp: November 01, 2018, 09:29:41 pm
content: MOSFET.

author: Audioguru
author_rank: Super Contributor
timestamp: November 01, 2018, 09:56:59 pm
content: Ph9z, I see what is wrong.The LM102 opamp is obsolete and the 4 terminals Mosfet is also obsolete. Maybe in 1959 a Mosfet had 4 terminals.

author: capt bullshot
author_rank: Super Contributor
timestamp: November 01, 2018, 09:58:11 pm
content: Quote from: MasterT on November 01, 2018, 09:29:41 pmYes, but a nowadays quite uncommon variant with bulk bonded out. Bulk as opposite of gate, usually internally connected to source.

author: PH9Z
author_rank: Newbie
timestamp: November 02, 2018, 06:41:51 am
content: THX, I will start playing around with a BF511!Regards John

author: Zero999
author_rank: Super Contributor
timestamp: November 02, 2018, 02:35:21 pm
content: Quote from: PH9Z on November 02, 2018, 06:41:51 amThat's an N-channel JFET.What's the supply voltage?How about the CD4007 or an analogue switch, such as the CD4016?
TI BQ78350 confusing schematic - Page 1
Forum section: electronics / beginners

author: redgear
author_rank: Frequent Contributor
timestamp: July 24, 2019, 07:05:41 am
content: I am trying to reproduce the sample schematic from the for TI BQ78350, however the pin out of the IC is different in the schematic and pin diagram. I'm a bit confused.This is how it is in the schematicThis is how the pins are numberedThanksEdit: The IC on the right in the first image is the BQ78350

author: bitwelder
author_rank: Super Contributor
timestamp: July 24, 2019, 07:19:52 am
content: In the simplified schematic the pins seem to be sorted in functional order (i.e. conveniently to draw a readable schematic), not strictly according to the pinout.

author: redgear
author_rank: Frequent Contributor
timestamp: July 24, 2019, 08:03:26 am
content: Thanks, so if I am building this component on an EDA, I should follow the Pin Diagram (second image), correct?

author: bitwelder
author_rank: Super Contributor
timestamp: July 24, 2019, 09:13:03 pm
content: Yep!
Ti Buck converter IC Simulation usign LTspice - Page 1
Forum section: electronics / beginners

author: Sudarshana.S
author_rank: Newbie
timestamp: June 07, 2025, 01:05:05 pm
content: Hello, I'm working on a PCB design for one of my projects and decided to use the LM3150, a buck converter IC from Texas Instruments. I used their Webench Power Designer to run a few simulations. However, I also wanted to run the same simulations using LTspice. When I tried to simulate the circuit in LTspice using their provided PSpice model, I encountered an error message. For this, I used the exact same circuit schematic provided by Texas Instruments for simulation. I've attached a screenshot of the error message below. I’d like to know whether it's actually possible to simulate Texas Instruments ICs using LTspice. If it is possible, could someone help me understand what I might have done wrong in my simulation?

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: June 07, 2025, 06:36:12 pm
content: Please make sure that no node is left unconnected.https://electronics.stackexchange.com/questions/639286/ltspice-error-missing-node

author: Ian.M
author_rank: Super Contributor
timestamp: June 07, 2025, 07:17:34 pm
content: The T.I. PSPICE model above is encrypted, with only its interfaces in SPICE3 compatible form, so is unusable in LTspice. However T.I. also offer an unencrypted PSPICE model, whioch may well work, and if it doesn't (due to PSPICE specific syntax) should be fixable. Seehttps://www.ti.com/product/LM3150#design-tools-simulation(near the bottom).

author: Sudarshana.S
author_rank: Newbie
timestamp: June 08, 2025, 08:51:14 am
content: Oh, thanks for the help. Like you said, I just changed the spice model and now it works.

author: Sudarshana.S
author_rank: Newbie
timestamp: June 08, 2025, 09:00:05 am
content: Thank you very much for your help. I was able to correct my mistake just as you suggested. I also replaced the model I was using, as it turned out that it couldn't be simulated properly.
Ti CD4071B - floating output pins OK? - Page 1
Forum section: electronics / beginners

author: [Chrille]
author_rank: Contributor
timestamp: October 05, 2022, 07:05:07 pm
content: Hi,I want to use a Ti CD4071B (quad OR-gate) for a project of mine. Is it OK to have floating/not connected output pins? Right now I only use one of the four or gates available on the chip. I browsed the datasheet but I did not find anything written about floating output pins. It did however say that all input pins should be connected to VDD or VSS.So, what do you guys say? Is it OK to leave the unused outputs floating?

author: james_s
author_rank: Super Contributor
timestamp: October 05, 2022, 07:18:01 pm
content: Floating output pins are fine, it's floating input pins you want to avoid.

author: Zero999
author_rank: Super Contributor
timestamp: October 06, 2022, 08:35:49 pm
content: The outputs never float. They're internally either connected to VDDor VSS, via output transistors.
TI F28069M Launchpad and Simulink - Page 1
Forum section: electronics / beginners

author: kaadam
author_rank: Contributor
timestamp: September 30, 2015, 09:15:32 pm
content: Hello!I have built a 2*50kW three phase inverter for motor control pruposes, and i want to try more control algorythms wint Simulink, so i bought a TI LAUNCHXL-F28069M devboard, and wanted to bulid the official TI & Mathworks example:https://www.youtube.com/watch?v=ncM7N-hLKQM.Matlab ouptu shows this log:http://prntscr.com/8mbge2the missing .h file actually does not exist on my whole computer...I'm completely new at Embedded Coder in Simulink, so i don't even know where to start the troubleshooting, does anyone hane any expereience about Embedded Coder or have any idea about this topic?

author: rsjsouza
author_rank: Super Contributor
timestamp: October 01, 2015, 02:56:59 pm
content: The file <F2806x_Device.h> is part of the software packagecontrolSUITE, but I wonder if it should exist also in one of the include directories shown in your project.Looking at the screenshot my best guess would be under:C:\MATLAB\SupportPackages\R2015a\texasinstrumentsc2000\toolbox\target\supportpackages\tic2000\inc

author: kaadam
author_rank: Contributor
timestamp: October 01, 2015, 04:02:14 pm
content: Thanks!I was able to get it run. I had to add some environment variables manually. I don't know it's because Windows 10 or Matlab r2015, but it was not as easy as the demo video shows..
TI FTDI? - Page 1
Forum section: electronics / beginners

author: zerorisers
author_rank: Regular Contributor
timestamp: April 24, 2015, 01:48:37 pm
content: Hello, I was wondering if there was any kind of FTDI chip from Texas Instruments. I am planning on using my student samples to try making my own "launchpad" type device. I think This would be a great project to get into building something I will be proud of and can afford!

author: Howardlong
author_rank: Super Contributor
timestamp: April 24, 2015, 02:11:07 pm
content: Quote from: zerorisers on April 24, 2015, 01:48:37 pmFWIW, TI already use FTDI devices for onboard debuggers on many of their Launchpads.

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 24, 2015, 02:15:51 pm
content: Quote from: zerorisers on April 24, 2015, 01:48:37 pmDecent alternative to the FTDI FT232, can thoroughly recommend.Cypress is way, way better then FTDI:https://www.eevblog.com/forum/projects/cypress-cy7c65213-a-pin-compatible-ft232r-replacement/

author: oPossum
author_rank: Super Contributor
timestamp: April 24, 2015, 04:39:16 pm
content: TI has the TUSB3410. It has CDC ACM in ROM and can also load firmware from serial EEPROM or the host.http://www.ti.com/product/tusb3410

author: timb
author_rank: Super Contributor
timestamp: April 26, 2015, 04:26:00 am
content: The MSP430F5529 has USB onboard and can easily be programmed to act like a USB Serial controller with about 6 lines of code in Energia (the Arduino equivalent for MSP430/Tiva C/MSP432/CC3200 devices).Sent from my Tablet

author: zerorisers
author_rank: Regular Contributor
timestamp: April 28, 2015, 01:16:34 pm
content: Thank you all for the great reply's. I have recieved a MSP430FG4250IDL from TI and i think i may have abused the samples to the limit. Too much I want to play with pops into my head when browsing the site. I never even knew there was a limit. I wonder if it resets after a particular amount of time or is just gone. You can see below I just got a little too excited to play around

author: free_electron
author_rank: Super Contributor
timestamp: April 28, 2015, 11:19:10 pm
content: Quote from: zerorisers on April 24, 2015, 01:48:37 pmyes, there are FTDI chips from TI just like you can buy Atmels from microchip ...

author: zerorisers
author_rank: Regular Contributor
timestamp: April 29, 2015, 12:09:12 pm
content: I probably should have phrased that better xD 'an FTDI like chip from TI*'

author: Wilksey
author_rank: Super Contributor
timestamp: April 29, 2015, 05:20:07 pm
content: Quote from: free_electron on April 28, 2015, 11:19:10 pmYou almost very nearly could at one point!But yeah, you mean USB to UART chip?

author: miguelvp
author_rank: Super Contributor
timestamp: April 30, 2015, 05:57:26 am
content: Quote from: zerorisers on April 29, 2015, 12:09:12 pmNot sure about TI, but cypress has a drop in replacement with their CY7C65213http://www.cypress.com/?id=4&rID=83118https://www.eevblog.com/forum/projects/cypress-cy7c65213-a-pin-compatible-ft232r-replacement/msg621159/#msg621159
TIAs output pole - Page 1
Forum section: electronics / beginners

author: TIAR
author_rank: Newbie
timestamp: April 30, 2025, 09:04:08 pm
content: I derived the transfer function of a TIA with a single resistive feedback and a load capacitor at the output. However, the pole location obtained from the simulation consistently differs by a factor of 10 from the one predicted by the derived function. The simulation results suggest that the pole is almost entirely determined by the load capacitor. Would it be reasonable to interpret this as the result of a very low output resistance, such that the pole is effectively dominated by the capacitor?

author: RoGeorge
author_rank: Super Contributor
timestamp: May 01, 2025, 09:35:40 am
content: Hard to say without a schematic and its components values. In case you are sure the manually calculations are correct, yet the simulation is 10 times different, then maybe the SPICE model of the opamp is not accurate enough.

author: tggzzz
author_rank: Super Contributor
timestamp: May 01, 2025, 10:11:51 am
content: Quote from: TIAR on April 30, 2025, 09:04:08 pmWe aren't mind readers.Show your derivation.Show your Spice schematic and results.This is a well-studied topic since it it commercially important. Compare what you've done with TAoE (including x-chapters) and Phil Hobbs' bookhttps://electrooptical.net/Building_ElectroOptical_Systems/"Building electro-optical systems : making it all work" is directly relevant since "[it is] intended in the first instance for use by oppressed graduate students".
Tiggering a TRIAC - Page 1
Forum section: electronics / beginners

author: FrankT
author_rank: Regular Contributor
timestamp: June 17, 2015, 08:46:20 pm
content: I'm breadboarding my AC Dimmer circuit, which is basically the one on this page...http://playground.arduino.cc/main/ACPhaseControlI've got the zero crossing circuit/code working and I can see output on the optoisolated triac driver (MOC3052), but the main triac doesn't seem to be firing.I've tried to simplify (see attachment) but still nothing.What is it that fires a triac? From what I've read, it is current into G, but the data sheets I've been reading confuse me. I'm using a BT136-600, but I don't know what to read from the datasheet. The freescale application note, an2839, says I should use up to 3 times the gate current.What am I missing?

author: German_EE
author_rank: Super Contributor
timestamp: June 17, 2015, 08:52:17 pm
content: I'm not sure about that 1,5K resistor. All of the triac circuits I've seen have had large currents flowing through the device and that's what keeps the device on after it's been triggered. If you want to keep experimenting at low voltage then take out that resistor and replace it with a 12V bulb and a battery.
TIL311 Hex Display - Page 1
Forum section: electronics / beginners

author: sonnytiger
author_rank: Frequent Contributor
timestamp: February 22, 2013, 02:49:33 am
content: Found four of these nice Hex Displays at school the other day, what I believe to be the date code says 8631 (The only other text on them is TIL311 and KOREA), so I would assume 31st week of 1986 O0? If so, cool! Any way they are really nice, bright and nicely made, with a clear red casing letting you see the individual leds and the control chip, they seem to go for a pretty penny on ebay as well (200+ for 50 from China). At any rate I though they were cool, and wanted to share them, maybe catch some interesting tidbits about them from the wise bearded electronics guys out there. I was testing them using my arduino and they work fine.http://www.ti.com/lit/ds/symlink/til311.pdfSorry no pictures, camera is in an unreachable location right now!

author: westfw
author_rank: Super Contributor
timestamp: February 22, 2013, 09:49:20 am
content: Those are old. One of the hobbyist cdp1802 projects in the late 70s used them for the hex display (although the original "COSMAC Elf" used a similar HP display.)Nowadays you can put together a 5x7 dot matrix and a microcontroller and produce a similar display for a lower cost.

author: sonnytiger
author_rank: Frequent Contributor
timestamp: February 22, 2013, 10:45:17 am
content: No doubt, still very cool for their nice build quality and RETRO factor though!

author: SeanB
author_rank: Super Contributor
timestamp: February 22, 2013, 04:22:32 pm
content: You get one with a built in decimal counter, and you could make a counter using just the chips, even a clock as it had the BCD outputs as well.
Time Delay Circuit Help :) - Page 1
Forum section: electronics / beginners

author: masterp0gi
author_rank: Newbie
timestamp: September 22, 2015, 11:19:21 am
content: How can I synchronize output pulse with an irregular input interval.. ex. input = pulse1 - 0, pulse2 - 0.3sec, pulse3 - 0.7sec and the output pulse interval should be 0.3sec from each pulse. ex. output pulse1 = 0.3sec, pulse2 = 0.3sec, pulse3 = 0.3sec

author: alsetalokin4017
author_rank: Super Contributor
timestamp: September 22, 2015, 06:15:02 pm
content: Monostable 555 (one-shot) with appropriate timing components ?

author: Cliff Matthews
author_rank: Unknown
timestamp: September 24, 2015, 02:31:56 pm
content: 100nF and 2.7k ohms = 297msBTW, lots of standalone apps (or web calculators) for 555's Eg:http://www.ohmslawcalculator.com/555-monostable-calculator
Time invariant/variant system - Page 1
Forum section: electronics / beginners

author: nForce
author_rank: Frequent Contributor
timestamp: January 01, 2018, 02:01:09 pm
content: Hello,I am watching these videos (for example one is here:.I don't understand why do we for the 1.2 example writex(cos(t)-t0)and notx(cos(t-t0))?This guy said that t0 is a constant and we don't insert it in cos term. But I don't understand why?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 01, 2018, 05:32:20 pm
content: At a glance that looks wrong: unit mismatch. cos()'s output is dimensionless, while t and t0 are presumably time dimensioned. You can only add units of the same type.cos's argument (input) is also dimensionless, so it's still wrong, unless there's an implied unit angular frequency (i.e., "cos(w*t)" where w == 1).It's more rigorous and general to apply these considerations. I don't feel like reviewing the video at this moment, sorry, but maybe this will give some insight.Tim

author: orolo
author_rank: Frequent Contributor
timestamp: January 01, 2018, 06:35:28 pm
content: Quote from: nForce on January 01, 2018, 02:01:09 pmWell, you need to be a bit careful with the notation here. A system transforms a time-dependent inputx(t) into a time-dependent outputy(t).Consider the t0-delay system, call itD: for a signalx, you have thatDx(t) =x(t-t0).Consider the cos system, call itC: for a signalx, you have thatCx(t) =x(cos(t)).The systemCwill be time-invariant ifCD=DC, that is, if you cannot tell if a signal was delayed after or before entering the system.So let us take an arbitrary signalxand compareC(Dx) andD(Cx). If you can distinguish them, the system is not time-invariant.C(Dx)(t) =Dx(cos(t)) =x(cos(t) - t0)D(Cx)(t) =Cx(t - t0) =x(cos(t-t0))SoCis not time invariant. Here you can see where the t outside the cosine comes from.
Time to start, move, and stop a stepper motor - Page 1
Forum section: electronics / beginners

author: gamozo
author_rank: Regular Contributor
timestamp: January 02, 2013, 07:51:22 pm
content: I'm having a bit of a discussion at work here about making a robot to play foosball 'perfectly'.Assuming that computing the speed and curvature that the ball is travelling is trivial, we've estimated thatwe need to move the foosball players up to about 5cm (from dead start to dead stop) in 20 milliseconds.How hard would something like this be to do with a stepper motor? Is there any way to calculate this based on stepper motor datasheets?-Brandon

author: Kremmen
author_rank: Super Contributor
timestamp: January 02, 2013, 09:41:07 pm
content: The calculation would not be hard but more info is needed.Firstly, performing the motion in 20 ms using a time-optimal trajectory means accelerating for 10 ms and braking for the other 10 ms.During acceleration the gizmo moves 2.5 cm (half way), and from the equation S = at^2 we get acceleration by simple rearrangement:a = 0.025m / 0.0001s^2 = 250m/s^2 ~25.5gNext you need to know the mass to accelerate at that rate. From that you can calculate the force needed (F = ma), and then from that the motor torque required to generate that much linear force over the drivetrain.The acceleration being that high, i don't think you will find an easy solution although i don't consider it impossible. You can forget all run-of-the-mill iron steppers because their self-mass and inertia will preclude that kind of acceleration. You would need a disc rotor or basket rotor motor, and those babies are neither common nor necessarily cheap. Kollmorgen at least makes basket rotor servos that are designed for this kind of application. But they have their price...
Timer interrupt FIRQ on a 68B09EP - Page 1
Forum section: electronics / beginners

author: powerchisper
author_rank: Contributor
timestamp: April 03, 2019, 02:31:03 pm
content: Hello friends.I am not sure what this means.In the PCB I am trying to fix, the manual says that the CPU has a timer interrupt signal used as a heartbeat for the system.The clearing of the timer interrupt is done by reading the dip switches ( a 74hct245 to which those switches are connected to ).Could someone explain a little bit this "clearing"??Any help would be appreciated.

author: johnkenyon
author_rank: Regular Contributor
timestamp: April 03, 2019, 03:55:43 pm
content: As a guess,The output enable line for the buffer is probably triggers a reset (=clear) of a flipflop which is turned on when the counter/timer that does the timer FIRQ times out.So the FIRQ routine does whatever it does, and then does a dummy read of the DIP switch buffer to clear the interrupt at source, before executing a return from interrupt instruction.This may seem strange but, it reduces the chip count/complexity of the board.1) The software will only read the DIP switches when an interrupt is not active, (so there is nothing to reset).2) It removes the need to decode another address or to decode a write to a specific address - the decoding of the buffer read signal is there already (meaning it is "free", no additional cost)
Timer not working properly?? - Page 1
Forum section: electronics / beginners

author: RobH
author_rank: Regular Contributor
timestamp: October 26, 2022, 02:15:25 pm
content: I have found another noise circuit in the same book as the previous circuit, and is an extension of it.(The previous circuit did work after getting help from here thanks)This circuit uses x2 555 timers along with a LM741The 1st timer / 555 is called 'a noise duration timer', and it is supposed to work like this:When a noise is picked up by the electret mic the beeper sounds, and in theory when the noise stops , so should the beeper. This is done by the voltage going low, when the noise stops, using the reset pin on the 1sr timer / 555The voltage on pin 4 without noise is 9V and when it goes low, it goes down to practitly 0V, but doen't stop the noise of a beeper.The x2leds which are in circuit with each timer do come on and go off as soon as the noise stops, but as soon as the beeper is connected and activated it goes on forever.Qoute:'When the Noise Duration Timer reaches the end of its' period, its' output will go low which will shut down the external noise-making device. It will pass through a coupling capacitor to the Pause Duration Timer , 2nd 555 /timer, and the sudden drop in voltage will trigger it'End QuoteOn pin 2 of the 2nd timer I get 9v with no noise, but when I tap the mic the voltage goes up to 10v and then back down to 8V, but with the beeper connected to pin3 of the 1st timer, after going up to 10v , it goes down to just 9vWhat do I need to do to put this rightThanks

author: bidrohini
author_rank: Regular Contributor
timestamp: November 01, 2022, 03:58:12 am
content: Hi, did you check the beeper that you're using? Are you sure that it is good?

author: Ian.M
author_rank: Super Contributor
timestamp: November 01, 2022, 07:24:11 am
content: Quote from the book in question ("Make: More Electronics" by Charles Platt), at the end of the chapter containing this circuit:Quote
Tin a soldering iron copper tip (Antex 0.12mm) - Page 1
Forum section: electronics / beginners

author: sdancer75
author_rank: Frequent Contributor
timestamp: March 31, 2019, 05:10:46 pm
content: I bought a copper tip no 57 (0.12mm) from my Antex XS25https://www.antex.co.uk/products/replacement-bits/50-bits-for-xs-mlxs/b005770/No matter what, I can not tin this tip. The solder is becoming like small balls and it does not stay on the tip.Is this normal for unplated copper tips? The tip is brand new. What seems to be the problem here?From the photo attached does, it seems oxidized?

author: tautech
author_rank: Super Contributor
timestamp: April 01, 2019, 04:21:48 am
content: Quote from: sdancer75 on March 31, 2019, 05:10:46 pmYes, or more likely blued like a rifle barrel.Pop it in a drill and shine the very last mm or so of the tip with some very fine emery or steel wool.That might be wrong but that's what I'd do if solder won't take to it. Still you might have to experiment with different fluxes/solders to get it to tin to your liking.

author: Ian.M
author_rank: Super Contributor
timestamp: April 01, 2019, 06:08:33 am
content: After cleaning the tip of the tip to bright copper as Tautech advised, *DONT* put it in the iron, as by the time it heats up enough to melt solder with its very small cross section it will have oxidised again*. Wrap its shank with a strip of paper for thermal insulation, and pop it in a metal jawed clamp (or a pair of pliers with a rubber band round the handles) to stop it rolling away from you on your bench, then tin it with solder and flux as-if it was a component pin using a heavy duty tip in your iron.* The only way tinning it in the iron can work is if you use solder paste applied cold and wrap the tip tightly in aluminum foil to hold the paste against it and exclude air as it heats up.

author: macboy
author_rank: Super Contributor
timestamp: April 01, 2019, 03:06:42 pm
content: Quote from: Ian.M on April 01, 2019, 06:08:33 amI agree that a new tip must be tinned at the instant it reaches melting temperature. If you wait too long (even a few seconds too long) it oxidizes and becomes nearly impossible to tin.However, I have always had success with just installing the tip, turning on the iron, and continuously trying to melt some good solder wire (Kester 44 60/40, nice RA flux) to the heating tip. When it reaches melting temperature, the solder will flow onto the tip. This works even better if you can add some flux to the tip beforehand.

author: sdancer75
author_rank: Frequent Contributor
timestamp: April 01, 2019, 05:16:59 pm
content: thank you all.I followed your instructions and I tinned my tip with the following method.
Problem in TINA simulatiing astable LED flasher - Page 1
Forum section: electronics / beginners

author: alanc
author_rank: Newbie
timestamp: November 02, 2017, 12:39:05 pm
content: Hello, I'm new to electronics and eevblog forum (although I already watched a lot of Dave's video). I am trying to figure out how the astable circuit works. I created a circuit in TINA v11 and simulate it using Transient Analysis but the result has problem.When I set the end time to 2s, the result looks somewhat OK. VF1 and VF2 will oscillate. But when I set the end time to larger value like 10s, both VF1 and VF2 always at same level. Circuit and simulation results attached.Is the problem of my circuit? Or I need to adjust some TINA parameters to make it right?Sorry in advance if the post should not be here or anything inappropriate.

author: jimmc
author_rank: Frequent Contributor
timestamp: November 02, 2017, 01:18:30 pm
content: It's a common problem with simulators that oscillators do not start without help. In the real world circuit unbalance or noise is usually enough to set things off.The simplest solution is to add a timed switch from one base to ground, closed for say 1mS from time zero and open after that.This will provide the 'kick' to start the simulated oscillator running.Jim

author: tszaboo
author_rank: Super Contributor
timestamp: November 02, 2017, 01:21:56 pm
content: It is just the way a SPICE simulation works. It is not really suitable to work with digital-ish circuits. But try the Steady state solver, it is more relevant to evaluate this.

author: Zero999
author_rank: Super Contributor
timestamp: November 02, 2017, 01:29:05 pm
content: Change the value of one of the resistors or capacitors by 0.1.

author: alanc
author_rank: Newbie
timestamp: November 02, 2017, 01:33:24 pm
content: I have tried this before but no help. I don't know why. But thanks anyway

author: alanc
author_rank: Newbie
timestamp: November 02, 2017, 01:35:50 pm
content: Thanks Jim. I will try this.

author: alanc
author_rank: Newbie
timestamp: February 06, 2019, 02:28:15 pm
content: Hi, I finally fixed the problem. The simulation for longer period (e.g. 10s) is now normal, and even better, the simulations are consistent across different time periods. I think it really gives trusted result.Back to the day I suspected it is because the precision of the simulation but don't know how to adjust it. I think TINA adjusts it according to the simulation period or singal frequency or something like that. Now I find that the Max time step is the key. For Transient simulation I set the parameter to 50u (I tested 100u also ok) and the value depends on your need.Hope this help anyone have similar problem.
TINA simulation program - Page 1
Forum section: electronics / beginners

author: medical-nerd
author_rank: Regular Contributor
timestamp: October 08, 2017, 12:10:57 pm
content: HiyaI'm starting to use the free TINA-TI analog simulation program from Texas Instruments.Is the Student version of TINA from Designsoft (49 Euros) any better?I'm interested in simulation of basic analog RF circuits at the moment.Cheers

author: Zero999
author_rank: Super Contributor
timestamp: October 09, 2017, 02:42:02 pm
content: Sorry, I've no idea. I used a pirated version of TINA, many years ago, whilst I was a student, before TI bought it. I thought it was OK but preferred LTSpice, which most people here use.

author: BigBoss
author_rank: Regular Contributor
timestamp: October 09, 2017, 02:48:15 pm
content: I recommend that software.It looks like ADS and it's pretty good.http://dd6um.darc.de/QucsStudio/screenshots.html

author: Neilm
author_rank: Super Contributor
timestamp: October 09, 2017, 06:40:38 pm
content: The last time I used TINA it had to have an IC on the schematic and some of the analysis options either didn't work or were disabled and didn't tell me. I found it more or less OK but LTSpice was more powerful hence I use that.

author: ahbushnell
author_rank: Frequent Contributor
timestamp: October 09, 2017, 08:29:28 pm
content: I like Tina. I have a current full up purchased version ($500). It works well.Andy

author: medical-nerd
author_rank: Regular Contributor
timestamp: October 10, 2017, 08:16:05 am
content: HiyaThanks to you all. I have now looked at QUCS and it looks very interesting. The tutorial by Gunthard Kraus covers many areas I'm interested in. I will see how far a combination of this and ELSIE gets me.LTSpice is a powerful program but my time is very limited and from the comments on this forum I don't think I will have enough to learn the complexities of this. I was looking at a more 'plug and play' approach which is why I was first attracted to TINA-TI, but can't justify the cost of a full licence yet, which is why I was looking at the student version.Cheers