hybridfree/eevblog-posts huggingface dataset:
How to find the .lib file for PSPISE? - Page 1
Forum section: electronics / beginners

author: wenyi
author_rank: Newbie
timestamp: October 24, 2023, 08:35:55 pm
content: What should I do when I can't find a .lib file for simulating a circuit on the official website (e.g. Texas Instruments)?I use PSPISE for simulation. .lib file used to simulate. but I cannot find them in the official website.Like CD74HCT193E CTR, I cannot find the .lib file.I am new for circuit design. Thank you for help me.

author: magic
author_rank: Super Contributor
timestamp: October 24, 2023, 11:01:05 pm
content: AFAIK if TI doesn't show a model download link on some product's page (http://ti.com/product/XY1234) then they don't have a model for it. It happens.Then you could look for models of same part number from other manufacturers, or just search the Internet. If nothing exists than you're SOL.

author: drago462
author_rank: Contributor
timestamp: November 21, 2023, 07:30:16 am
content: If you can't find a .lib file for a component like the CD74HCT193E on Texas Instruments' website for your PSpice simulations, try looking at other electronics databases or forums where people share such files. You could also explore using generic libraries in PSpice that might have a similar component. And don't hesitate to ask around in electronics communities or reach out to Texas Instruments' support for help. As you're new to circuit design, tackling this issue can be a great learning experience.
How to find the LT1575 pole capacitor and zero resistor by using LTspice - Page 1
Forum section: electronics / beginners

author: andrewsh
author_rank: Newbie
timestamp: March 24, 2024, 02:09:02 pm
content: Hi! Can I know how to find my pole capacitor and zero resistor by AC open-loop. The stability : AC open-loop Bode plot has at least 45 degrees of phase margin at both 1% and 100% of the assigned Maximum Load Current.I don't know how to get C3, C4 and R4.

author: aliarifat794
author_rank: Regular Contributor
timestamp: March 24, 2024, 02:21:53 pm
content: Have you posted your question to LTspice group?

author: andrewsh
author_rank: Newbie
timestamp: March 24, 2024, 02:24:13 pm
content: Sorry, I don't know that it has this group. How to post it into LTspice group?Thank you for your reminding

author: RFDx
author_rank: Regular Contributor
timestamp: March 25, 2024, 04:41:45 am
content: Quote from: andrewsh on March 24, 2024, 02:09:02 pmTake a look at the datasheet of the LT3150 fast transient LDO controller. It contains all the required info to determine the frequency compensation component values incl. the associated poles and zeros.https://www.analog.com/media/en/technical-documentation/data-sheets/3150f.pdf
How to find the right diode? - Page 1
Forum section: electronics / beginners

author: micnolmad
author_rank: Newbie
timestamp: February 24, 2016, 12:38:47 pm
content: Diodes are hard! A resistor is easy, there are many apps and articles on how to use them and so.As a newcomer to diodes I am struggling to find a good way to find the right diode for the job. By find I mean some sort of tool, app or db with some search parameters to narrow it down. I do understand the math the various elements of a diode once I know what the characteristics it should have how do proceed? There must be some form of lookup tool?Thanks

author: Adam60
author_rank: Regular Contributor
timestamp: February 24, 2016, 12:51:20 pm
content: Look at supplier sites such as Digikey. Diodes can be filtered to your specifications as they give you a lot of choices and allow you to choose the characteristics which fit your needs.

author: Seekonk
author_rank: Super Contributor
timestamp: February 24, 2016, 02:29:49 pm
content: You can pretty much get by on a half dozen diodes. That said there is a reason for each diode. Things are complicated further when some diodes don't exactly match their specifications. Forward voltage really irks me when I see it mentioned in posts as .25V and .6V and in actual applications it is nowhere near that.

author: Audioguru
author_rank: Super Contributor
timestamp: February 24, 2016, 03:14:27 pm
content: A 1N4148 general purpose silicon diode is 0.6V at a current of about 700uA. Its maximum allowed reverse voltage is 75V and its maximum allowed continuous current is 300mA.A 1N5817 Schottky diode is 0.25V at a current of about 20mA. Its max allowed reverse voltage is 20V and its maximum allowed average rectified current is 1A.The above diodes switch very quickly.A 1N4001 rectifier has a maximum allowed reverse voltage of 50V and a max allowed average rectified current of 1A but its max allowed momentary current is 30A! It switches very slowly so is used only for DC or for 50Hz and 60Hz mains rectifying.

author: 3DA502
author_rank: Newbie
timestamp: February 24, 2016, 03:47:47 pm
content: all kind of them need be know

author: Seekonk
author_rank: Super Contributor
timestamp: February 24, 2016, 07:15:10 pm
content: I use a SB5100 5.0A 100V SCHOTTKY diode generic and cheap. Spec say .52V forward at 1A in real life about .665 and it gets worse with more current. Once you get over 50V there isn't much advantage other than speed.

author: micnolmad
author_rank: Newbie
timestamp: February 25, 2016, 01:58:52 pm
content: Thank you all for participating.. Adam 60, ty. Clear and useful answer.The rest of the posts felt more like a private discussion then an answer to the OP or am I just not getting the meaning?
How to fit R to a "time base clock"? - Page 1
Forum section: electronics / beginners

author: bitman
author_rank: Unknown
timestamp: December 06, 2022, 03:38:10 pm
content: I'm having a hickup with a datasheet - LED driver, nothing fancy or anything:https://datasheet.lcsc.com/lcsc/1811021420_Holtek-Semicon-HT1621B_C7873.pdf- the HT1621 chip. I'm trying to find how to control the current for the LEDs.In this image, there's a variable resistor between VDD and VLCD. It's explanation is "Adjust R (external pull-high resistance) to fit user's time based clock" and I have no idea how to do that. I don't see a formula. The IC technically has adjustable clocks, but they're all reduced to 32KHz if I understand the datasheet correct, so this makes no sense to me and seems an important part is missing from the datasheet.Note, this is definitely a "Chinese chip" and with everything that often comes with that, I'm wondering if I'm heading down the wrong road here. All I want to do is control some LEDs, and I am out of MAX7219s

author: wasedadoc
author_rank: Super Contributor
timestamp: December 06, 2022, 03:46:04 pm
content: Quote from: bitman on December 06, 2022, 03:38:10 pmThis is an LCD driver and LCDs arevoltagedriven. Why do you write "LEDs" and "current"? MAX7219isfor driving LEDs.

author: bitman
author_rank: Unknown
timestamp: December 06, 2022, 04:52:04 pm
content: Quote from: wasedadoc on December 06, 2022, 03:46:04 pmAnd there perhaps lies my screwupThanks for pointing out what my weak eyes obviously missed.

author: EPAIII
author_rank: Super Contributor
timestamp: December 08, 2022, 06:56:08 am
content: LCD displays are adjusted by just looking at them and adjusting for the most readable display. They are giving a typical value of 15 KOhms. You can use a 20 KOhm pot or even a 50 KOhm pot. It is adjusted after the circuit is constructed and it is running.

author: ledtester
author_rank: Super Contributor
timestamp: December 10, 2022, 01:52:37 pm
content: Holtek Semiconductor is a very well established Taiwanese chip design company which has been around since the early 80's.
How to fix a clipped signal - Page 1
Forum section: electronics / beginners

author: tiofilo75
author_rank: Contributor
timestamp: June 01, 2013, 07:13:56 am
content: So I am trying to amplify a sinusoidal signal to 4vpp using a multistage amplifier and I am able to get the positive 2vp but my negative side is clipped at -1.4v. I am using a FET for my 1st stage so that I may have a high input impedance, a common emitter BJT in the second stage to invert the signal from the 1st stage and finally a common collector BJT in the last stage so that I may have a low output impedance. I tried changing some resistor values to make sure that my Q point has enough room to swing in the positive and negative region by my signal is still clipped. Any info would be nice, thanks.

author: qno
author_rank: Frequent Contributor
timestamp: June 01, 2013, 08:15:10 am
content: To get most out of your circuit aim for Q1 collector voltage of half the power supply.The same is true for the emitter of Q2.You should redesign your DC set-up.

author: Paul Price
author_rank: Super Contributor
timestamp: June 01, 2013, 02:59:40 pm
content: I don't see why you just don't use a rail to rail input/output type of Op-Amp to do this this job eliminating scores of resistors and capacitors and circuit sprawl?"I am using a FET for my 1st stage so that I may have a high input impedance"You are not going to get very hi-impedance at the input, the two biasing resistors present themselves to any input driving source as a single paralleled resistor shunted to ground at the gate of the FET. Is this impedance high enough for you?I tried changing some resistor values to make sure that my Q point has enough room to swing in the positive and negative region by my signal is still clipped.I agree with the last reply...so try changing them some more to set device output pins at power supply midpoint.My simpler circuit that solves all these problems: (attached)Note: in attached circuit, R1 should be approx 1.1k to start with and should give close to 6V at emitter Q2.Ok, so it is not really an op amp!
How to fix okamoto surface grinding machine controller DX48 - Page 1
Forum section: electronics / beginners

author: intelindahouse
author_rank: Newbie
timestamp: June 13, 2025, 10:46:38 pm
content: Hi all,I'm trying to repair the DX48 controller from an Okamoto surface grinding machine. The machine originally had auto downfeed via a servo motor (Kawamata, 400W, 75V) controlled through this board. The board also includes a separate power supply (DXPW board) that supplies power to the DX48 and servo section.Here’s what I’ve done:I connected AC 120V to the power supply board (Live, Neutral, and Earth).Also connected the motor wires (U, V, W) and encoder feedback cable to the DX48.As soon as I power on, the 10A fuse blows instantly (even if the motor is disconnected in some tests).In earlier attempts, some MOSFETs on the power board got shorted and were replaced.I've tried testing with and without the MOVs, motor, and encoder connected — same result.I suspect the issue could be:A bad gate driver circuit or shoot-through conditionShorted components downstream of the DC busFaulty control logic on the DX48Has anyone worked on this controller or encountered a similar issue with the DX48 and DXPW boards? Any help tracing the root cause or even a partial schematic would be hugely appreciated.Thanks!

author: ahsrabrifat
author_rank: Regular Contributor
timestamp: June 14, 2025, 03:17:40 pm
content: Did you check for broken traces?

author: intelindahouse
author_rank: Newbie
timestamp: June 16, 2025, 02:56:05 am
content: Yes. The traces are fine

author: edpalmer42
author_rank: Super Contributor
timestamp: June 16, 2025, 03:26:51 am
content: You could try a dim-bulb tester. Search the forum for info. It should prevent the fuse from blowing and hopefully help you find the short.

author: intelindahouse
author_rank: Newbie
timestamp: June 16, 2025, 02:51:09 pm
content: Hi. That's what I did today. So when I remove the transformer it doesn't show a short. When I connect it it shows a short. I checked the transformer primary and secondary and it's showing a value of 38. I'm confused now
How to fix TO-126 (a.k.a. SOT-32 a.k.a. TO-225AA) to heatsink without shorting - Page 1
Forum section: electronics / beginners

author: Dabbo56
author_rank: Contributor
timestamp: October 17, 2022, 06:30:29 pm
content: This is a small, through-hole transistor package. There is a hole for fixing to a heat sink. I'm using a 3mm bolt, having tapped a hole in the heat sink with my tap-and-die set, and using a mica insulator. BUT, I'm not happy because the metal collector pad is incredibly close to the fixing hole. Checking for connectivity between the heat sink and the collector I'm getting intermittent short, possibly due to barely visible swarf from the tapping process coming between the bolt and the collector pad. Is there an alternative e.g. plastic bolts? Am I using the right technique?

author: Kleinstein
author_rank: Super Contributor
timestamp: October 17, 2022, 06:38:18 pm
content: Normally there is sufficient insulation around the hole, but it may depend on the parts / manufactuer. A more flexible silicone pad instead of the thin mica plus thermal grease could also be an advantage, as under pressure it moves closer to the hole. A clean surface of the heat sink may be needed to avoid damage to the insulator. It helps to add a bevel to the hole before tapping.

author: Benta
author_rank: Super Contributor
timestamp: October 17, 2022, 06:49:18 pm
content: Quote from: Kleinstein on October 17, 2022, 06:38:18 pm+1Swarf should not be there, sloppy machining/tapping.

author: strawberry
author_rank: Super Contributor
timestamp: October 17, 2022, 07:10:34 pm
content: dull drill bit presure lift edges around hole

author: Benta
author_rank: Super Contributor
timestamp: October 17, 2022, 08:47:00 pm
content: Quote from: strawberry on October 17, 2022, 07:10:34 pmDoesn't matter. A hole should always be bevelled/chamfered. Anything else is sloppy work.

author: Dabbo56
author_rank: Contributor
timestamp: October 17, 2022, 08:59:06 pm
content: That’s the answer

author: David Hess
author_rank: Super Contributor
timestamp: October 18, 2022, 06:48:19 pm
content: Quote from: Dabbo56 on October 17, 2022, 06:30:29 pmThreading and attaching directly to the heat sink is not recommended because it distorts the surface making it difficult to get good contact and risking damage to the insulator.

author: Benta
author_rank: Super Contributor
timestamp: October 18, 2022, 07:33:50 pm
content: Quote from: David Hess on October 18, 2022, 06:48:19 pmWhich chamfering the hole fixes. Works for engine blocks, gearboxes, all kinds of precision mechanics. And yes, also for power transistors on a heat sink.

author: David Hess
author_rank: Super Contributor
timestamp: October 19, 2022, 12:09:58 am
content: The old classicMotorola application note 1040has quite a bit to say about TO-225 mounting.
How to fully saturate MOSFET output - Page 1
Forum section: electronics / beginners

author: help_me_pick_username
author_rank: Contributor
timestamp: November 16, 2019, 02:50:29 am
content: I want to fully drive a 30N06L MOSFET. I have an ESP8266 driving a 10w LED through the MOSFET. The ESP has 3.3v logic levels, and the LED runs at 12v. I am controlling the LED by PWMing the MOSFET gate. My problem is, the 3.3v output level of the esp does not seem to be enough to fully saturate the MOSFET output.I'm pretty sure that a dedicated MOSFET driver IC is the solution to this, but since I don't have any, and I don't want to wait another few weeks for it to arrive from online, I was wondering if there was some other solution to my problem. (Can I maybe use a BJT to drive the MOSFET at a higher voltage level...?)

author: Audioguru again
author_rank: Regular Contributor
timestamp: November 16, 2019, 03:47:22 am
content: The datasheet of your 30N06L Mosfet shows that it works fairly well when its Vgs is 5V but gives full power when the Vgs is 10V. Some of them work poorly with a Vgs of only 3.3V.A gate driver IC is not a voltage booster generator, instead it is a circuit that can produce a fairly high current that can quickly charge and discharge the high gate capacitance at a high frequency without boosting the gate voltage.If you have a power supply that is a littler higher than 5V or 10V then a transistor might be able to be driven from the 3.3V signal and give 5V or 10V pulses to the Mosfet gate.

author: help_me_pick_username
author_rank: Contributor
timestamp: November 16, 2019, 04:09:17 am
content: I have a 19v power source powering the whole thing. So should I just be able to drive the MOSFET with a signal from a transistor?

author: Peabody
author_rank: Super Contributor
timestamp: November 16, 2019, 05:33:14 pm
content: With the high voltages involved here, it seems the safe transistor to drive from the ESP8266 would be an NPN. And all that NPN can really do when you turn it on is ground its collector. To me, that strongly suggests using a P-channel mosfet, which would turn on and apply the full 12V to the LED when its gate is grounded by the NPN collector. It's not obvious to me how you would make this work using another transistor to drive the N-channel mosfet. I'd like to see a schematic of how that would be done.
How to fully test 2nd hand keysight n9020a spectrum analyzer to find any issue? - Page 1
Forum section: electronics / beginners

author: nicegirl
author_rank: Contributor
timestamp: March 06, 2022, 03:18:51 pm
content: This is the first post in eevblog.I bought a second hand keysight n9020a spectrum analyzer,There's no quality warranty,but I can ask for refund if I found any quality issue in 1 week.I already read some manual from keysight website,but has no idea how to test the spectrum analyzer for finding any hide quality issue.Question:how to fully test spectrum analyzer like keysight n9020a,to make the machine works well in next 5years?

author: bob91343
author_rank: Super Contributor
timestamp: March 06, 2022, 05:09:47 pm
content: Isn't there a section in the manual for Performance Verification?

author: geggi1
author_rank: Frequent Contributor
timestamp: March 06, 2022, 05:37:58 pm
content: Check the manuals for a self test mode.https://www.testunlimited.com/pdf/an/keysight_N9020A_service%20guide.pdf
How to gauge wattage, from input or output - Page 1
Forum section: electronics / beginners

author: Rolomoto
author_rank: Newbie
timestamp: February 28, 2016, 07:05:26 pm
content: I'm trying to figure out how many watts a power supply for a router is pulling. It says:input 120VAC 0.58aoutput 12 VDC 1.8aWhich one would you base a wattage calculation on?Thanks

author: TheAmmoniacal
author_rank: Unknown
timestamp: February 28, 2016, 07:22:47 pm
content: Try to measure it, don't trust the markings.What device do you want to know the power consumption of?It should mean that your PSU can draw 0.58 A max from the 120 VAC supply (of course it will most definitely always draw a lot less), and can supply 1.8 A max at the 12 VDC output.The power usage of your PSU will depend on the power usage of your router. The power consumption of your router will be changing constantly, depending on what it's doing.You can expect your PSU to always draw about 15% more power than your router, assuming it's 85% efficient (which is a reasonable figure if it's an SMPS).

author: michaeliv
author_rank: Frequent Contributor
timestamp: February 28, 2016, 08:09:07 pm
content: As the previous poster pointed out, the difference in power is due to inefficiency.However in your case it says it can draw up to 70W from the wall but output max 22W.I'm guessing the difference is because it can draw 70W when plugging it into the wall. There will be a 70W draw while the caps are charging for micro/mili seconds.So depending on what you need the power calculation for, use the corresponding figure.

author: Augustus
author_rank: Regular Contributor
timestamp: February 28, 2016, 11:01:48 pm
content: Usually somewhere in the range of 5 ... 12 W for a typical consumer router (drawn from the wall).

author: uncle_bob
author_rank: Unknown
timestamp: February 29, 2016, 01:43:48 am
content: HiSimple answer for most small gizmos:The output is spec'd as DC. There is no power factor, amps X volts gives you power.The input is rated simply in terms of current. That matters for fusing so it's a relevant spec. As mentioned above, the power factor on a lightweight transformer is likely pretty terrible. Maybe half of the current goes to power, the rest is just wasted energy. The efficiency of the device is on top of that. If you have a 70% efficiency on top of the power factor it all sums up.Next up you have the somewhat odd fact that even on resistive load stuff, they can't seem to get the numbers right. If you spend some time checking appliances, they pretty much never pull to much current. They often pull 20 or 30% less current than they should. Why should? If I bought a 500W toaster oven ... it should be 500W. In this case it's both tolerances and marketing.Bob
How to get 0..10V from DAC? - Page 1
Forum section: electronics / beginners

author: ondreji
author_rank: Contributor
timestamp: February 08, 2012, 04:57:33 am
content: I need to generate two signals between 0V and 10V. I use MCP4922 DAC and I haven't decided on output op-amp and voltage reference. Micro runs on 3.3V (abd system have 12V and 5V as well) so I can use:3.3V for DAC, Vref = 2.5V and x4 gainor 5V for DAC, Vref = 5.0V and x2 gain (and level convertor for SPI bus)or 5V for DAC, Vref = 2.5V and x4 gain (and level convertor for SPI bus)I did few experiments (with LM324) but I haven't noticed any difference (apart from level convertor "complication").So, which configuration would you choose and why?Thanks

author: Psi
author_rank: Super Contributor
timestamp: February 08, 2012, 06:26:23 am
content: I'd probably use the first option, just to eliminate the need for the level converter.

author: Bored@Work
author_rank: Super Contributor
timestamp: February 08, 2012, 09:16:13 am
content: Not having to use a level converter is a good thing.On the other hand, a higher reference voltage means you can have a better SNR and less offset in the system. Your LSB is higher above the noise floor. If this is relevant depends on the noise in your system. A lower gain in the following gain stage also means offset amplification is lower, and less distortion, in case it matter in your system.You decide what matters more.

author: Unknown
author_rank: Unknown
timestamp: February 09, 2012, 12:33:19 am
content: Agreed with BaW. If analog performance is critical, go with the lower gain. A level translator won't have much (any) impact on analog performance, extra gain and lower Vref may. If analog performance is acceptable either way, go for the simplest solution with the lowest parts count.

author: ivan747
author_rank: Super Contributor
timestamp: February 09, 2012, 02:01:52 am
content: Also remember that current consumption is much higher when an IC is working at 5V, specially at higher clock rates. I would go for the first option like everyone else.Remember to use an op-amp that goes to ground, like the LM324. The problem with this aproach is the offset voltage and the variation on the gain due to the tolerance on resistors. Offset dominates the error at the lower part of the ADC range while the gain tolerance dominates at the higher end.Use what ends being cheaper and/or better suited for your task. If you have to use a $3 low offset voltage op-amp and $0.10 resistors that cannot be used anywhere else in your design, well, maybe it's best to use a $0.40 level converter and a $1 op-amp.I suspect you are using an ATX power supply.

author: ondreji
author_rank: Contributor
timestamp: February 09, 2012, 07:32:37 am
content: Good points, everybody! I'll go for 3.3V. Analog performance is not critical at all. Output actuator needs 1V at least and system has feed back loop. I need better resolution than better accuracy hence 12bit cheap DAC. Yes, I use ATX power supply.
how to get 10mA to 160mA - Page 1
Forum section: electronics / beginners

author: ascot
author_rank: Contributor
timestamp: January 27, 2021, 11:03:00 am
content: anybody know which transistor will boost 10mA up to 160mA

author: gnuarm
author_rank: Super Contributor
timestamp: January 27, 2021, 11:06:28 am
content: Quote from: ascot on January 27, 2021, 11:03:00 amThis is one of those questions that begs for more information on what you are trying to do. Asking which transistor can boost current is a question would seem to indicate too little information is available. To give a reasonable answer requires knowing the context of the question. Tell us just what you are trying to do in detail.

author: ascot
author_rank: Contributor
timestamp: January 27, 2021, 11:12:56 am
content: i've got a thermostat running at 12 volts 10mA ,at a certain temperature it turns on a fan but the fan needs 160mA hence the transistor

author: gnuarm
author_rank: Super Contributor
timestamp: January 27, 2021, 12:39:46 pm
content: Quote from: ascot on January 27, 2021, 11:12:56 amWhat power source is going to provide the 160 mA for the fan?When you say the thermostat is "running" at 10 mA, you mean that is the current it currently draws from the 12V power source? What is providing the 12V power? Can it provide an additional 160 mA for the fan?I do at least have an idea of what you are talking about now. The thermostat produces and output signal that is either 12V or 0V and can source or sink up to 10 mA, correct? If the power source can provide the 160 mA pretty much any transistor can provide the gain of 16 to control this fan. You can use a 2N7002 as a low side switch. You might want to connect a diode across the fan to deal with inductive kick back when the fan turns off.Is this what you are trying to describe?

author: alsetalokin4017
author_rank: Super Contributor
timestamp: January 28, 2021, 06:31:06 pm
content: pretty much anyThat was what I was gonna say too. But I'd use a mosfet like IRF3205 in a low side switch circuit. Just because I have a bunch of them and they have lower Rdss than the 2n700x type.

author: Terry Bites
author_rank: Super Contributor
timestamp: January 29, 2021, 12:38:00 pm
content: Reading you posts suggest you do not understand enough to be let loose near mains electricity- spend some time learning very basic circuit theory and terminology from a book.

author: Grandchuck
author_rank: Super Contributor
timestamp: January 29, 2021, 05:40:55 pm
content: This triggers on 5 mAhttps://www.amazon.com/ANMBEST-Optocoupler-Trigger-Expansion-Raspberry/dp/B08PNHHC65/ref=sr_1_12_sspa?dchild=1&keywords=12v+relay&qid=1611941833&sr=8-12-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzVkRSWVFZVFI3TUlUJmVuY3J5cHRlZElkPUEwMzE5MTQ4Mlo2VzZYM1BUSTRHSCZlbmNyeXB0ZWRBZElkPUExMDMxMzAwMUZERjFNVVVJM05VTiZ3aWRnZXROYW1lPXNwX210ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
how to get a waveform to show up on a screen? - Page 1
Forum section: electronics / beginners

author: Dmeads
author_rank: Regular Contributor
timestamp: May 11, 2019, 07:40:07 am
content: Hey!I am trying to build a heart rate monitor, and I want to be able to see the output waveform on a little lcd or OLED screen.Does anyone know how to do this? Is there like a mini oscilloscope that does this? the signal isn't that large like 7 volts probably, so I wouldnt need a giant screen.Also are the screens high input impedence?

author: radiolistener
author_rank: Super Contributor
timestamp: May 11, 2019, 11:26:22 am
content: 7 V is a bit large for direct ADC input. So, you're need simple voltage divider before ADC input. Also it needs to add analog bandbass filter, to eliminate high frequency noises and pulses. Then you're need to capture ADC output at fixed sample rate and record it into memory. Then render it into video memory of LCD controller.I think you will need memory for at least 10-30 seconds. Most likely 3-10 kHz sample rate will be enough for you to capture all details. With 10 kHz and 30 sec, you will need memory buffer for about 300 kilosamples.Here is some application note, which may be useful to get started:https://www.nxp.com/docs/en/application-note/AN4059.pdf?&amp%3Btid=AMdlDR

author: Dmeads
author_rank: Regular Contributor
timestamp: May 13, 2019, 10:09:53 pm
content: thanks!!!
How to get documents of devices - Page 1
Forum section: electronics / beginners

author: antercreeper
author_rank: Contributor
timestamp: April 20, 2024, 06:22:25 am
content: I am looking for devices to convert RGB(YCrCb) Parallel(or called MIPI DPI) to DisplayPort, and stream over Type-C.(DISTRIBUTION TO NON-MEMBERS IS PROHIBITED, however I have got a leaked spec, and there are some reverse engineer works over it...)https://github.com/gigaj0ule/arduino_fusb302_dp_alt_modehttps://github.com/CRImier/AltmodeFriendhttp://cybuild.blogspot.com/for example Toshiba TC358867XBG, Analogix ANX9807, etc...Luckily, DisplayPort old version can be open access(up to 4K 30fps), but need plenty of works.However, The biggest problem is to get the documents(sent email, but no reply :'( ), as plenty of devices's datasheet(as well as development package, have some excel table to calculate the clock and other register) are not published(sometimes you can get some leaked one). For no reason, they just don't give to you and refuse to respone.The saddest things while you want anything new or novel(always proprietary)(on the contrast, etc. Analogue VGA)you need to battle with them(It's not about how much money), ex. MIPI series(DSI, CSI, etc...), I only found IMX219 leaked datasheet, no more high-end HD cameras(for example, the Raspberrypi New Camera).1. First you need pay extra money for LVDS(or something serial) if you want to make ASICs.)(Of course DPI is much simpler, and you can get IP from cadence or some else to done these converting if you really need)2. However maybe I will choose this plan finally if there is no way, output HDMI(in fact DVI) or LVDS output and convert to DisplayPort.
How to get numerical results  out of LTspice - Page 1
Forum section: electronics / beginners

author: ocset
author_rank: Super Contributor
timestamp: July 28, 2019, 07:31:44 pm
content: Hi ,Supposing i want to get the power dissipated in a fet (or say the sum of power dissipated in two fets) to be spat out into the error log file (or wherever) after a ltspice transient analysis sim has been run...do you know how i do that?Eg in the attached, how do i get it to automatically spit out the result ofV(N016)*I(R1) + V(N017)*I(R2)..eg spit it out into a log file or whatever

author: bson
author_rank: Unknown
timestamp: July 30, 2019, 05:51:42 am
content: LTspice doesn't seem to have .echo or .print, but it does seem to have .meas, so it should be possible to add a ".meas V(N016)*I(R1)+V(N017)*I(R2)" directive somewhere following your .tran and find the results in the log. (cmd-L on mac) The result is a vector, probably of some trivial size for a transient analysis (I'm guessing).

author: macboy
author_rank: Super Contributor
timestamp: July 30, 2019, 08:14:51 pm
content: Power is measured at a point in time, so it is best to plot the values you are interested in an analyze the plot.Alt-Click (left click) on a component to plot its power. The, in the plot plane, you can Ctl-Click the name of the trace ("V(N016)*I(R1)" or whatever) to get the Average, Integral, and other things. You can also right-click to edit the expression, so that you can, for example, combine power dissipation of two components together in a single plot.You can also the .MEASURE to do powerful things. Look up the help. A simple example is:.measure TotalFetPower AVG V(N016)*I(R1)+V(N017)*I(R2).measure TotalPeakFetPower MAX V(N016)*I(R1)+V(N017)*I(R2)

author: iMo
author_rank: Super Contributor
timestamp: July 30, 2019, 09:54:44 pm
content: For example

author: Ian.M
author_rank: Super Contributor
timestamp: July 30, 2019, 11:28:50 pm
content: You can do all sorts of stuff with .measure. e.g:Code:.measure tran period10 trig V(vlc)=0 rise=1 targ V(vlc)=0 rise=11.measure tran frequency param 1/period10measures the time between the first and eleventh rising edge zero crossing of a signal named 'vlc' (i.e. ten whole cycles), then computes its frequency.N.B. if you don't want the nodes you are plotting or using for .measure to 'hop' aroundwhen you make a very small change to your circuit, name *EACH* and *EVERY* node you want to plot or measure.The key to success with .measure is RTFM and experimentation with a simple test circuit!However, especially when dealing with power dissipated, it can be helpful to low pass filter the instantaneous value of the expression one wants to plot or measure, before attempting to plot it or take measurements off it. This is quite difficult to do using waveform maths and its often more convenient to create a behavioural voltage source on the schematic to perform the calculation, then put it through a RC filter with an appropriate time constant and a named output node for convenient plotting or measurement.
how to get rid of the contaminating PWM signal - Page 1
Forum section: electronics / beginners

author: foxjuly
author_rank: Newbie
timestamp: December 07, 2017, 06:37:22 am
content: Hey Guys, I am currently working on a project of using arduino to control the computer fan. I used the Time1 library of Arduino to generate a 25 kHz PWM signal. The fan works pretty well and its speed can be controlled if I adjust the duty cycle of the PWM signal.Also, I want to measure the rotation signal from the computer fan. However, what I got is a signal contaminated with the PWM signal, So, how can I solve it ? Attached is the circuit map.Thanks a lot!

author: eblc1388
author_rank: Frequent Contributor
timestamp: December 07, 2017, 07:54:44 am
content: You cannot get rid of the PWM pulses, unless you stopped the PWM process.Your question is a common one and Mr. Giorgos Lazaridis had figured out a way to tackle that. Basically he just stretches one PWM pulse to 100% and measure the speed feedback signal. Then the PWM pulses returns to normal. He called it the "Pulse Stretch method". You can learn how he did it at the following link:PWM 3-Wires Fan Controller with RPM feedback

author: foxjuly
author_rank: Newbie
timestamp: December 08, 2017, 12:09:44 am
content: Thanks, I tried to use a capacitor and it works, I am planning to use a small coil in combination with the capacitor to see if it can further remove the 25 kHz PWM Signal.
How to get rotor flux from Back-EMF constant in a PMSM ? - Page 1
Forum section: electronics / beginners

author: cadena
author_rank: Contributor
timestamp: April 16, 2020, 08:31:16 pm
content: Hi everyone,Does anyone know how to do this and paste a link or name of legit, academic, source ? I only know the back-EMF constant from my motor but I need the rotor flux. Please any help would be greatly appreciated.

author: Vovk_Z
author_rank: Super Contributor
timestamp: April 16, 2020, 08:54:10 pm
content: Look here.

author: cadena
author_rank: Contributor
timestamp: April 16, 2020, 09:13:33 pm
content: Thanks a lot @Vovk_Z, I am actually using Simulink and I needed to know the equation to use for my Simlunik block and hadn't realised that the appropiate eq. is in the documentation.
How to get started in asynchronus design? - Page 1
Forum section: electronics / beginners

author: asgard20032
author_rank: Regular Contributor
timestamp: October 11, 2016, 04:04:02 pm
content: I want to start experimenting in the asynchronous design field, but how to get started? Is there any simulator, FPGA like device to experiment?My ultimate goal would be to design a 4 bit or 8 bit cpu asynchronous, just for the fun of doing it and learning.

author: rstofer
author_rank: Super Contributor
timestamp: October 11, 2016, 04:08:10 pm
content: You can model combinatorial logic in a CPLD or FPGA. What you probably can't do is make sequential circuits operate asynchronously. I would think that state machines are out of the question. I know a fellow who tried to reinvent a CPU using asynchronous logic but he ultimately failed. In the old days of transistor logic, gate delays were long and easier to deal with. A lot of timing was done with wire length.An ALU, itself, is a combinatorial block, no problems with it being asynchronous. Registering the output is a different matter.

author: Dave
author_rank: Super Contributor
timestamp: October 11, 2016, 06:44:42 pm
content: You could download something like Xilinx ISE/Vivado or Altera Quartus and just use their simulators. You can then always shove your designs into actual FPGAs at a later time.
How to get total power from spectrum measure of a signal - Page 1
Forum section: electronics / beginners

author: bonzer
author_rank: Regular Contributor
timestamp: January 27, 2019, 10:27:40 pm
content: Hi everyone! Please help me to understand how exactly to get the total power of a signal for example that from this figure from aspectrum analyzer.Forget about that narrow band signal for now andconsider only M2 part.I think I would need to sum all these values through the band. I need the power spectrum density (PSD).What would it be? The values I see are RMS (right?). Then the PSD in this case would be (as for sinusoids) the power of two of these values (converted in linear scale).Then should I multiply the almost constant PSD by the band? (assuming I know that there are for example 100Mhz of -3dB band).Is total power PSD*Band ?
How to get wake on lan to work on lattepanda? - Page 1
Forum section: electronics / beginners

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 02, 2017, 09:39:25 pm
content: HiDoes anyone know how to use WOL on the lattepanda?I have enabled it in the device manger and disabled windows fastboot but nothing happens.Any ideas?Thanks in advance.

author: Kohanbash
author_rank: Regular Contributor
timestamp: March 03, 2017, 03:46:17 am
content: Did you check the BIOS to make sure it is enabled?

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 03, 2017, 06:44:13 am
content: Quote from: Kohanbash on March 03, 2017, 03:46:17 amI had a look in there but I could not see anything.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: March 03, 2017, 06:48:00 am
content: Depends on the NIC capabilities also IFRC. If the NIC can't do it, you're out of luck.

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 03, 2017, 07:01:20 am
content: Quote from: Ed.Kloonk on March 03, 2017, 06:48:00 amWhats IFRC? International Federation of Red Cross and Red Crescent Societies? The NIC show WOL as enabled in the device manager but its on the USB bus rather than pci.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: March 03, 2017, 09:07:12 am
content: Quote from: abdullahseba on March 03, 2017, 07:01:20 amSorry. That's my autocorrect helping me say IIRC If I Recall Correctly.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: March 03, 2017, 09:09:53 am
content: Gotta ask. How come you haven't asked the lattepanda community forum?

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 03, 2017, 09:25:04 am
content: Quote from: Ed.Kloonk on March 03, 2017, 09:07:12 amloooool

author: abdullahseba
author_rank: Frequent Contributor
timestamp: March 03, 2017, 09:27:29 am
content: Quote from: Ed.Kloonk on March 03, 2017, 09:09:53 amI tried to crate an account and all it asked for was an email and a username, so when I got to the login page I had no password and there was none in the email they sent.password recovery was useless.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: March 03, 2017, 09:32:23 am
content: Quote from: abdullahseba on March 03, 2017, 09:27:29 amYeah.R U Human?Sucks.
How to ground: power supply (-) connect to ground - Page 1
Forum section: electronics / beginners

author: frowin
author_rank: Newbie
timestamp: February 25, 2020, 03:49:37 pm
content: Hi together,I have a general question about grounds. I have a curcuit and all parts share one ground. It includes a 24V DC power supply and I connected (-) to ground. I also connected the ground of the signal inputs to this shared ground. Could this be dangerous for the signal path?In principle the question is more general. When can one share a ground for everything? Or should one separate grounds of the circuit from the "input signals"?I'm just afraid of destroying the machine which sends signals to the circuit. It also feels weird to connect a 24V DC powersupply to the same ground as the signal inputs.Thanks in advance for your comments!

author: ogden
author_rank: Super Contributor
timestamp: February 25, 2020, 04:14:38 pm
content: Connect all "grounds" together in one place (star topology ground) and you will be fine.
How to hook up an oscilloscope to a stepper motor driver? - Page 1
Forum section: electronics / beginners

author: cvriv
author_rank: Frequent Contributor
timestamp: May 09, 2017, 05:15:31 pm
content: I have this 3D printer that I assembled and the z-axis refuses to move. I know the steppers are good. I think it's the mainboard. I want to hook up the oscilloscope to see what the z-axis pins on the board are doing, but first want to hook up the oscilloscope to the y-axis pins because the y-axis works fine. I want to know what a working axis looks like first.They are four wire steppers and I know that red and blue(A and A') is one coil and green and black(B and B') is another coil. I hooked the osc from ground to the red pin. When I try and move the y stepper, I get some activity on the oscilloscope but can't good a good visual of the waveform. If I try to scale it just disappears off screen and can only get it back if I hit the auto button.I'm doing a lot wrong here. Can someone please advise? Thanks.Do I hook the osc up to red and blue? I somehow think that's not a good idea. I dont know.

author: james_s
author_rank: Super Contributor
timestamp: May 09, 2017, 06:28:08 pm
content: Four wire motors are driven by a pair of H-bridges, look up the datasheet for the driver ICs being used. You can scope any one of the four wires relative to ground and you should see something however stepper motors are inductive and there is also magnetic coupling between the windings so you're likely to see a whole lot of noise and ringing. Better may be to look at the signals going *in* to the drive ICs and check the power rails. If the signals going in look good, the ICs have power, and there is not an open circuit between the IC and the motor and the motor is not running then the IC is likely bad.

author: rstofer
author_rank: Super Contributor
timestamp: May 09, 2017, 07:22:36 pm
content: You can set up your scope to do A-B or differential measurements. Be sure to remove both ground clips so they aren't dangling where they shouldn't be and to prevent an operator induced 'oopsie'.You will get a trace going both above and below the 0V line as the polarity of the winding changes.
How to hook up an RF Line amplifier? - Page 1
Forum section: electronics / beginners

author: Deactivated-1
author_rank: Frequent Contributor
timestamp: April 14, 2021, 10:42:53 pm
content: I got this TV Line Amplifier for some reason, and don't have any use for it, so I thought of experimenting with it with audio, it says there that it only goes from 47MHz which is miles over audio, but I'll hope that it was an error on the sticker and they mean 47HzAlso it could just have a high pass filter inside which I could bypass perhaps...but I have no clue how it's supposed to get the 12V (it seems) power? do I just connect like a 1k resistor to 12V from the output, and then get my signal trough a coupling capacitor?[ Attachment Invalid Or Does Not Exist ]

author: Tony_G
author_rank: Super Contributor
timestamp: April 15, 2021, 04:32:43 am
content: No idea if it works at all down to that but the bottom of the VHF TV range is starts around 47 MHz and the UHF TV range extends up to 890 MHz or so (this is fairly country dependent I believe) so I think the labeling is correct.Good luck with the experiments.TonyG

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 15, 2021, 04:55:21 am
content: You're looking for, drumroll... a bias tee.Basically, little more than an inductor from DC to line, and a series cap to block DC going out to the receiver. Evidently you'd want somewhat more than 75R / (2 pi 47MHz) = 0.25uH, and the capacitor can be way bigger than needed, ceramic chip caps are no problem here.High frequency response depends on quality of both components. The capacitor can be laid out in a microstrip transmission line of the same dimension, that'll automatically be good to many GHz.The inductor may have impedance dips due to internal resonances, particularly if it's a complicated winding (as you'd have for an oversized value), so there is some wisdom in using only what you need, not going gonzo. Shop for one with impedance curves and verify it's free of dips in the range. (The first (parallel) resonance is fine, by the way. Peaks are good. What matters is impedance dips.)Also it needs to be rated for whatever current draw the line amp needs, including saturation current if it's a cored inductor.Tim

author: David Hess
author_rank: Super Contributor
timestamp: April 16, 2021, 02:37:50 am
content: A resistor will work in place of the inductor for the bias-t with some loss of gain.
How to I read and edit the serial EEPROM ST 14771 - Page 1
Forum section: electronics / beginners

author: oelarse
author_rank: Newbie
timestamp: March 26, 2017, 04:49:46 pm
content: Hello .I have tried to read the content of this EEPROM using the EZP2010 but it is not able to read this old EEPROM.Is there there any affordable programmer with software which is able read this chip ?thanks
How to identify a zener plus ptp wiring. - Page 1
Forum section: electronics / beginners

author: Hextejas
author_rank: Frequent Contributor
timestamp: January 17, 2018, 11:56:58 pm
content: When I am doing some breadboarding and am finished, there are usually 1 or 2 zener diodes that I have used.Question is how the heck do I identify them so I can refile them ? They are so tiny. I have been throwing them away. 😂Next is that I would like to try my hand at doing some ptp wiring. I am not eager to start making my own pcb yet, so this seems like a fair compromise. Are there any kits that do this ? I th8nk that I need some kind of a wire wrap tool ( I have one ), plus some size of wire ( I have some 22awg ), a blank pcb with holes in it, and I guess some headers ?Did I miss anything ?Thanks

author: Benta
author_rank: Super Contributor
timestamp: January 18, 2018, 12:38:10 am
content: OK, I'll bite.What's "ptp wiring"? Google returns gibberish.Perhaps a well-phrased question would give more answers?

author: jaycee
author_rank: Regular Contributor
timestamp: January 18, 2018, 12:57:29 am
content: point to point wiring

author: Benta
author_rank: Super Contributor
timestamp: January 18, 2018, 01:06:08 am
content: Quote from: jaycee on January 18, 2018, 12:57:29 amMakes very little sense in the context of the original question...

author: james_s
author_rank: Super Contributor
timestamp: January 18, 2018, 01:21:24 am
content: I use a resistor, power source and a multimeter to identify zeners. Just take a resistor of say 1k-20k, value is really not critical and connect it in series with the zener, then connect that to a DC source that is higher than the highest voltage zener you want to measure. Put the meter across the zener and you will have the value.

author: Hextejas
author_rank: Frequent Contributor
timestamp: January 18, 2018, 04:32:04 am
content: Well I hope that is clearer. 2 completely different topics.I hope that its permitted.

author: james_s
author_rank: Super Contributor
timestamp: January 18, 2018, 06:39:20 pm
content: Permitted yes, but not really recommended. You are more likely to get good replies by posting separate questions unless they are very closely related.

author: lordvader88
author_rank: Frequent Contributor
timestamp: January 18, 2018, 07:30:45 pm
content: I know that common zeners like a 6.3V 1N4735 ? or whatever, they are 1/2W and need about 44mA going through them to hit the 6.3V (or whatever it is). They are probably bigger then what u said.1N4728A to 1N4764Ahttps://www.vishay.com/docs/85816/1n4728a.pdfThat lists all the currents needed for them. 1/2W is sort of big, they get warm/hot.I'd say just hook them up with a variable resistor and measure the voltage and/or current. I guess the I vs V levels off to flat line.
How to identify Kynar (PVDF) insulation? - Page 1
Forum section: electronics / beginners

author: e100
author_rank: Frequent Contributor
timestamp: January 11, 2017, 06:44:55 am
content: I bought some cheap wire wrap wire which claims to be PVDF insulated.The insulation is easily damaged and can be stripped just using fingernail pressure and turns white if you stress it.If real PVDF slippery like PTFE and difficult to strip?