The circuit diagram for your 250w to 5000w PWM DC/AC 220V Power Invertor is not very legible.Can you e-mail me a better copy?

Posted by AkhbarB 1 year ago

How to eliminate PWM noise at slow speeds when using a PC fan? Answered

My power supply has a cooling fan inside. I wanted to slow it down to reduce the fan noise. When i use this circuit in the picture the PWM works great except for the low speed buzzing. Turns the fan into a speaker. Is there some way to eliminate the buzzing?

Asked by WWC 5 years ago

I need a simple way to generate a PWM signal?

Alright, so I took apart an old RC helicopter with a spy cam in it, and noticed it has 3 wires, just like a servo, so I modified an arduino script to keep a servo on all the time, and voila, the camera entered recording mode, now, I have an idea for something to do with this. I want to make a projectile for my air canon to fire the camera from, I think it might look pretty neat, however, I need a small simple circuit to make a PWM signal, and one that is constant enough to keep it recording constantly. I've seen some 555 timer ones but they fluctuate apparently, and I think that might turn the camera off then on.

Asked by XOIIO 5 years ago

What is the advantage of PWM vs supplying variable voltage?

Friend and I are very new to electronics and we were dimming LEDs in completely different ways I think. We both defended the way we had learned to do it without really knowing why :) Any thoughts? Also, with a servo, can you do both methods as well? And is there a way to tell a servo to go to a specific "spot" on its turning radius, or is it all relative, like supply a low voltage and it will turn a little? Do you just sort of calibrate it, so you can figure out how much voltage at how much time goes a constant radial turn? Blah

Asked by prismspecs 5 years ago



Asked by ER. ARJUN SHARMA 6 years ago

PWM to MPPT solar Charge Controller

I have an Hybrid Solar Inverter with 50A PWM solar charge controller inbuilt into it. It works on 24V battery bank. I am having 800Watt of PV module installed in the system. As my inverter is having PWM charge controller, I am not able to harvest maximum of power from panels. I want to know that, is there any arrangement or device which can be put in between PV panel and my Inverter which can increase efficiency or can act as PWM to MPPT converter for my Inverter? My Solar Pannels generates often 39V but I couldnt utilize the surplus power as it stepped down to 24 Volt.

Posted by Shashi BhushanS 3 years ago

Reading the max voltage of a low duty cycle PWM?

How do I measure the maximum voltage reached by a very low duty cycle PWM signal without having to alter the signal. The multimeter shows no reading or gives a very brief wrong reading and falls back to zero. I don't have an oscilloscope. Are there any other alternative set-ups to measure just the voltage in this case. Please suggest.

Asked by raftor 2 years ago

PWM fade

I am using micro controller in a project that has a set of functions (API) that can be used for a plethora of things.. (just up to you to program it that way) LOLIt has a PWM control... which i am trying to use to FADE in (and out eventually) a high powered LED (LUX III to be specific).. the problem I having is that at a certain point (say at 50-60%) of full brightness I see a VISUAL jump in brightness.. Im trying to get it to be smooth the whole way through to 100%more or less the code is like:PWM = PWM+2which I then wait 10 mSecs and loop it again...I have tried to put in some conditional checking to check to see if the current level of PWM is at a certain threshold..and then only loop it again after a longer delay (say 300mSecs) or something..I tried to search.. ut Im not sure on how to get a CONSISTANTLY smooth fade...ot smooth to say 50-60%..then a visual jump in brightness and then smooth to 100%..any ideas or links on the subject are appreciated.Thanks

Posted by xl97 9 years ago

Can you take the arduino chip out of the arduino?

I have a pulse width modulation circuit set up on my arduino. Is there a way to take the chip out and connect it to leds? Can anyone explain this simple concept to me? I need to have a TINY PWM circuit

Asked by SpiffyChee 7 years ago

How to use pc817 and tip122 to control rectified mains LED array?

I have 3sets of leds that conduct at 250v so I wanted to use my 100v TIP122 NPN(with TVS diodes to protect it from over voltage) and PC817 opto-isolator to PWM the LEDs which are common cathode, is there a way? Thank you all for all the superb suggestoins!

Asked by yagoa 10 months ago

How do I use an Arduino to write say 2.1 volts? Hobo dataloggers accept 0-2.5vdc inputs. Arduino outputs PWM.. thanks!? Answered

I'm working with a university and they love their Hobo's and I don't blame them... they're pretty straight forward to use...  I'd like to write to the Hobo... here's the hobo analog inputs: 0 to 2.5 Vdc; 0 to 5 Vdc; 0 to 10 Vdc; 4-20 mA Hobo stats: Analog channels: 0 to 2.5 Vdc; 0 to 5 Vdc; 0 to 10 Vdc; 4-20 mA Accuracy (logger only): ± 2 mV ± 2.5% of absolute reading; ± 2 mV ± 1% of reading for logger-powered sensors Resolution: 0.6 mV Sample Rate: 1 second to 18 hours, user selectable Time accuracy: ± 1 minute per month at 25°C (77°F), see Plot A Operating range: -20 to 70°C (-4° to 158°F) Operating temperature: Logging: -20° to 70°C (-4° to 158°F) Launch/readout: 0° to 50°C (32° to 122°F), per USB specification Humidity range: 0 to 95% RH, non-condensing

Asked by hydronics 5 years ago

Help with PWM dimmer?

Ello mates,so i biult a pwm dimmer acording to but its kinda different,i used irf530n and ne555p ic, And when i connected all of the components with a 12v source it happens nothing except that little spark comes on gnd with adapter? Help please ? 

Asked by JohnSmith-Workshop 1 year ago

Control Logic with PWM? Answered

I am currently working on a robotics project, and need a bit of help. I have this H bridge, and would need to control it via PWM. Speed control isn't necessarily what i need, though i wouldn't mind. (In4 i should have just bought an ESC) The whole bot is controlled by PWM (All servos) except for the two DC motors that i have on it -- One for forward and backward, and another for rotating an arm. How would i control the H Bridge with PWM? Which pins would i connect what to? 

Asked by RocketPenguin 3 years ago

double multicopter flight controller? Answered

I wanted to know if there are any flight controllers that have separate sensors. I want to use 2 either quad, hex or octo flight controllers with one setup as + and one setup as X to make an octocopter, duodecacopter or hexadecacopter ( 8, 12 and 16 blades respectively ). I want to have a a 6 or 9 DOF IMU connected to 2 separate controllers for larger multicopters. Either that or would anyone know how one might go about designing an arduino controller using either a pwm shield or a TLC5940. Thanks in advance

Asked by monty324 4 years ago


I have dismantled a CRT monitor and I was wondering what I should with a UC3842B (HIGH PERFORMANCE CURRENT MODE PWM CONTROLLER) that was on the mains power side of the PCB.Here's a link to the datasheet for it.Any suggestions on what I should use it for and how to wire it up?

Posted by thermoelectric 9 years ago

Controlling the speed of a 12/24V 100W DC motor? Answered

Hi all, I have been given a 24v DC 100W old scooter motor and one 12v battery (the other 12v battery died). I'd like to be able to control the speed of the motor and have been told I would need a PWM. I have found a PWM on ebay which says that it's a PWM HHO RC Controller, 12V 30A. Would this one be sufficient to slow the motor to say 10-20 RPM and back up to full speed? Thanks in advance.

Asked by dchurch24 7 years ago

Transistors, connecting them in paralell. Will they act as one transistor to use them for higher amp? Answered

I want to build a PWM but am having trouble finding transistors powerful enough. Will they act as one if I connect them in paralell?

Asked by omnibot 9 years ago

PWM with timer on a 12v constant voltage power supply? Answered

I have 5 - 12v LEDs running in parallel. Each lamp has it's own heat sink, fan and resistor,. Each one steadily uses about 850ma. I'm hoping to add a timer of sorts, something that adjusts the light level on a schedule. I've read about people using something like a 555 and/or the Arduino, but I'm kinda lost. Any pointers?

Asked by lford4 6 years ago

Controlling a motor with PWM

I'm building an ROV for the MATE ROV competition with a high school team this year.  For this year's competition, we've decided to control our bot via an Arduino Mega, and we're using PWM to potentiate the thrusters.  As the person designated to electrical, I fortuitously have no idea how to set up an intermediate step from the Arduino to our thrusters.  I've looked into H-Bridges with both Relays and Transistors, and defaulted to the transistor. How would I choose what transistor to use though? I've tried several (all BJTs) and they're giving me nothing but problems.  Should I switch to a FET? Should I use a P type and an N type, or only one?  What specs should I purchase them with?  Do I ask too many questions? Help!  (I'm trying to control a 12V 6A motor with a 5V Pwm signal. Thanks!)

Asked by unununium 7 years ago

Using arduino for Serial in/PWM control

Hello I am wondering if there is someone who can help out a super beginner.  I need to write a code that will allow me to type send a serial message to the micro (im using an arduino uno) to be able to set PWM port to a certain percentage thus changing the fade of an led. I would also like the program to echo back to me a text string indicating what has been done. Is there anyone who can help?

Posted by JonH23 2 years ago

DIY Design PWM Contoller for 3 HP 36VDC Motor

A friend of mine and myself want to build a couple of small electric utility vehicles to use for chores around my farm and his cabin. We are thinking of something along the lines of the eMule.  We just bought 2 new 3HP 36VDC motors for a really great price off of eBay.  See pics. I want to build some PWM controllers for these to help keep the price of the project down and because I like building things. I could use some help though on a few things. How many amps should the controller be rated for? 100 amps? Larger? Are there any designs out there for a DIYer like me? Thanks.

Posted by starguywisc 4 years ago

can I use a wall dimmer switch to control the heat of my soldering iron

or a strip heater for bending plastic made from about 12 inches of heater element from an old toaster or hair dyer? do they use PWM,or just a big variable resitor?

Asked by z28racer 9 years ago

I give up. Does anyone have a data sheet or manual for an electrocraft MAX-100 PWM drive? Answered

This is no longer supported by electrocraft.  I got it out of an old automated TIG welding positioner.  If anyone knows anything about this particular one I'd be eternally grateful if you would share it with me.

Asked by AngryGuy70 6 years ago

rc project

I decided to go for the rc car. I'm using the 1/5 scale  maxstone trying to combine it with the raspberry pi. I'm also using adafruit's pwm. I know this might be old to others but it is new to me. I am a beginner and I am very excited about it!    I am open to any suggestions, comments, feedback, links, anything would be great!

Posted by SMILEY4242 8 months ago

PWM control and "off" for arduino IR remote?

I've built a simple IR remote to trigger a led bar using... As my template.  All the leds turn on a-okay but I'd like to be able to implement both an "off" function using the same button  ie. button1=High       leave on for desired period of time... button1=Low I'd like to be able to use a no delay fade in/out as well... ie. button7= All leds fade in/out until button7=low (using the method above^^) I've tried plugging in various other parts of code to no avail... Any help would be greatly appreciated!!! Thanks!

Asked by vtrguy 4 years ago

I need to know where to put the POT in the treadmill motor controller?

 I need to know where to put the POT in the treadmill motor controller? Because I have a digital controller from model MC2100 (proform 400X) Thanks

Asked by dulo 8 years ago

Capacitor charger? Answered

Ok so im planning on building a portable coil/rail gun. But one issue is I cant quite find a circuit that would work best to drive a custom transformer. The charger I have now is a flyback driver that I used a wall adapter to power. I just need some advice and maybe schematics. Thanks, bud

Asked by budhaztm 5 years ago

Electronics Help

Hi ppl,I am currently making a variation on this circuit: understand how it all works but do not understand the principle of the inductor capacitor used (bottom left), if anyone could give a brief explanation of this (links are good too) and also some formulae i would b e very greatful!!thanks

Posted by drummer ian 10 years ago

How to connect 555 signal generator to Tesla coil or other High voltage application

Hi all, I hope everyone is well. I have 2 circuits here and was wondering if someone would show me how to connected them, it is probably very simple, but I just want to be sure. here are the 2 schematics I'll be working with... I assume I just use a common ground... but we all not what assuming makes us :)  Thanks all in advance, 

Posted by dalmond1 6 years ago

Is the led driver malfunctioning? or am I?

The led driver Im using an arduino to fade LEDs through PWM. The code works on normal rgb LEDs, but i need it to be much brighter. I bought 3, 3 watt, HPLEDs. they are very very nice and bright. but only work with all colors full brightness... i have attached the arduino pins that controlled the normal rgb LEDs to the driver. but this does nothing different then if the pins were disconnected. also if i dont power up the driver and just plug in the arduino it will change the colors of the leds. but it will be just as bright as the normal ones because its only getting 5 volts instead of 13.5. also the color fade cycle acts really weird. not sure what thats all about or why it even does anything just with the arduino plugged in. Does anyone know where to get a decent LED driver? i have looked around for days and could not find what im looking for. this looked like my best option but its not working... thanks for your help. -Rex 

Asked by RexHex 5 years ago

Using a hall effect sensor with TL494 pulse width modulator.

I have an electric billy cart with a dead controller board. I constructed the kit circuit below to replace the dead board and it works well enough for the job except for one small problem. The throttle on the billy cart utilizes a hall effect device and not a pot. The billy cart also has a handbrake with a switch that closes when applied. I use this with a resistor to discharge C2 and pull pin 4 (inhibit) high. This ensures a gentle start (as the capacitor slowly charges through the 100k resistor) if the brake is released with the throttle advanced. The output range of the throttle is 950 mV to 4.1 V if VREF (5V) is used as the supply. (I'm dropping it in in place of the pot.) 4.1 V is sufficient to achieve the maximum 90% duty cycle of the chip, but 950 mV leaves me with a minimum duty cycle of about 21%, and of course a motor that won't stop. Will changing the divider ratios 20k/2k2 & 47k/47k be sufficient to get me zero speed or am I going to have to do something more exotic? Thanks in advance.

Posted by Rasputin182 10 years ago

Does anyone know any good PWM tutorials for the AtMega32 and AtMega168 chips. These are not arduinos. Answered

Does anyone know any good PWM tutorials for the AtMega32 and AtMega168 chips. These are not arduinos. I am looking specifically for servo and DC Motor control but any tutorial on PWM should give me the base I need to move forward.

Asked by TheTrustedOne 9 years ago

Is it possible to use PWM on Arduino to control the voltage of an external power source? Answered

Let's say I want to vary the speed of the motor that operates at 12V. Since PWM on Arduino only provides the maximum current of 5V it can't power the motor sufficiently. So my question is how can I use PWM on Arduino to increase or decrease the input voltage of the external source? I will appreciate your answers.

Asked by Shizen 1 year ago

Arduino PWM and RGB LED strips

Hi.  So I bought an arduino uno, some IRL530NBPF, and 4,3m RGB LED strips. I want to control the strip with the arduino, but can anyone tell me how to hook it up?

Posted by sinding 7 years ago

Is it possible to use PWM to send data via a laser? Answered

I am looking into making a laser tag system with an arduino and was wondering how easy it would be to make a laser diode output PWM signals, instead of using an infrared LED. I'm sure this has been considered before, but I couldn't find it anywhere!! Obviously all players would be given protective glasses to wear :) (on a side note: I was also wondering that if it was possible, could it be used in an RGB laser, to make more than seven colours?) Thanks in advance :)

Asked by 5225jackiechanman 6 years ago

arduino control of digital potentiometer

Is it possible to use my new Ardy board to control a 1-wire potentiometer that will, in turn, control the pwm output for a high-power LED?The POT is here. The lights are REBELS @ 700mA.THe POT will be run in "non-parasitic" layout.

Posted by Tweac-it 9 years ago

Driving DC brushed motors with Pi/PWM/Arduino? Answered

I have a few motors (2) that i would need to be able to drive via a PWM input (Probably from pi/arduino). I have been looking at H bridges, and that seems to be my answer, however, I can't figure out which one i need... The motors are identical 9v ~2 amp stall current motors. I would need both directions for each, and would obviously be using an external power supply.  With that said, which H bridge would suite my needs, along with what type of setup? I only have abut 4-6 PWM pins left to use, if that helps.

Asked by RocketPenguin 3 years ago

Motor controlers?

I have a 24 volt motor from an old mobility scooter and I want to control it with my arduino but I have no idea what motor controller to use. I presume that I will need to use PWM to control it but what hardware to use I have no idea. Any help I would really appreciate. Thanks

Asked by cheesemarathon 5 years ago

Is feedback compulsory for a pmdc motor controller?

I am designing a controller circuit(pwm based) to control a 36V,12A pmdc motor to be used in an electric cycle.  As i won't have any load changing situation, is it essential to have a tachogenerator feedback or is it fine to just have a current limiting algorithm?  Please help me out , am stuck with this for a long time..

Asked by elec_freak 5 years ago

If I use 12v, the motor burns, 8v it takes longer to burn and 5v is not enough, will PWM save me? Answered

Here's the deal: I'm working on a project that uses 2 motors (PS2 controller vibrating motor, without the counterweight), I assume these are 5v dc motors, right? Both rotate the same axis (1 is not enough due to the pressure that is being put on it, a spring mechanism stuff) With 12v it runs like a dream, till they burn! and from what I observed, always 1 motor hits higher temperature than the other, is there a problem with that? Then I dropped it to 5v with diodes and the motors didnt have the strenght to start spinning, so I raised to 8v and they spin, not very smoothly (is that spell right?), but you know, they work, but still they're overheating! If I used PWM to control both of the motors, would it work and not burn'em? Thanks and sorry for the long and confusing text.

Asked by Kokkan 7 years ago

AVR sense/PWMing Help!

Hi again! I'm intent on finishing up a few loose end projects of mine, but before I do so, need the following information. How can I sense some resistance or voltage with my uC? I know I can do an a/d conversion, but that only triggers when Vin > some 1 preset value. I'm looking to make an adjustable knob to turn the intensity of an LED up and down. Also, how can I PWM some LEDs with my AVR uC - I can use the tiny2313 or mega8 or tiny 13, but I have no preference. I just need 3 different PWM channels. Any ideas? I already googled, but apparently I'm terrible at finding good tutorials. (oh, and I'm coding in C) The LEDs will be inserted into this nice, custom built (by myself) welded devil duckie. Horns and tail will turn to control RGB. Thanks a whole lot, -Muffin

Posted by T3h_Muffinator 10 years ago

Speed controller for brushless electric bike motor? Answered

I have obtained a 400W 24V 2800RPM Monophase BLDC motor with related power supply and a 24V 40A-rated pulse width modulator unit, however from what i understand the PWM won't give me full control (if any at all) of the actual speed of a BLDC motor. I want my motor's torque to remain relatively intact and for it to cover a range of about 50-300 RPM, with no need for exact control. Are my only choices to build a pulley mechanism or to buy a mechanical gearbox? I'd like to control my motor electronically.

Asked by Khalim 3 years ago

Noise in Amp from LED Strip & servo

Hi, I am working on a project in which TL072 is amplifying an audio signal which is going to speakers & arduino analog input. Amp is powered by a wall wart with 12V 2A output. The same 12V is also regulated to 5V and used to power an AVR. The AVR is being used to PWM, using a power transistor(TIP120), an LED strip taking 1A from the same 12V supply. There  1) Now the rapid switching of current for LED strip is messing up the amplifier output. It's working fine with LED Strip off but when using PWM, there is a high frequency noise in the amplifier output. I have a 0.1uF and 10uF caps near power inputs for both AVR and amplifier. This is probably due to insufficient decoupling. Can someone please help me make it better? 2) There is another independent source of noise I'm finding which I'm unable to explain. The audio is going into Arduino which is controlling a servo as well. As soon as the servo is connected, there is a constant loud noise in amplifier output. This remains even after powering the arduino and servo using seperate USB supply(only ground connected). I placed audio setup and servo data wire far apart since they may be interfering due to PWM used for servo, but it wasn't of any use. Since in both cases, amplifier is producing noise, I think my amplifier diagram might be at fault. If I remove the amplifier, the audio stream reaches arduino without any noise . Anybody got any ideas how to remove these 2 noises? Attached images: amplifier schematic, graph of audio input in Arduino analog pin. -Antzy

Posted by Antzy Carmasaic 4 years ago

Is it better to use a MOSFET with an Optocouple for PWM?

I want to control an LED strip from a microcontroller, ideally with parts I have on hand:- IRF740 MOSFET- PC123 Optocouple- ESP32 Microcontroller (Has 5V power regulator)- 12V LED strip (5m)A lot of the tutorials online seem to suggest that only a MOSFET are required (Except this one, which seems to me like a safer way of designing this, since I get to treat the 12V and 5V circuits as completely separate). I have a relatively limited knowledge of these things but it seems like sending the full current through the microcontroller on the ground side is a bad idea.Is it safe to run the LED strip's ground through the microcontroller? Are there any additional steps I should take to make sure I don't destroy my LEDs, MicroController, or anything else?

Asked by jonrb 8 days ago

Controlling the speed of a Delta fan via PWM? Answered

First off, i would like to state i am a beginner in this area of whatever this area may be considered to you (Not a complete beginner, i know one or two things...). With that being said, i may need things explained to me to a certain level of extent.  The way i learn is hands on, and having a goal. Since i want to learn the basics of Pulse Width Modulation, i started looking around for a project, and had found one after my brother, a person who works in the International part of Technology (IT Guy.) gave me a project to work on, The project being, to control a 12 volt,  4 amp, 48 watt delta fan and the speed it spins at. His reason being, "I have two delta fans that do a wonderful job at cooling my ridiculously overkill of a computer. My problem, is that the amount of noise they make is too loud, and i would like to be able to adjust the speed of them in order to reduce noise." Since his motherboard cannot control the speed of the fans, he is looking of a manual way of doing it, sticking some sort of device in between the ATX power supply, and the input for the fan(s). The fans have three cables: Red(Positive) Black(Negative) and Blue(With minimal research, i believe this is a censor for the CPU to know at what speed the fan is running at. I also heard it is used for speed control? Someone please clarify.) Looking into methods of reducing speed, adjusting the Pulse width looked like the best idea. Now, for my question. How would i make a device capable of controlling the PWM of such device listed above? I would like to adjust speed via a potentiometer. Thank you for your time and support, -RocketPenguin/Nicola Tesla/LinuxJunkie

Asked by RocketPenguin 4 years ago

Connect DC motor to Servo Output? Answered

I am currently working on a robot of sorts, and have a quick question i would like to ask. I am using a Raspberry Pi as my "Brain", and am using ServoBlaster as my software. I am currently working on driving 6 servos and two motors with said software. My question is, how would i attach the motors to the board? I would like to control the motors with the same software (ServoBlaster) and thus would like to have them run off of PWM. The software allows me to change the min and max range of width, along with a whole bunch of other things, but that is for a later date.  So, my question is, how would i wire a motor up to a PWM output? I would like the motor to be continuous rotation (I am using a Mindstorms motor for the task, which will move the robot). I guess i could use an ESC, but i would like to do it without one (Though, if you linked one that would work in this situation, I wouldn't kill you :P Here is a link to the motor if you need more info on it: )  Preferably a method that doesn't require purchasing something i don't have would be best. If this isn't possible, please keep it on the lower end of price tags, as my funding is running dry. Thanks!

Asked by RocketPenguin 3 years ago

Solar panel short reads 28v? yet charge controller reads 14v? Batteries?

I have a solar panel that I picked up on internet for free due to damaged glass(no biggie).  Placing a voltmeter across the output leads has 28.6volts.  I connected this to a PWM charge controller recycled from a junk yard.  I set the CC parameters to 24v and hooked up two 12v car batteries(13.2v good) in series to make my 24v circuit.  Now the CC digital panel reads 14v.  Checked all the connections and retested the panel, two batteries and CC. It checks out ok. But why does the CC readout at 14v in full sunlight? yet the panel reads 28.6v? The only thing is the two batteries are different in AH ratings. One is 96 Ah and the other 115Ah.

Asked by JuG2 1 year ago

Rotating a simple DC motor really slowly (1 rotation per 2 hours)?

This is to rotate a bike chain on a small cog. After doing some research, I came across a component called a Pulse Width Modulator. Would this be suitable for turning a simple DC motor at 1 rotation per 12 hours(EDIT: I meant 1 rotation per 2 hours, not 1 every 12 hours)? Or, would it only get me to a certain point before I need to use gear ratios to achieve my ideal revs? This really is a budget project so nothing too fancy.  Thanks

Asked by Nenagh 2 years ago

Small led driver?

I need a chip that will be able to power  5 or more LEDs not past like 10 though cause it's not necessary channels of LEDs ,I want to be able to have each channel doing different patterns at the same time, blinking ,fading ,or just on.  (it doesn't matter how much MA the chip can handle as I will be using transistors to amplify the signal ,most likely) It needs to be able to fit in a 1/2 inch tube. I think this one will work but im not sure. I think this will only work on printed PCBs if I can i'd rather have something i can wire up with ether perfboard or wires. 

Asked by the_burrito_master 6 years ago