pwm

I am trying to send PWM signals using STM32F100RBTx but it do not working. I double checked all the address but it is still the same. I wasn't sure if I was flashing at the begging but I configured the PB7 pin to be GPIO output and connected to a led and the led is working so I can flash it and...

Hi, how the real power heating current will be a for a pwm signal will be mesured in average? TrueVrms? Or will be the same like normal current. The singal is 0 to 5v. Not negative value, so is more like pulseing dc. For example, two led vf=2v connected to 9v 250ohms with a frequency of 10%hz...

I am using PIC16F877a microcontroller. My aim is control the servo motor with pwm signal. I can create the pwm signal with RB0 pin with ccs c code. I have tried the ccp1 module to create pwm signal but I could'nt. Why does not work. And I have a question about these two ways to create pwm...

I am a mechanical engineering student so only have a basic knowledge of electronics. I am using some RGB LEDs and I want to control their colour temperature and brightness. I am controlling the colour temperature with PWM but want to control the brightness with another method so the colour is...

I am working on a project (based on the PIC16F18877) to which I am planning on adding a PWM DC brushless fan. However, I have never had to work with PWM before (or even DC fans) so there are a few things I am not clear on that I am hoping to get clarification on. I just want to make sure I...

Hi folks I am trying to build a circuit which will govern the speed of the fans in my solar cabinet based off the temperature inside. https://www.circuits-diy.com/temperature-controlled-fan-using-555/ I built this circuit hoping it would work with 6x 24v / 0.08A PC fans (40mm) I have 3 of...

So I have a circuit whereby a PWM signal is being sent to a demultiplexer, and the demultiplexer sends the signal to a MOSFET which takes it and allows a current to flow through the nixie tube. The higher voltage value in the original PWM signal, the more the nixie tube will light up. My issue...

I am trying to control a linear drive motor with a built-in encoder. I am using a motor driver to move the linear motor. I have calculated a PWM signal for a PWM frequency of 1kHz and a duty percent of 50% with the following values: Internal Clock = 180 MHz Prescaler = 180 Arr register...

Hi, I made a really simple PWM generator but the mosfet placed in the circuit keep getting damaged even though they are not heating up. The load in the schematic is a 20ohm heating element but i also tried to replace it with much led and resistor but the mosfet still get damaged after 1 or 2...

Hi all, I am trying to build some underwater lights for my boat. I am using 10 pcs of 3W RGB 6 pin leds in series and i have tested the output. I am currently using a constant current constant voltage driver. I would like to make a pcb capeable of driving the 10 leds and controling them with...

Hi, I have returned to an old issue I am struggling with – my door lock solenoid project again. I have created a really simple LTSpice circuit driving my solenoid at 1Khz, 50% duty. The solenoid I measured with an inductance meter, 35mH and 25R series resistance, this has been entered into the...

Hello all, I have encountered an AHC244 chip used to drive LEDs (Something like in the attached image) so I wondered why not just drive the LEDs with the uC pins? And also I have seen this IC used with some PWM signals as inputs to it! in this case, I am guessing the output would be the same...

Please help me to understand this circuit about analysis voltage each point and how to calculate time charge and discharge time on triangle signal. If use Op-Amp NJM2904C Thank you.

Hello, I have an arduino Uno that I am trying to use to control a 12v motor. I need to control this motor. I have tried using the analogWrite(); method, and also changed the frequency but still could not get my valve to move. This valve can be controlled via linbus or pwm according to the...

Not usually one for asking questions in forums, as I'm usually able to find solutions with my own research, however, I've been looking at this over a period of days now, and the deeper I dig, the more confused I'm getting.. I'm a Computer Science student, not electronics, so please go easy on me...

hello I have a practical task to make a simple LED lamp. I was using LDD-1000 for that purpose. But it does have minimal duty cycle of 20% (output is filtered so it's 20% of max. current) . Was looking for an alternative that could provide smooth control of current from 0A to 1A. Kinda lost in...

I am attempting to use a thermistor to control the PWM of a 555 output. Ideally, I want the duty cycle to be 100% when hot (~90°C) and 0% when not hot (~25°C). I am doing so by placing the thermistor as R2 (RB) in astable mode with a forward biased diode in parallel to R2 (allowing a duty cycle...

Hi, This probably isn't super complicated but I have to control 3 stepper motors simultaneously with an esp32 for part of a robotic arm. These are the nema 23 stepper motors I am using, they are normal open loop 4 wire stepper motors. These are the motor drivers I am using. One pin tells...

I want to make a circuit that will convert a PWM signal to an analog signal. I want the circuit to be able to work on higher frequencies as well though (up to 15 kHz). Would an RC filter be the best method? Any reference design examples for this?

I'm trying to determine a standard PWM frequency output for RGBW controllers. I see a lot of constant current LED chips call out a maximum PWM frequency input between 300 and 500 Hz. 1. I assume this indicates that 300 to 500 Hz is standard? I've seen a 12 Vdc 385 Hz RGBW controller pass FCC...