Questions tagged [pwm]
Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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How to Drive a 50uA Panel Meter with a PLC Running 24v Inverted PWM Signal
Full disclosure, I am not an engineer of any kind. Just an electronics enthusiast.
I have a Barth 850 micro PLC that needs to operate at 24v, and has one PWM output. I also have a 50uA panel meter ...
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How can I implement current control for proportional valves?
I am currently working on operating a proportional valve for airflow, but I am facing some challenges. Initially, I attempted to control it using a DRV8871 motor driver with PWM frequencies of 500 Hz, ...
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How to eliminate relay buzzing when turning on and off
I'm using one of these relays to power some LED's using a trigger wire that outputs either 0V, 50mV, or 12V. The relay has a low voltage trigger setting that turns on when there is anything less than ...
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Convert square wave to DC using opamps
For a project I need to convert a 0-24V 200Hz square wave to DC.
The DC is supposed to represent the duty cycle of the square wave signal.
From this website I drew inspiration.
I've made a 2nd order ...
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Can PWM be stacked?
My project currently looks like this. I set the top analog output to a fixed value around 3V (it varies from board to board, depending largely on the behaviour of the vactrols), and vary the lower ...
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Building a constant current circuit [closed]
The constant current output should be able to be set from 0.2 mA to 20 mA with a load of 3500 ohms ±50% from a 5V battery source and a PWM signal set by a microprocessor. Do I need a transformer or ...
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How to create a PWM source with fixed frequency and decreasing duty cycle (at some interval) in LTspice?
I'm trying to simulate a PWM signal whose duty cycle decreases by a fixed amount over a given interval from 100% to 0. For example, if the PWM frequency is 2 MHz, I want to ramp down the on-time from ...
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Calculating a gain of a PWM Modulator with triangle carrier
I'd like to ask for help with calculating a gain of a PWM modulator using a triangle wave.
I know how to calculate a gain in case with a sawtooth carrier with turning-on at the start of cycle.
and
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Trying to power a 12 V LED underglow system using PWM signal from dome light
I've learned a lot from the brilliant minds on this forum so far, and I think I've narrowed my original question a bit.
I'm trying to create an entry light effect in my car using my LED underglow ...
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A simple solution to the PWM controlled DC fan?
I am trying to temperature control a set of 12V DC fans (2 wires) of mine.
I went down the pwm microcontroller output + mofset rabbit hole (increases the noise / can damage the fans), read about RC ...
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WCCA analysis - Induction selection - Mismatch with recommendation at low current values
I'm performing the WCCA analysis of a 3.3V buck regulator(AP64200Q).
Datasheet: https://www.diodes.com/assets/Datasheets/AP64200Q.pdf
In the current circuit:Vin=24V,Vout=3.3V,Max.current=300mA so ...
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Ferrite Topology For Motor PWM
Brushed motors are pretty noisy devices, especially when driven with PWM. There are a number of techniques to reduce the transmitted noise (twisting wires, shielding etc) - one of these is using a ...
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How to filter a noisy PWM signal without affecting rise and fall times
I need to read the frequency and duty cycle of a PWM signal that is expected at 88Hz. It is getting a lot of noise (during radiated immunity).
Before noise:
After noise injected:
What filter would ...
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VGA signal on STM32 blackpill
I am trying to build a simple VGA video card using the STM32F401 Blackpill with max clock frequency of 84Mhz. I am aiming for a resolution of about 640x480 at 60hz. I tried using timers and PWM to ...
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Is keeping average current low a way to avoid damage to PSU and MOSFETs?
Here’s the scenario: I have to power two heating plates which drain 18 A each but the PSU is only rated 32 A. The initial plan was to attach each plate to a MOSFET module rated 30 A and control them ...
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Motor Driver Project using 555 Timer PWM + 4N25 + 2N7000
I need to build a circuit that controls the speed of DC Motor using external potentiometer, here are the requirements of the project:
Power source: two 12V dc, 450mA power supplies
Motor: R140 Micro ...
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Duty cycle in Sine PWM and Conduction Losses in a MOSFET [closed]
I'm trying to understand an analytical expression for conduction losses in an MOSFET based inverter. In the derivation given in a paper, the usual starting point is the definition of the duty cycle:
&...
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Maximum voltage/current on a passive 8 ohm buzzer
I have a buzzer with:
8 ohm
1 watt rated power
Resonant frequency: 700/600 Hz
In order to make it sound, should I apply a PWM with 700/600 Hz, and turning ON and OFF?
What is the maximum voltage? ...
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Issue with LED Strip Brightness using Arduino Mega and N-Channel MOSFETs
I'm working on a project to control a white LED strip (SMD5630) with an Arduino Mega (ATmega2560) using N-Channel MOSFETs (IRL530). The goal is to dim the lights using PWM signals through the digital ...
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Controlling PWM Fan/Read Sensor from PIC16F18877
I am working on a controller based around the PIC16F18877 which will need to control a 4-wire 12V DC Fan, as well as read the signal from the sensor wire. The PWM signal needs to be somewhere between ...
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Variable voltage control from an ESP32
First, the background context:
I have a pair of these TCS-300 landscape lighting controllers which have a cloud-only control interface, which cannot be integrated with my local home assistant.
My goal ...
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Interleaved PWM Generator for DC-DC Converter
I have an PWM signal ready from opamp which has an switching frequency around 10KHz what can be done to obtain an interleaved version (T/2 Delayed version) of this signal
FYI,
I have used sawtooth ...
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How can I read a high frequency PWM falling edge with Arduino interrupts?
My project is about a Magnetic Levitator. I control the electromagnet with a high frequency PWM signal which I use on the MOSFET gate to give to it enough current.
The thing is that I use a linear ...
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Maximum PWM Frequency from a MCU [closed]
I am designing a high-frequency SMPS with custom MCU and gate driver controlling network. I am hoping to have a controlling network with no limitations in controlling frequency. If I use a timer/...
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Fluctuating brightness in RGB-LED strand controlled by Arduino
I am controlling the three colors of an RGB strand using PWM output from an Arduino UNO (via IRF520N MOSFETs). When the signal to the LEDs is in midrange, the strand starts to visibly pulsate at a ...
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PWM switching, Regarding the control voltage
If V desired and V actual is subtracted, in this diagram, how does the V control which should be very same used as reference? My question is that, the V control can be very small, how can it be able ...
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Reducing EMI from PWM controlled Led segments
I am currently designing a product that has a ring of LEDs with 7 individually dimmable segments.(all together about 40 standard (blue/white)LEDs max 15mA each) the only supply voltage is 3.3v but I ...
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PWM from the Robodyn AC light dimmer
I am currently conducting a test on a Robodyn AC light dimmer product, and I want to check the PWM trigger output from the controller. Due to equipment limitations, I am only checking the trigger from ...
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Advice about power MOSFET layout and heat management
This question is a continuity to my previous one: Weird DC motor behaviour at low PWM duty cycle
Here is my circuit schematic:
The motor is a LEM130 from Lynch Motors (about 2 kW and 50 A rated power/...
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Weird DC motor behaviour at low PWM duty cycle
I am back with my brushed DC motor PWM project.
From all the previous replies I got, I've settled with and built a simple one MOSFET circuit as follows:
The motor is a LEM130 from Lynch Motors (about ...
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Controlling TRIAC with PWM from microcontroller
I am looking to control a mains heater with a microcontroller. It seems like most solutions use an optocoupler to signal the microcontroller at a zero crossing and another optocoupler to trigger the ...
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PWM on desired pin PIC18f47k40
trying to question again.. Thanks in advance for any help!
I've been working with PIC chips for a while and recently using a PIC18f47k40. I cannot get the PWM via CCP or the separate PWM modules to ...
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Controlling LED drivers with a PWM using a PIC MCU
In one of the circuits I'm working on, there are three LED's connected to every LED driver output (I have a space and cost constraint because of which I need to use this). The high side of each LED is ...
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LED Spot and LED Strip dimming problem
I have two 555 timer circuits, each one identical to the circuit below but the "load" is different in each circuit. In the first timer circuit, the "load" is 6 x 2m 12V LED strips (...
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FFT on my oscilloscope is not detecting a peak which is a peak
I am having a strange problem and it's due to that lack of my info about signals.
I examined a PWM output from my MCU under sds1104x-e oscilloscope which is 656KHZ with a duty cycle of around 45.5% ...
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Add PWM control to XL4015
I am using a circuit based on XL4015 to drive a series of high power leds. After that circuit I have a mosfet to dimmer the led. With this configuration everything woks fine.
Now I want to unify both ...
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I want go find the Part no of this PWM controller
I want to know the part no of PWM controller. In upper side it is written 53T0 and in lower SZAB has been written. Please help me to find this.
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Problem with faulty treadmill PWM controller [closed]
I am trying to repair a treadmill PWM controller board.
The power MOSFET (IXTH13N110) is burned out completely with all 3 pins are shorted, and as it's a bit expensive, I can't risk to replace it and ...
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How to run fans out of phase?
I am working with server fans. The noise generated by these fans is quite disruptive, and I've read that running them 180 degrees out of phase could potentially reduce the noise.
I'm looking for ...
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Buzzing ringing in boost converter regulator when using PWM in lower duty cycle
I designed a boost converter using TI LMR62014XMF, to convert 5 V to 12 V for using as backlight source in my LVDS display adapter.
The LCD display panel needs 12 V at 0.5 A max for backlight driving.
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pwm 0-5v to 0-12v , what's wrong with this circuit
What is wrong with this circuit.
I'm trying to control a 12v solenoid from a cnc board. At 1kHz and 10% pwm I get around 5v and 12v at 15%. Not 0-100% = 0-12v. I ended up with this circuit by looking ...
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Did a PWM fan tach signal fry my ESP8266?
I spliced two PWM fan tach wires and connected them to a single ESP8266 GPIO pin. Since I tried powering this on I couldn't get the ESP8266 back up and running, even after disconnecting the splice ...
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Smooth a PWM to DC stable [closed]
I have to smooth a PWM (0V- 12V, 200Hz) who trigger my pic12f1572 via transistor 2N3904. What is the best way?
I have PWM source connected to 2N3904 and output from 2N3904 is connected to PIC uc. I ...
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I have a RBGW LED controller that is 4CH*4A but I need a controller that is 4CH*1.5A. Is there an easy way to make this 4CH*4A controller work?
I have a RBGW LED controller that is 4CH*4A but I need a controller that is 4CH*1.5A. Is there an easy way to make this 4CH*4A controller work? The controller is a PWM controller.
Could I simply add ...
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PWM Driver for PIC12F1572
I have rear lights for car (VW Passat) controlled by default with PWM. I want to create another circuit who do like follow:
When I press brake, car send PWM into LEDs and turn it ON. I want to use ...
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PWM circuit that switches MOSFET with soft edges [closed]
I've recently bought a soldering iron from China that buzzes audibly as it heats up the tip. I'm trying to understand the reason it makes the buzzing sound and mitigate it. What I observe is that as ...
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Low Percentage PWM LED Brightness (Equation?)
I have a 5 V embedded circuit where a 10 kΩ pot controls the duty cycle of an LED. I noticed that when the duty cycle is only 0.39% (or 1/255 bits), the LED is still perceptibly bright. I'm looking at ...
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How do you size a resistor when the current and voltage flowing through it are impulsive?
Given a 33 Ω resistor, I need to size the power it can handle. The resistor is in series between a pin where a SPWM voltage is applied and the gate of an IGBT.
In the following photo: blue is the ...
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Brushed DC Motor - Driving Forwards With PWM AND Detecting Reverse Motion
I would like to drive a small 9V brushed DC motor using PWM from a micro-controller and came up with the standard circuit of: micro-controller PWM out (J1) connected to a mosfet gate with a current ...
