Questions tagged [pwm]
Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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RC Snubber Design Hint for 3 phase AC-AC PWM Chopper
Im trying to design a 3 phase Ac-Ac Pwm Chopper, I'm having difficulty designing the snubber network for the mentioned topology.
Now I tried testing this circuit on bench , with my IGBT snubber values ...
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Getting "servo jitter" when trying to move Actuonix actuator slowly. Works fine when going from 1-2 ms in RC protocol
I have a PQ12-30-6-r Actuonix actuator that's moving erratically. When I set the width of the pulse from 1-2 ms then it will move down immediately, and vice versa back up. I can go to 1.5 ms as well, ...
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Unicorn Mode PMOS For Hurricane Flooded Golf Cart Controllers
We have saltwater flooded golf carts after hurricane Ian. Their old 0-5k Ohm throttle pots are shot, and replacing them is very expensive. The new throttle systems can be fitted more cheaply, but ...
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Please help identify this SMPS IC
I need to repair a charger for an e-bike. The model is SHC-8100L made by stchargers.com.
The unknown IC (marked U1 here, a 3x2 mm SMD IC marked 71427) seems to be faulty.
Input voltage seems to be on ...
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Hardware based PWM fan solutions
HPE DL360P’s love to run these fans (8x of them) at max speed. I don’t really need them all running, but wasn’t sure if dummy plugs to just trick the motherboard was a good idea. Wiring length and ...
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Issue with LDO in a PWM high current circuit for heating element
I’m building a circuit to control a heating element using a ESP32 as MCU.
The circuit is simple. A 2S lipo battery (8.4 V) as power source and 2 N-channel MOSFETs controlled by PWM in order to ...
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Driving low side NFET with TC4420 and 24 V supply. I can't understand my prototype results
I've created a circuit using a gate driver IC, TC4420, which allows me to dim a 24 V LED strip using 20 kHz PWM from an Arduino UNO. I got some help the other day and attempted to make a small scale ...
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H-bridge: Low-side N-channel MOSFET burns occasionally
I am just getting into electronics and my first project is a 555 timer PWM (0-100) and an H-bridge to drive a motor for my brewing equipment (500 mA max. rating).
Here is the setup:
I have a 12 V ...
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BLDC MOSFET Driver Bridge - High side not achieving full voltage, low side always grounded
I have been designing a BLDC controller using IR2101 gate drivers to control high/low MOSFETs. Please see schematics below.
After soldering everything on and testing circuits, I am not getting the ...
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How does the control of a three-phase PWM rectifier work?
I have been studying the control of three-phase PWM rectifiers i.e. control of the below power electronics circuit:
This circuit can be modeled with exploiting of the space vectors in the stationary ...
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Pulse generation using Timer counter in ATMEL SAM3x8e Arduino Due
I am using the ATMEL SAM3x8e chip on an Arduino Due. I want to generate two pulses of frequency 100 kHz of the pattern shown below (1 period shown). For this I used TIOA8 and TIOA0 lines in the ...
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How to generate a pulse burst train by 1MHz PWM in STM32 M0+?
I need to generate a pulse burst train. In each burst, there are 120 pulse with pulse width of 1us. And in between the bursts, there is a interphase width in 130us.
I set TIM1 as 1MHz PWM with Duty ...
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In LTspice simulation Voltage spikes are observerd across drain and source of MOSFET
I am simulating the below circuit on LTspice.
A PWM signal is applied to the gate of MOSFET M1.
I expect to see a waveform similar to gate source waveform across the drain and souce of the MOSFET. ...
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Capture PWM duty and polarity
This question is a spin-off from earlier post about DC motor emulation. I've decided to split the questions to keep them more on point. Assuming I can successfully trick the driver into thinking the ...
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RL circuit with PWM as an input turn the ground to negative
RL circuit with PWM as an input turn the ground to negative.
I'm trying to limit the current of RL circuit by using PWM.
This how it works, for 15 ms the circuit receives constant voltage to charge ...
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Using a SSR for passing a DC PWM Signal that has positive and negative waveform
I am trying to control the PWM signal to a solenoid via an SSR by passing one leg through it to control the on/off.
I have tried 3 different SSR's and none of them fully stop the signal, I still get a ...
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Why is the grid current of this single-phase AC/DC rectifier not an AC sinusoidal waveform?
I drew a single-phase AC/DC rectifier in PLECS and used bipolar PWM to control it.
Here's my calculation process and related parameters (the duty cycle of Vtri is 0.5):
I think my calculation is ...
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Tuning motor temperature
I have a DC motor, running in two modes, slow and fast. I will need to run the motor in FAST mode only. The motor is already running for 10 years. The motor experiences variable load.
According to the ...
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Shunt FET PWM best practices?
I am designing an LED driving circuit using an AL8861Y-13. Like any switching regulator, its PWM resolution/frequency are limited.
I want to do higher frequency and resolution, so I have opted for a ...
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Commutation BLDC Motor with Complementary PWM produces slower speeds than Independent PWM
'"a complementary PWM can be used, which will also reduce the power dissipation in the devices".
That means using Complementary PWM makes the MOSFET cooler. However, in my program, using ...
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How to generate PWM from based on an AC signal?
I'm working on a project to improve the efficiency of the resonant wireless charging system. For one of the steps to do this, I need to find the phase shift between current and voltage and of \$I_{\...
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ESP32 PWM: How far can it go and how many things can I control per pin?
I am designing lights lights for my fish tank and came up with the idea of using modular pucks of LEDs on small custom PCBs. This modular design would be easily scalable and reusable for future ...
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PWM signal generator circuit does not work in real life
I designed the motor soft start circuit in the figure below.
I ran the circuit in simulation programs, but when I tried it on a breadboard in real life, I could not get a PWM signal.
When I examined ...
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Can i use ESP32 3.3V pwm on MG90D Servo
Ok so, im building the eletronical part of a sumo robot for my university team, and i came to a barrier, on past researchs we came to the conclusion that using MG90D servo is the best option for us (...
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How does the COMP/EN pin of the MAX1967/MAX1966 work?
I know this question may seem simple to more experienced people but I struggle to understand how the COMP/EN pin works on this particular IC.
I want to use it for a buck converter that has external ...
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Implementing burst mode control in a continuous PWM switching scheme
I am designing an inductive adder with two modules where a low-side MOSFET operates under continuous PWM switching in each module. However, my intended application for this adder would require ...
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Protections for bidirectional motor controller circuit for DC brushed motor
I am designing an H-bridge based DC motor controller. It should be able to control 4 quadrant operation of a DC motor, therefore I am using four STB85NF55T4 MOSFETs and four IN58198RL Schottky diodes ...
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STM32F7: Two timer channels share one DMA channel
I am trying to write a driver that sends DShot commands to an ESC. I am using an STM32F722 MCU. The DShot protocol is similar to addressable LEDs where 1/3 duty cycle represents a 0 and a 2/3 duty ...
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Reading ADC value of sensor with PWM source
As the topic mentioned, I have been working on getting ADC value of a sensor that is driven by a PWM source. I've come across a situation that when I am getting the ADC value with a rather long time ...
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ATTiny406 | Unexpected PWM (Pulse Width Modulation) Output
We are experiencing strange PWM (analogWrite) behavior on pin PA3 of our ATTiny406 when our supply voltage exceeds ~11VDC. This pin is driving a MOSFET which controls the ground signal to the LED ...
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