Questions tagged [pwm]
Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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Using a coupled inductor in a multi phase buck converter - how to set the inductor dot notation and converter PWM for best ripple reduction
Based on these Charles Sullivan papers, we can use a coupled inductor in a multi phase converter to reduce inductor ripple current.
https://www.princeton.edu/~minjie/files/sullivan-CICC-2021.pdf
http:/...
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How to connect an LED driver to an Arduino
How do I connect two of these SCT2024 LED drivers to an Arduino?
This is what I have so far: I'm connecting each output to an N-channel MOSFET. I'm not sure about the other pins from the datasheet.
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space vector modulation harmonic injection (zero sequence) [closed]
I'm having a hard time trying to get my head around this, its relative to a 2-level 3-phase inverter supplying a balanced resistive inductive load . I cant seem to find much information is it similar ...
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Will the frequency change when converting the ESP32 3.3 V logic to 5 V logic using a TXS0108E?
The GPIO on ESP32 (S3) are all 3.3 V logic. I want to control an ESC for a drone. The manufacturer says:
The ESC will use a standard 5 V PWM signal at 50 Hz between 1100 µs and 1950 µs. 3.3 V output ...
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12V fan drawing more current when connected to 24V power supply. Why?
I am developing a fan that runs with 3 speeds, that can be connected to a 12V or a 24V battery, I have attached the circuit below, PB0 converts the voltage divider to ADC and based on the value the ...
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In STM32F4 Complementary PWM, Can we set %0 dutycycle both CH1 and CH1N
My question is about complementary PWM. Can we get %0 dutycycle at CH1 and CH1N at the same time. Datasheet of MCU: https://www.st.com/resource/en/reference_manual/rm0383-stm32f411xce-advanced-...
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UC3844 IC duty cycle problem [closed]
Recently I started building a flyback converter with a targeted input voltage of 12-24 V and output voltage of 150 V. The swicthing frequency is set to 100 kHz, for testing purposes I've used a ...
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Circuit for high-voltage pulses using Raspberry Pi PWM to drive a piezoelectric actuator
I am trying to engineer a device to separate red blood cells from blood plasma in 100mm x 1mm capillary tubes using the Raspberry Pi GPIO pin PWM feature and a piezoelectric actuator.
The pulses ...
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Is BLDC speed controlled by Frequency or by average voltage [closed]
I am trying to understand the control loop for an off the shelf BLDC gimbal kit (SimplBCG 32 Bit extended with GM8112 Motors. My understanding of most BLDC control loops is that they use hall effect ...
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PWM driven 24 V fan noise issue
I have a weird issue with a 24 V blower fan. We are driving it with an N-channel MOSFET at a PWM freq of 12 kHz. It has a periodic artifact that appears about 230 Hz or so.
Observable behavior ...
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DRV8262 not working with PWM signal
I designed a motor driver with the new Texas Instruments DRV8262 at its core. It will be used in robots controlled by an ESP32.
It works well when using non-PWM signals to switch the outputs in PWM ...
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RC filter to DC 12V, 3A fan PWM
This feels like a question asked hundreds of times before, yet doesn't seem to have a good solution. If a company could sell me a solution, I would buy it in a heartbeat.
I have a van with a 3A 12VDC ...
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How does a microwave oven modulate its output power?
My microwave has multiple power settings, ranging from 500 watts to 1500 watts. My question is how is the power reduced/modulated?
I can think of a few options (but I don't know which one is correct/...
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PWM on STM32F411 is not working using timer1
I am trying to use this code to control brightness of a LED using channel 3 of Timer 1 (PA10 pin) on the STM32F411:
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How to calculate PWM duty cycle to compensate for different piezo sounder response at different frequencies?
How to calculate PWM duty cycle to compensate for different piezo sounder response at different frequencies?
I have a piezo sounder, and the datasheet informs me that I will get the following ...
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Unable to Generate PWM Signal Using CCP of PIC16F15325
I am using: Curiosity LPC dev kit, PIC16F15325, MPLABX v5.35 on Mac, XC8 compiler. I am able to blink each LED on the Curiosity.
My goal is to generate a PWM signal on RC5 to drive an LED on the ...
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Sabertooth 2X12 Motor controller unable to control DC motors(UPDATED)
This is a follow from my previous question about the Sabertooth 2X12 motor controller.
I aim to control DaNi Robot’s motor using the sabretooth 2X12 controller. After reading the datasheet, a few ...
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Detect presence of 12MHz squarewave without oscilloscope
I have programmed my ESP32 to (supposedly) output a 12 MHz clock signal, to use as a substitute for a broken clock crystal on another microcontroller. The code I used is adapted from this esp32 forums ...
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NUCLEO-L432KC timer PWM frequency problem: PSC and ARR values not resulting in desired PWM frequency
I have been trying all day to use timer 1 channel 1 of a nucleo-L432KC (with a STM32L432KC MCU) to generate a PWM signal of frequency 50 Hz (pulse width 20 ms). I tried many, many, MANY different ...
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How to adjust duty cycle of an existing square-wave, based on light level
I am making a wall-powered, battery-backed, BCD alarm clock with discrete logic.
I'd like to adjust the brightness of the LEDs based on light level, as this clock will be used on a nightstand. So ...
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Motion controller using brushed DC motors
I've designed a simple robot with 2 active wheels and 4 omni wheels and I'm trying to figure out the motion controls.
I'm using 8300 RPM motors (https://uk.rs-online.com/web/p/dc-motors/3213192) which ...
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Is it OK to drive an LED matrix with constant current?
I bought one of these LED matrix modules as described in this Adafruit PDF.
The PDF says: "they do not have built in PWM control of any kind. Instead, you're supposed to redraw the screen over ...
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C2000 PWM skips a compare on synchronization
I found a mitigation for the problem that I couldn't post to e2e.ti.com because they demand a company email (University won't do). See my self-answer below.
I'm using a TI microcontroller ...
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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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The resistance value for PWM circuit uses STM32F103C8T6 and MOSFET
I want to design a PWM circuit using STM32f103C8T6 and MOSFET as shown below.
I use MOSFET IRF3708 because Gate-to-Source Voltage low. but low power.
MOSFET IRF3205 has a large power but Gate-to-...
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Name of this 4-pin fan connector
I have a 40mm fan with a connector that has standard breadboard pin spacing. I would like to connect it to what I thought was a relatively standard fan connector that has wider spacing (and thicker ...
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How to understand the minimum operating time of motor drive?
When researching PWM control of brushed motors, I noticed that the motor drive data sheets usually have the following time descriptions.
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SPWM - Frequency calculation
Below is the SPWM I produced with 50 Hz sine wave and 5 kHz carrier signal. I will use the SPWM signal to drive the MOSFETs in my inverter.
As it is known, duty and period are constantly changing in ...
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Laser Power Control Using Duty Cycle
I have a Coherent Cx-10 CO2 laser that I want to use for laser heating of very small samples at high pressure, so I need to accurately control the laser power. I also have a pulse width modulated ...
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How is the sweep of duty cycle handled in common microcontrollers? [closed]
I have designed a PWM module in Verilog, and it was giving me a glitch. After debugging it for some time, I found that the value of the duty cycle was changing twice within a certain period.
How do ...
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What does TIM_OCMode do on STM32F4?
I'm making locked antiphase drive for motor control on STM32F4 board. Im configuring Timer4's 4 channels to be in pairs, ch2 inverse of ch1 and ch4 inverse of ch3. Each pair will control its own motor....
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Is there a way to use PWM to control AC mains powered heater?
Is there a way to use PWM to control the power and temperature of a mains powered heater? I know that I could use a TRIAC but I am just wondering. I know what PWM is and what is it used for, but ...
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Welding machine schematic: PWM controller connections
I don't understand why the VFB pin of the UC3845AD PWM controller is grounded, and why the compensator pin is connected to the output of the LM224 through VD1 and VD2.
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TRIAC Controlled Motor circuit: PWM logic doubt
I'm working on the logic board of my kitchen air extractor. I wanted to "hijack" the controls (physical buttons) to be able to control those with an ESP8266. While I was analyzing the ...
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Identifying PWM IC with marking on device M01 35 (package is SOT23-6)
I am trying to do some repair on a internal DC adapter (Topow POW 3102A ver : 1.1 ) for BigBen ST01 iPod/iPhone Docking Station where I found this 6 pin ( package sot23-6) PWM IC marked M01 35. I am ...
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Damage to inverter: Using excess solar photovoltaic to power water heater like trailing edge dimmer
Motivation
I know that a similar question has been asked before (control power to water heater,) but prices and technology have changed, and my situation is slightly different so I am asking again.
My ...
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Debugging the triangle wave generation using ISL7044
I am trying to simulate an Analog PWM circuit as shown in this TI application note.
Link attached here => Analog PWM TI Report
However, I have a requirement to achieve the same using ISL70444 OP-...
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Why does slow-decay mode increase torque of brushed DC motor under PWM?
I am working on a project requiring high torque operation of a brushed 12V DC motor at low speed, plus software speed control from a microcontroller. PWM is the obvious choice here.
My driver supports ...
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Adjusting Output Voltage of a DC-DC Boost Converter controlled by STM32 PWM
I'm building a boost converter from scratch and am planning to use an STM32 microcontroller to generate a PWM signal to regulate the output voltage. The power supply voltage of the circuit is 24 V, ...
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How can I avoid saturation in current source amplifier?
I'm designing a class d amplifier with current feedback as in figure below
with the following features:
Vbus=50V
Iout programmable from 100mA to 1A rms
Vout=35Vrms max
When the load overcomes the ...
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PWM vs mutiplexing, why one can control the apparent brightness and other saves power?
In an LED grid where we are using multiplexing to control a ton of LEDs, where we are scanning each row quickly and using persistence of vision to enjoy the full picture at once; let's say that there ...
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Convert a faster-slower PWM signal into a forward-reverse
I have come upon an aircraft RC controller, and I wanted to use it to build a small robot / car.
I realise that an aircraft is not a robot, but I have come this far and feel like it should be possible ...
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Simulation of Transistor - Ltspice
I produced spwm to drive high side mosfet.
I made a simple note gate from a pnp transistor to receive the inverse of the signal I produced.
PWM-A/ is the opposite of PWM-A and both are 5V. So far ...
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Dimming LEDs with MOSFET circuit causes low voltage devices to fail
I am a rookie with electronics and have an issue that is beyond me. To set the scene: I have a number of custom-made circuit boards, all performing different tasks as a part of some automation I am ...
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Sinusoidal BLDC LUT synchronization
I am trying to control a 3-phase BLDC motor. I have already done 6-step commutation, which works fine. Now I am going for sinusoidal control. I have studied more about sinusoidal control in BLDC and ...
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LTspice - simulation of SPWM is giving unexpected result
I am trying to make SPWM with op-amps. I also made a simple NOT gate with a simple transistor.
The first op-amp is working well when its output is not connected. When I directly connect the first op-...
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SG3525 feedback identification
This is from a UPS which creates 350VDC from 12VDC, How does this arrangement work to control presumably the duty cycle of SG3525?
Compensation (pin 9) and inverting input (pin 1) are connected ...
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100 kHz PWM motor driver PCB/cable considerations
I am designing a board to drive a DC micromotor which requires a 100 kHz PWM signal. The board is mainly a digital design board, with very little analog signalling.
I am planning on driving the motor ...
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PWM signal for DC motor vs voicecoil
I'm working on a project where I want to design my own current driver to drive different kind of loads. A friend of mine lent me a motor, an Arduino UNO to generate the PWM and half-bridge IC (L293D) ...
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Oscilloscope drawing - low-pass filter
I'm doing a project that can draw an analog clock on the XY mode of an oscilloscope using the Atmega88-20PU with the default clock frequency of 1MHz. To display the image I use a PWM signal applied to ...
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