Questions tagged [pwm]
Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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Why is the filter capacitor (used to filter pulsing DC) overheating MOSFETs in a buck converter?
I am trying to create a microcontroller (Arduino) based DC to DC buck converter with CC and CV features. For now, I am using a 20 V 5 A input source. Output voltage (target voltage) is settable by the ...
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PWM Dimming of a Low-Voltage DC Incandescent Filament (Thermal Shock?)
I plan on driving some Numitron tube filaments from an IV-16 tube (datasheet here). For ease of access I'll give the key specs here:
Nominal filament voltage: 3.15V
Max filament voltage (steady-state)...
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PWMs from microcontroller are resetting
I have been designing an SMPS where the STM32F334R8t6 microcontroller provides the full bridge control signals. The microcontroller board uses a 5 V and 3 V regulator to supply the MCU and the CAN ...
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P channel MOSFET for PWM Peltier control (Arduino)
I want to control the power of a Peltier device using a MOSFET PWM controlled by an Arduino.
In order to "smooth" the power going to the Peltier, I want to add a capacitor in parallel.
The &...
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4-pin 12 V PC fan - manual speed control
I've been reading a little about 4-pin PC fans, but haven't been able to find a clear answer.
I understand the PWM pin controls the fan's running speed, so if I wanted to use a 4-pin fan for a non-PC ...
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How measure fan signal that not seems to the ground isolated?
I have voltronic inverter 3k fan stops with code 01 its mean fan need a replacement
old fan in pic-01 its use us62 ic so i order new fan pic-02 and its not working
first reason the cables reversed ...
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BLDC Thermofan PWM Controller design recommendations
This circuit is intended to drive small automotive cooling fans (~70W)
The gate drive IC is failing when starting from a stall and pops instantly. If current is limited on startup to around 5 A, ...
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Adjusting shift phase of PWM dinamically does not work in STM32
I need to get two PWM signals (PWM1 and PWM2) from STM32F767 Nucleo board when programing with STM32CubeIDE, which are applied to a Full-Bridge DC-DC Converter. PWM2 must be shifted phase in reference ...
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How can I properly use PWM to observe hopefully >= 2x normal efficacy, seeing the theoretical max of 1700 lm/W scotopic efficacy?
In a Wikipedia article on "Scotopic Vision", there is a section that states:
The maximum scotopic efficacy is 1700 lm/W at 507 nm (compared with 683 lm/W at 555 nm for maximum photopic ...
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Problem with the triggering the 555 monostable trigger
I am currently making a dual speed dc motor circuit that is controlled by 555 timers. My goal is to have DC motor full speed below 2V and between 2-3V, the DC motor spins half-speed using PWM from 555 ...
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Expected voltage when probing a computer PWM-fan socket's sense pin?
I'm using my multimeter to probe a proprietary 6 pin socket on the motherboard of a PC computer that connects to 2 small 25 mm fans. The socket's pins are unlabeled. Both the motherboard and socket ...
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Verify whether the Motor Driver has PWM Support
I was looking for a single channel motor driver with a supply voltage range of 6V - 12V and a continuous current range of 2A. I came across a motor driver IC called SS6285L. This motor satisfies the ...
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Convert PWM negative signal to either On or Off signal
I am trying to make a simple conversion circuit to take a negative PWM signal from my cars dome lamp signal and simply make it or or off. I believe I should be able to use a PNP transistor and ...
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Thermal efficiency circuit to move an DC electric actuator with PWM
I am looking for a circuit to move an electric actuator with PWM.
The actuator is 12V (datasheet) and the normal operating current is ~2A but can reach 8A maximum under some conditions. For that ...
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Change analogWrite() frequency using the arduino framework for SAMD51
I am using Adafruit Feather M4 Express board which has Atmel SAMD51 controller on it. I am using platformio as IDE, which lets me use this controller using the Arduino framework.
I want to change the ...
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