Questions tagged [pwm]
Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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Generating two PWM signals from a PIC18F45K20
I'm doing an environmental control group project for my embedded systems module. I want to generate two PWM signals:
Control fan speed from ADC readings from a TMP36
Dim an LED strip depending on ADC ...
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Sending PWM signal over Cat5
I'm trying to send PWM signal to MOSFET gate to control 12VDC 2A motor. The NE555 circuit is built as shown in this article (https://www.build-electronic-circuits.com/555-pwm-circuit/) with the same ...
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Linear AC voltage to DC 5v or 10v PWM conversion
I have a vehicle with generator style speed signal generator and its output is linear from 0 -30VAC. This signal is used by the Dash mounted speedo without any issue. I now have a mandated requirement ...
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3 'Phase' BLDC Motor Control using Raspberry Pi 5
I am making a project to control speed and position of multiple 3 Phase BLDC Motors using a Raspberry Pi 5. I am struggling with the number of PWM channels I will need and the lack thereof on the Pi ...
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Will 400 Mbps be enough to transmit a 5 kHz PWM signal?
PWM signal to be generated from MAX6966 at 5 kHz with duty cycle varying from 1% to 99%.
This PWM signal is fed into a line driver SN65LVDS1. Then using a 10 meter shielded twisted pair of wire, this ...
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Voltage Spikes with PWM Controlled Brushed Motor
I have disassembled a 20V cordless drill. It uses a two-lead brushed motor controlled via a PWM signal. Out of curiosity I connected both motor leads to an oscilloscope and measured both against a ...
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PWM demodulator implementation
I was browsing the web for the prior works on the PWM demodulator implementations, and I found patent US4408166A, "Pulse width modulation decoder" from 1982.
I cound not obtain the vo ...
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What’s the difference between using PWM and H-bridge circuits for controlling DC motors in robotics? [closed]
I’m working on a small robotics project and trying to control DC motors. I’ve come across terms like PWM motor control and H-bridge circuits, but I’m a bit confused. From what I understand, PWM is ...
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How to verify ADC data sampling aligned with center-aligned TIM8 PWM on STM32H743 without oscilloscope?
I am working on an STM32H743 project where I need to read ADC data synchronized with a center-aligned PWM signal generated by TIM8. My goal is to ensure ADC sampling is correctly aligned at the center ...
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Can't get sound from AST0940MCQ
I'm stuck with simple AST0940MCQ, I'm not able to get any sound from it, here is my sch
R41 is connected to MCU where I generate a PWM signal 4kHz, check with my oscillo pwm is fine. If I check ...
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Problem with the totem pole gate driver on bipolar transistors
I need to make a gate driver for a P-channel mosfet. I plan to use a PWM signal from a microcontroller with a maximum amplitude of 3.3 or 5V. After searching for a circuit on the Internet, I found ...
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Sending DSHOT frames from a Nucleof4 development board to an esc
I’ve been working on implementing DShot150 on an Nucleof4 development board using HAL drivers with DMA, driven via a timer. I followed the DShot using HAL drivers implementation and even extracted the ...
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Level translator for a PWM signal
I'm working on a circuit that converts a 3.3V PWM signal to 5V (level translation). I'm trying to implement this using a single MOSFET. The circuit works fine at lower frequencies, but at higher ...
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PWM signal delay (distortion) at transformer
The transformer (Mfr.Nr.: PH9400.111ANLT) is causing a delay of about 50ns on this 150KHz, 3.3V PWM signal.
Are there hints to deal with this delay and distortion? This signal (S1) is driving a MOSFET ...
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Parallel NPN BC547 for increase current demand of PWM controlled fan
My fan requirement is 180mA while the transistors I have has a maximum collector current rating of 100mA, thus, I resorted to using a parallel arrangement as shown.
I have done some calculations &...
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FOD3180 only switches above 12.5V, while the datasheet specifies a maximum threshold of 9V
I'm using the FOD3180 as an optocoupled gate driver to drive the gate of an N-channel MOSFET (STB130NF7) in a low-side switching application.The application is intended to switch at 10 kHz, with the ...
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Low pass filter for PWM audio
I want to add sound to a microcontroller project, using PWM, and I came across this blog post with the circuit below.
With a cutoff frequency of 100Hz, doesn't this heavily attenuate all audible sound ...
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Need help in confirming the circuit and the results. I am converting a PWM signal 0 - 5 V to analog 0 - 10 V
I am trying to convert a PWM signal generated from MCU which can only output 0 - 5 V but I want to drive an ECM fan which requires 0 - 10 V analog so I am using a MOSFET to switch 10 V supply by ...
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Change signal duty cycle
I have a 2 kHz PWM signal (500 µs period). The pulse width varies from 125 µs to 250 µs and can take any value between them. How can I double the pulse width duration, and as a result, the duty cycle ...
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PWM-controlled Buck Converter MOSFET heating up and signal too rippled
I have the circuit below with all the components the same, except the PMOS being a SQD50P04-13L_GE3 MOSFET. The PWM signal that is sent from the STM is from a 216 MHz clock with prescaler 100 and ...
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Formula for Inductor Charge and PWM Duty Relationship
I am running some tests on a wye wound BLDC to understand the relationship between duty cycle and charge for a given PWM period. I am slowly linearly increasing the duty cycle off just one phase. ...
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PWM DAC Considerations
Consider the following PWM D/A Converter that I would like to use. I saw a similar concept once on a commercial device, and since I now need an adjustable voltage with high resolution, but not fast ...
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PWM Output Channel Speed
I'm a mechanical engineer with some light knowledge of electronics. I might not understand immediately, but whatever knowledge you provide I'm sure with enough hours of googling I'll be able to figure ...
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Can PWM DAC convergence be improved by taking into account the previously commanded output voltage?
Suppose the current output (and, therefore, capacitor voltage) is 0V and the PWM DAC is commanded to output AVDD/2. Conventionally, it would set the duty cycle to 50% - which is the value that works ...
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DRV8837 motor driver inconsistent behavior
I designed a PCB using the DRV8837 motor driver. While testing it, I'm getting some behavior that I don't understand so I was hoping someone could shed some light here. My circuit is pretty much just ...
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