Pulse-width modulation, is varying the duty cycle of a rectangle wave, usually with a constant frequency.

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45 views

An overall PWM system by using FPGA

I need to combine this 3 coding to form one whole PWM system by using FPGA. I tried it, there is no error, but the process is not synthesizable. Please help me. Thank you. This is code for ...
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1answer
49 views

Controlling high voltage PWM [on hold]

I want to use Arduino(or others) digital pins with PWM to get below outputs. Voltage 0-50V, Pulse amplitude: 0-100mA, Pulse width: 0-200us, Frequency: 0-1kHz I need your help and suggestions for ...
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0answers
16 views

How to decrease the absorption voltage in the case of an MPPT with fixed settings

I have an MPPT solar charge controller which doesn't have any option to input the custom settings. Though it works fine for new batteries but as my battery, Flooded Lead Acid 150AH, is little old and ...
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0answers
17 views

Best PWM IC for LED Driver [on hold]

I am confused to choose best PWM IC for my LED bulb Driver (Offline flyback SMPS converter with primary sensing) Specification- Input-90v to 265v AC Output- 150mA constant current, 40V DC Please ...
0
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1answer
20 views

Is the PWM rail of a 4pin pwm Computer fan Positive or negative

I am wiring a 4 pin computer fan to a 12v dc power source and I am wondering the pin for the PWM is positive or negative.
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1answer
40 views

SMPS buck convrter with PWM controller circuit

Hi there I am designing a buck converter run on PWM circuitry for a uni project to drive a MOSFET switch and keep my output voltage constant. The specs are: input voltage of 20v DC +/- 4 output ...
0
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3answers
67 views

N-Mosfet switch circuit strange behavior laboratory power supply

I'm dealing with an N-Mosfet switch circuit to control, through PWM, the temperature of a heater resistor. The mosfet is a IRFS7430-7PPBF. The load is driven at 12V and has a power rating of 80W. ...
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0answers
70 views

100Khz 150W LED Switching

My test Circuit is 5V VCC + LED + n-MOSFET(Controled by OPAMP for constant current) + n-MOSFET(For ON/OFF) +(feedback)+ Shunt Resistor + GND. 5V/30A SMPS. If there is no n-MOSFET for ON/OFF. It's just ...
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2answers
42 views

Permanent magnet DC motor earth wire

I have just inherited a piece of equipment that is powered by a 12V DC permanent magnet motor. My hope is to drive it using an Arduino PWM and a H-Bridge to manage the current requirements (7.3A ...
2
votes
2answers
28 views

Current chopping with an h-bridge and PWM

I have some stepper motors and L298N dual h-bridge drivers. I can't find exact specs for the steppers,* but similar motors from another product line have rated voltages from 2.64v to 5.8v. Since most ...
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1answer
25 views

Independently toggling two series switches to multiply two pwm signals

Preface It is known that one can synthesize a signal into a train of boxcar pulses (pwm modulation), each with the same amplitude, if proper low pass filtration is applied to this pulse train before ...
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0answers
15 views

What's the peak voltage of the sawtooth generated by the ic SG3525 or UC3525? Does it depend on the Ct capacitor?

P.S. I need this information in order to make a closed-loop FlyBack CC-CC converter. The Tm transfer function is related to the sawtooth peak voltage: Thanks!
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3answers
61 views

Generating a (ideally several) PWM signal from GPIO, alternative to software-based pulse

Scenario: I am trying to control precisely (without glitches) several servo-motors from a computer through GPIO. Final position, speed and ideally acceleration need to be controlled. Currently I ...
-1
votes
1answer
52 views

0-5V PWM to analog 0-24VDC voltage with MOSFET

Im having trouble understanding how or if it even is possible to regulate a voltage with a MOSFET. I want to regulate an output voltage of 0-24VDC 0.5A(continuosly) with the duty cycle of a 0-5V 1kHz ...
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3answers
59 views

Directly driving 5V source MOSFET H-Bridge with 3.3V logic

I am trying to design a H-bridge circuit for my project to drive a thermoelectric cooler (TEC). Basically, I am trying to control the TEC with a voltage source driven by PWM. Now the problem is, I ...
0
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2answers
47 views

Positive to negative PWM converter

I am looking for a way to convert a + 24V square wave coming from a cnc controller, to -5V. The frequency of a square wave will vary from 15kHz to 35kHz. What methods would you suggest? Thanks for ...
0
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0answers
108 views

Ringing at the output of a microcontroller

I'm generating a pwm signal of 125khz, I've no problems with the frequency but the signal has an overshoot: This is a big issue because I'm using this signal to control a dc/dc converter and the ...
0
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1answer
52 views

PWM to DC converter with op amp - slowly but steadily rising output voltage

I assembled a circuit to convert a PWM signal generated by an Arduino to a DC voltage in the range 0..10 V. I use the 10k-10u RC filter to convert the PWM signal to DC voltage in the range 0..5 V, ...
0
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1answer
40 views

pwm amplifier with npn bjt

I'm trying to do a pwm amplifier in order to control 3 fans with one pwm signal. Since there are three fans and according to the pwm specs allowed current per each is 5-8mA, I expect current load of ...
0
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1answer
34 views

Servo control with 555 timer

first of all this is for an assignment so I have certain limitations, mainly cost. The problem I'm having is I have run out of PWM inputs on my ATtiny45 but I still want to drive a servo. The two PWM ...
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2answers
84 views

Sending PWM signals down cat5 cable

I working on an LED lighting project where I will be installing 20 boxes in a space, each containing 4 LEDs (RGB and IR.) I want to connect all of these boxes to central board which will drive all of ...
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1answer
75 views

How does PWM generate an analog signal?

AFAIU, PWM works as follows: According to the value of the counter in the microcontroller, a square wave is generated at a designated output pin of the \$\mu C\$. The duty cycle of this square wave ...
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1answer
50 views

Not being able to enable PWM using the HAL TIM library on stm32f0

The goal is to use the PWM feature of stm32 HAL TIM libraries to light up 4 leds on pins 0, 1, 4 and 5 I have generated the following code using CubeMX: ...
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1answer
39 views

Dimming LED lights with PWM, driver quite far from LEDs, noise considerations

There were a few questions like this before, however I haven't found ultimate answer yet. I'm going to drive LED lights in my house with multi-channel driver (PWM controller + MOSFET Transistors), ...
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1answer
30 views

PWM with alternative load

I want to drive an ~220V incandescent bulb with arduino's pwm, any suggestion about the stage to put between them.
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1answer
42 views

Calculating the input current drawn by a MOSFET driver

I am using a PIC32MZ's OC pins (PWM mode, fault disabled) as input to a dual MOSFET driver (ISL89163 A). I need one OC pin to drive 3 drivers i.e 6 inputs each. The pulse width would be around ...
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1answer
55 views

Help comparator circuit for this PWM signal inverter

I have 2 signal (signal on the left) and how to combine those 2 signal into the signal on the right, I have try using lm 741 op amp, but unfortunately the output signal is different from the ...
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1answer
102 views

LED light dimming, TRIAC vs PWM?

Many days ago, I published a question here asking about dimming an AC LED using and Arduino and TRIAC, and I was told that most LEDs that support dimming should work with the circuit I linked to them. ...
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0answers
21 views

Ohmic Power Loss of the Peltier Element (PWM Vs Linear current)

I want to design a circuit to drive the Peltier element. The first option is to drive the peltier with PWM and the other option is to use a sync buck convertor, which is likely adding LC filter to ...
0
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1answer
27 views

Setting up PWM on PA.3 of the STM32F091RC Nucleo board

I am using STM32Cube and the HAL libraries to set up the PWM. For initializing Timer 2, I have: ...
0
votes
2answers
55 views

Blocking DC when driving a buzzer with a PWM signal

I am driving a piezo buzzer with a PWM signal (typical freq. 100Hz-1kHz) in order to generate 'beeps'. However due to software constrains (*), when the PWM signal is stopped I can't control if it ...
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votes
1answer
45 views

How to use two timers simultaneously to control 2 servo motors

im very new to PIC. Im trying to control 2 servo motors for the wheel of my robot. Im using PIC16f877A MCU, servo motor and 4 mhz crystal oscillator. I use mikroC compiler. Actually i already have a ...
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0answers
41 views

Do I need to worry about FCC emissions when using PWM?

I have a AC-connected (though an adapter) unintentionally radiating device that runs a large DC motor (12v, ~6a continuous) under <10khz PWM control. Naturally, switching this large a motor ...
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0answers
34 views

Replacing DPDT Relay with MOSFETS

New here so if this seems like a dumb question then excuse me, but I have an issue and I need to replace this relay with MOSFETS. The issue is I plan on using the following MOSFETS for the two in the ...
0
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2answers
96 views

PID and motor control by PWM

I am having a potentiometer which gives an analog voltage in range of 0-5V. I am considering this POT as throttel input for motor. If i change the pot speed increase and decrese on the basis of ...
0
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2answers
78 views

PWM driven power supply [closed]

As you have asked me, I will explain in better words my problem. I'm working on real-time bench. I have an algorithm on my laptop and I interact with hardware through a calculator supporting real-time ...
0
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1answer
29 views

switching power loss calculation in sinusoidal pulse width modulation

How do i calculate the switching power loss in sinusoidal pulse width modulation SPWM in a H bridge inverter (4 IGBTs), and precisely is it linearly proportional to the frequency switching or to the ...
1
vote
1answer
51 views

How to regulate 2x130W peltier modules

I built a small fermentation chamber (cooling box) based on the peltier modules. I know this is not very optimal way as peltiers are not very efficient, but I had my reasons for choosing this way. ...
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1answer
22 views

When using conventional means to control a heating element, how does it affect the peak required VA?

This question is similar to two others, here and here, but with a small difference. To allow a bit of context: Suppose I have a winters day with lots of sunshine. I have an off-grid PV system, and ...
0
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3answers
116 views

Can I somehow use one PWM output to set various LEDs to different brightness?

I would like to build a project in which 15 groups of LEDs are set to a brightness level. I have an Arduino with digital PWM outputs (which can mimic a range of voltages.) How can I do this? One ...
4
votes
1answer
161 views

SMPS Buck converter with PWM circuit

I am designing a buck converter with PWM circuitry for a school project to drive a MOSFET switch to keep my output voltage constant. The specs are: input voltage of 20v DC +/- 4 output voltage of 5v ...
1
vote
1answer
94 views

FPGA Frequency Divider

I need to design frequency divider from 50MHz to 200Hz using FPGA. I'm using Xilinx and the language that I used is VHDL language. I got stuck because I can't get the output. So, anyone can help me? ...
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1answer
74 views

PWM or Variable Resistor [closed]

For a school project, I have to design and perform an experiment of my choice. I have chosen to test the efficiency of variable resistors and PWM circuits by testing the amount of energy wasted (heat ...
0
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1answer
111 views

Best way to convert 5V DC to 110V AC at 50Hz for pdlc film drawing 2mA max. Size is the thing!

I'm working on a project in which I'm hoping to integrate several small segments of pdlc film, which starts off diffuse white/'frosted', turns clear when excited with 110V AC at 50Hz and is apparently ...
0
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1answer
75 views

Why is the DC motor receives higher voltage from the PWM than what is given?

While I was trying to find the gain (K constant) of a motor, I gave different voltages to see if I will have the same gain constant in each of them. While doing it, I come through an issue. When I ...
0
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0answers
70 views

PWM + Strobe Light using Arduino on 100W LED?

I want to create something like the Sunblaster by DIY Perks, but I want to include a PWM regulation and a strobe function using an Arduino. I want to use this boost converter to drive a 100W LED. I ...
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2answers
68 views

Is PWM or voltage control the most efficient way to control a heating element? [closed]

I am thinking about a heating controller for my electrically heated motorcycle coat. It draws about 6 amps at 14V on my motorcycle. My question is whether it is more efficient to drive a heating ...
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1answer
58 views

ATmega48PA: can not run PWM on OC0A and OC2A pins

I have some troubles trying to run Fast PWM on OC0A and OC2A pins. The code is the following: ...
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2answers
72 views

Some question on SERVO MOTOR [closed]

Basically we give a PWM wave to the control input, but what will be the input for the error detector...? How is this PWM wave converted to some voltage value that can be compared from the ...
3
votes
5answers
424 views

Improving PWM by using comparison to LFSR instead of counter

PWM is a very powerful technique to simulate an analog output from a microcontroller, programmable logic or any other digital environment. This can be used to drive LEDs, motors and speakers, etc... ...