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Pwm And Duty Cycle

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307 Threads found on Pwm And Duty Cycle
Hello!! I have problem with my project Speed control of DC motor using KEYPAD and pwm. I have interfaced 4x3 Keypad and 16x2 LCD, I want to control speed of DC motor using keypad input like 25% duty cycle 50% duty cycle etc.!!! My problem is in program ..that is I cannot (...)
Hi I want to adjust TL494 for one open-loop smps with 45% duty cycle and 100khz pwm on the output. There is a problem with the output pwm wave form(pin9 & pin10). Rise time is about 500ns and fall time is about 2.5 us. How can I correct the fall time? I think it is too high. Its the (...)
Hi, usually one does not need to have both parameters variable. The usual way is to set the 100% current for the LEDS with the resistor and do the brightness adjust with the pwm duty cycle. **** If you want the current to be variable, then you could use different shunt resistors and MUX the signal, or (...)
pwm-ed lower two MOSFETs together at 7KHz with duty cycle 4-20% for testing "Together" means what it says? Switching-on left and right low side simultaneously? 4% duty cycle might be already too much, depending on transformer leakage inductance. How did you measure currents? Did you look (...)
hi, I want implement a constant current source with pwm control. 10mA is required at a load 1Kohm. The pwm should turn ON and OFF the load . The pwm frequency is 100Hz to 1KHZ with duty cycle of 10% to 80%. Regards
Hi All, I want to drive 32 channel pneumatic valve with XC3850AN FPGA by using 32 channel pwm. Can any one guide me how to start. Valve starting voltage should be 24V for 840ms and pwm duty cycle for remaining ON time should be 25%.
my dspic33ep512mu810 has pwm 1 Low Output pwm 1 High Output what is the meaning of high and low in pwm kindly explain.if i am using pwm to generate 1000 pulses at 50 % duty cycle how to connect in high and low pins of pwm
Hi, I donīt know what microcontroller you use.. As a general answer: With an 1Mhz clock (1us period time) .. and you want 100us pwm period time you need a 100 step counter. Usually a counter from 0...99. Now you want 40% duty cycle you need a "digital comparator" (Its inside a pwm generaton module) with (...)
can someone explain PID control logic for pwm duty cycle given below --> Lets say output refrence voltage are 2.5V If voltage are changed (transient change) from reference "V" Change pwm duty cycle accordingly to maintain 2.5 output only using PID control logic Assumption (...)
At 100% duty cycle PIC is not giving always high signal Why? How to get rid of this fault? Can I edit default existing pwm library in MikroC? PIC Used : 18f4550 Tool: MikroC Pro for PIC void main() { TRISC = 0 ; // set PORTC as output PORTC = 0 ; pwm2_Init(1000); (...)
It looks like you copied my improved Plants Watering Watcher circuit but added a variable capacitor to where the wet soil was. The variable capacitor ruins the pwm output when the dampness of the soil (its resistance) between A and B changes the duty cycle of the pwm then the filtered output on your copy (...)
Hello,I would like to implement a VFD with PIC16F1937 and mainly IR21362 and Power MOSFET ,could you please help me to deal with those Codes,I made a 120degrees phase shift but the capabilities of making the frequency and amplitude adjustable remain difficult for me,please help,find the codes here below: #define NUMBER_OF_TABLE_ENTRIES_FOR_
Does anyone know how to generate the waveforms as shown in the attachment? I have made it by swithching a pin on and off with fixed frequency but I want a more intelligent program for this purpose. Can anyone suggest some module of any PIC microcontroller that can implement such pwms? The duty cycle needs to be same for both (...)
I want to drive the Full bridge configuration for the dc to dc converter. I want to use the two output pwms from the microcontroller according to this 126942 I also want to vary the duty cycle according to the change in the input voltage. I'm using PIC18F4550. Also, I want to control Full bridge with two output pwms fro
pwm is good for controlling motor speed. But why do you want to change the frequency?
Hi, Are you saying that if i remove that resistor the circuit will work fine. Try it. In such case, how Q1 will be switched on without Cboot having charge and same in next operation for Q3. Don't worry. Try it. There are several scenarios...all will work. The best solution is, that you i itialize your microco
Decide the max frequency you will be using. Decide the max current (or input voltage) you will be using. Decide the max and min duty cycle you will be using. From the core and winding data, determine the max energy per cycle (pwm frequency) stored in the core. Select snubber based on (...)
I want to control dc motor 24 v 11 A using plc . so i need a driver circuit that is able to work on 24 volt pwm from the plc. what are your suggestions?
I have problems reading ADC value, I have left justified result and need to read the bit 7 & 6 from ADRESL and save the value into CCP1X and CCP1Y to control the lowest bits of my pwm duty cycle. I have searched in my header file, but cannot find there how I can read the bits from ADRESL, (...)
hello everyone. I am making a three phase inverter to control the speed of induction motor placed at the O/P of inverter. I am using potentiometer as analog input and using it to vary the duty cycle and freq of gate signals. I am facing an issue right now. arduino UNO has 6 pwm pins. I am using them (...)