Questions tagged [duty-cycle]
Duty Cycle is the ratio between duration of a pulse and the entire period of a (repeating) square wave, expressed in %.
197
questions
3
votes
1
answer
47
views
Can I use a brushed DC motor at higher-than-rated duty cycle at reduced load?
I have a linear actuator powered by a brushed DC motor which I got from an adjustable bed. The actuator label has the following information:
Input Voltage: 24V DC
Max Load: 6000N (Push)
Speed: 4.2mm/...
- 141
0
votes
1
answer
75
views
Two formulas for defining RMS and average of a waveform through a diode [duplicate]
A textbook problem where we have this given current waveform through a diode.
We are required to determine the maximum and RMS values of it [ Irms and Ip ] giving the average current= something ...
- 39
3
votes
3
answers
491
views
RMS of sine wave curve defined between two points
Could someone explain for the following attachment (waveform image) how were exactly the values of "RMS" and "average" determined this way (for that curve of sine)?
Given the duty ...
- 39
0
votes
0
answers
58
views
How to choose Duty Cycle value for a Full-Bridge DC/DC Converter
I've noticed that while designing DC/DC converters, some sources (at the bottom of the website, comment of Benjamin Lough) suggest a "rule of thumb" duty cycle of 70%, while others (This is ...
0
votes
0
answers
36
views
Why is Duty cycle for CC LED driver voltage specific, when Output voltage has a compliant range?
Commercial CC drivers usually mention "x-yV output" range which means that the output voltage has a compliance range where CC operation will be maintained in constant current mode. But then ...
- 407
0
votes
1
answer
67
views
Can one CC boost LED driver be used for 2 different loads separately?
I have a constant current boost LED controller (TPS92691) which I am designing to output 4A switching between two LED strings. This is with a 2S lipo battery. One string has a stack forward voltage of ...
- 407
0
votes
1
answer
115
views
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 ...
- 600
1
vote
0
answers
311
views
STM32 24VDC PWM fan speed control with optocoupler
I am using this circuit to control a 24V fan at a frequency of 31kHz (MCU - 72 MHz, Prescaler - 9, Counter period - 255):
The scheme works. But I want to add an optocoupler to the circuit, I did it ...
- 11
0
votes
0
answers
29
views
Why is it difficult to write the close loop transfer function of a frequency modulated DC-DC converter (for eg - LLC converter)?
I know how to derive and write the transfer function of duty cycle/pulse width modulated DC-DC converter. We need to linearize the switches and then write KVL/KCL equations and then derive the output ...
2
votes
3
answers
354
views
How to create a PWM source with fixed frequency and decreasing duty cycle (at some interval) in LTspice?
I'm trying to simulate a PWM signal whose duty cycle decreases by a fixed amount over a given interval from 100% to 0. For example, if the PWM frequency is 2 MHz, I want to ramp down the on-time from ...
- 639
2
votes
1
answer
135
views
Boost converter duty cycle
In my circuit, I’m trying to solve the duty cycle to obtain an average dissipation of 5 W in the diode.
Input voltage: 100 V
Inductor: 10 mH
RL: 100 Ω
C: 10 uF
Freq: 10 kHz
Diode on voltage: 0.7 V
...
- 57
0
votes
1
answer
35
views
PWM switching, Regarding the control voltage
If V desired and V actual is subtracted, in this diagram, how does the V control which should be very same used as reference? My question is that, the V control can be very small, how can it be able ...
- 137
0
votes
2
answers
153
views
Voltage not varying with duty cycle
I want to make a circuit that changes voltages with the duty cycle as well as doubles that for me. I therefore made a voltage doubler circuit along with alternating PWM wave. But as I changed the duty ...
- 669
0
votes
1
answer
31
views
Understanding violation of the common mode voltage range of the input in ZCD [closed]
Trying to reproduce an analog circuit using LM324 to have at output 100Hz squarewave 5% duty cycle from 230Vac mains frequency.
The circuit has to be in sync with it. Picture and LTSpice simulation ...
- 3
3
votes
4
answers
508
views
Schmitt trigger transistor duty cycle
I built this Schmitt trigger using transistors (2N3704).
Input is a square wave coming from an OCXO, 1 MHz, 50% duty cycle.
I obtain a square wave with 70% duty cycle. What can possibly be the cause?
- 176