334 Generador PWM multiproposito con frecuencia y ciclo de trabajo modulable
334 : Generador PWM multiproposito con frecuencia y ciclo de trabajo modulable
- Author: Marco Vázquez, Paúl González, Abimael Jimenez, UACJ
- Description: A PWM generator with a 6-bit input that allows the user to enter a denominator that divides the frequency. Using a pair of control inputs, we can increase or decrease the duty cycle of the modulated output by 10%.
- GitHub repository
- Clock: 5000 Hz
How it works
Overall, the module converts a high-speed clock signal into a PWM signal with adjustable frequency and duty cycle. The user receives a high-frequency clock signal and, through a frequency divider, generates a lower-frequency clock. Then, they control the high duration of the PWM signal using buttons that increase or decrease the duty cycle value.
A 5kHz signal is received; the 6-bit divider only accepts numbers from 2 to 63 (decimal). The possible output frequencies for the PWM range from 2500Hz (5kHz/2) to 79Hz (5kHz/63), which can be used in different electronic components such as RGB LEDs, servomotors, stepper motors, sensors, and other circuits.
How to test
- Connect the clock signal: Assign a high-frequency clock.
- Apply the reset signal: Initially set the reset to high to restart the module. This will reset all counters and the duty cycle to their initial values.
- Set the frequency divider: Define the frequency divider value to adjust the speed of the clock used. This value controls the PWM signal frequency. A higher divider value will result in a lower PWM frequency, and vice versa.
- Duty cycle adjustment buttons: When activating the increment button, the duty cycle will increase by 10%. When activating the decrement button, the duty cycle will decrease by 10%.
Recommendation: Use the PWM signal only as a control signal; the power supply for the devices it is applied to should come from an external power source.
External hardware
The PWM output should go to a PMOD to have that control signal available on a device.
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | increase_duty | pwm_out0 | |
| 1 | decrease_duty | pwm_out1 | |
| 2 | divisor[0] | pwm_out2 | |
| 3 | divisor[1] | pwm_out3 | |
| 4 | divisor[2] | pwm_out4 | |
| 5 | divisor[3] | pwm_out5 | |
| 6 | divisor[4] | pwm_out6 | |
| 7 | divisor[5] | pwm_out7 |