PWM Driver#

PWM Driver

The PWM driver uses one or more TIMER peripherals to generate one or more PWM waveform, with configurable frequency, duty cycle, and polarity.

Multiple instances of the driver can be created and allocated to their own TIMER channel.

The duty cycle of the PWM waveform can be updated, while the PWM driver is running by calling sl_pwm_set_duty_cycle(), without causing glitches in the output waveform.

Note

• If several PWM driver instances are set up to use the same TIMER instance, the PWM frequency of these instances must be the same.

PWM Example Code#

Basic example for generating PWM waveform:

#include "sl_pwm.h"
#include "em_gpio.h"

int main( void )
{

  ...

  sl_pwm_instance_t sl_pwm_led0 = {
    .timer    = TIMER0,
    .channel  = 0,
    .port     = gpioPortA,
    .pin      = 0,
    .location = 0,
  };

  sl_pwm_config_t pwm_led0_config = {
    .frequency = 10000,
    .polarity  = PWM_ACTIVE_HIGH,
  };

  // Initialize PWM
  sl_pwm_init(&sl_pwm_led0, &pwm_led0_config);

  // Set duty cycle to 40%
  sl_pwm_set_duty_cycle(&sl_pwm_led0, 40);

  // Enable PWM output
  sl_pwm_start(&sl_pwm_led0);

  ...

}

Modules#

sl_pwm_instance_t

sl_pwm_config_t