CHANGING ARDUINO PWM FREQUENCY In some projects like boost and buck converters we may need to change the default frequency of Arduino PWM pins according to our need in order to control the charging time of inductor. in Arduino UNO pins D5 and D6 have PWM frequency of 62500 HZ , pins D3, D11, D9 and D10 has the default PWM frequency of 31250 HZ . To change the PWM frequency following code can be written in setup function to set PWM frequency Divide the base frequency of pins by the factor you want to decrease the frequency for each pin some examples are shown below The divisors available on pins 5, 6, 9 and 10 are: 1, 8, 64, 256, and 1024. The divisors available on pins 3 and 11 are: 1, 8, 32, 64, 128, 256, and 1024. for D3 and D11 TCCR2B = TCCR2B & B11111000 | B00000001; // for PWM frequency of 31372.55 Hz TCCR2B = TCCR2B & B11111000 | B00000010; // for PWM frequency of 3921.16 Hz TCCR2B = TCCR2B & B11111000 | B00000011; // fo