COMPLEMENTARY PWM

COMPLEMENTARY PWM  AT 5KHz

PROGRAM (for C language)

//i have used crystal of 16 MHz  and no PLL 
//output at 5KHz
void main()
{
    unsigned int pwm_period, current_duty ;
    current_duty=500  ;                   //duty ratio 31%
    pwm_period = PWM1_MC_Init(5000, 0, 0x11, 0);      //enable 1L AND 1H pwm pins
    PWM1_MC_Set_Duty(current_duty, 1) ;
    PWM1_MC_Start();
    //DTCON1=0                     //DEAD TIME CONTROL
    while (1);
}

PROGRAM (for pascal language)

'i have used crystal of 16 MHz and no PLL 
program BLINK
dim pwm_period, current_duty as word
main:
    current_duty=500  'duty cycle of 31%
    pwm_period = PWM1_MC_Init(5000, 0, 0x11, 0)   ' Pwm_Mc_Init returns calculated timer period.
    PWM1_MC_Set_Duty(current_duty, 1)
    PWM1_MC_Start()
    while (TRUE)
    wend
end.

COMPLEMENTARY PWM  AT 60KHz  

PROGRAM (for C language)

//i have used crystal of 16 MHz
//output at 60KHz
void main()
{
    unsigned int pwm_period, current_duty ;
    current_duty=100  ;                   //duty ratio 50%
    pwm_period = PWM1_MC_Init(60000, 0, 0x11, 0);      //enable 1L AND 1H pwm pins
    PWM1_MC_Set_Duty(current_duty, 1) ;
    PWM1_MC_Start();
    //DTCON1=0                     //DEAD TIME CONTROL
    while (1);
}

PROGRAM (for pascal language)

'i have used crystal of 16 MHz and no PLL
program BLINK
dim pwm_period, current_duty as word
main:
    current_duty=65                     'duty ratio 50%
    pwm_period = PWM1_MC_Init(60000, 0, 0x11, 0)   ' Pwm_Mc_Init returns calculated timer period.
    PWM1_MC_Set_Duty(current_duty, 1)
    PWM1_MC_Start()
    while (TRUE)
    wend
end.

HOW TO CALCULATE PWM DUTY CYCLE

• PWM duty ratio depend on output frequency
• 16MHz  crystal as clock source
• PRESCALE VALUE ARE  1, 8, 64, and 256

Maximum duty ratio =( (F_OSC  /(F_OUTPUT  * 4  * PRESCALE VALUE)  -1)*2

FOR 5KHz
Maximum duty ratio = (16MHz / (5KHz *4 *1)  – 1)*2=1598

FOR 60KHz ,Maximum duty ratio = (16MHz / (60KHz *4 *1)  – 1)*2 = 130
I HAVE USED 50% DUTY RATIO FOR BOTH

COMPLEMENTARY PWM  AT 240KHz

PROGRAM (for C language)

//i have used crystal of 16 MHz
//output at 60KHz
void main()
{
    unsigned int pwm_period, current_duty ;
    current_duty=100  ;                   //duty ratio 50%
    pwm_period = PWM1_MC_Init(60000, 0, 0x11, 0);      //enable 1L AND 1H pwm pins
    PWM1_MC_Set_Duty(current_duty, 1) ;
    PWM1_MC_Start();
    //DTCON1=0                     //DEAD TIME CONTROL
    while (1);
}

PROGRAM (for pascal language)

'i have used crystal of 16 MHz and PLL of 4
program BLINK
dim pwm_period, current_duty as word
main:
    current_duty=65                       'duty ratio 50%
    pwm_period = PWM1_MC_Init(60000, 0, 0x11, 0)   ' Pwm_Mc_Init returns calculated timer period.
    PWM1_MC_Set_Duty(current_duty, 1)
    PWM1_MC_Start()
    while (TRUE)
    wend
end.

COMPLEMENTARY PWM  AT 60KHz WITH DEAD TIME CONTROL

'i have used crystal of 16 MHz  and no PLL
program BLINK
dim pwm_period, current_duty as word
main:
    current_duty=65                       'duty ratio 50%
    pwm_period = PWM1_MC_Init(60000, 0, 0x11, 0)   ' Pwm_Mc_Init returns calculated timer period.
    PWM1_MC_Set_Duty(current_duty, 1)
    PWM1_MC_Start()
    DTCON1=15
    while (TRUE)
    wend
end.