Freescale Semiconductor MC68HC908MR32 - Manual (Page 136)

Pulse-Width Modulator for Motor Control (PWMMC)
MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1
136 Freescale Semiconductor
Figure 12-23. Dead-Time Insertion During OUTCTL = 1
Figure 12-24. Dead-Time Insertion During OUTCTL = 1
UP/DOWN COUNTER
MODULUS = 4
PWM1
PWM2
DEAD-TIME = 2
OUTCTL
OUT1
OUT2
2
PWM1/PWM2
2 2
DEAD-TIME INSERTED AS PART OF
NORMAL PWM OPERATION AS
CONTROLLED BY CURRENT
SENSING AND PWM GENERATOR DEAD-TIME INSERTED DUE
TO SETTING OF OUT1 BIT DEAD-TIME INSERTED
DUE TO CLEARING OF
OUT1 BIT
PWM VALUE = 3
DEAD-TIME
UP/DOWN COUNTER
MODULUS = 4
DEAD-TIME = 2
OUTCTL
PWM1
PWM2
OUT1
OUT2
2
PWM1/PWM2
2 2
PWM VALUE = 3
DEAD-TIME INSERTED BECAUSE
WHEN OUTCTL WAS SET, THE
STATE OF OUT1 WAS SUCH THAT
PWM1 WAS DIRECTED TO TOGGLE DEAD-TIME INSERTED
BECAUSE OUT1 TOGGLES,
DIRECTING PWM1 TO
TOGGLE NO DEAD-TIME INSERTED
BECAUSE OUT1 IS NOT
TOGGLING
DEAD-TIME
2