mc68hc908mr8 Freescale Semiconductor, Inc, mc68hc908mr8 Datasheet - Page 160

• Manufacturer Part Number: mc68hc908mr8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Pulse-Width Modulator for Motor Control
Technical Data
160
UP/DOWN COUNTER
PWM VALUE = 3
DEAD-TIME = 2
PWM1/PWM2
MODULUS=4
DEAD-TIME
OUTCTL
PWM1
PWM2
OUT1
OUT2
NOTE:
DEAD-TIME INSERTED AS PART OF
NORMAL PWM OPERATION AS
CONTROLLED BY CURRENT
SENSING AND PWM GENERATOR
Figure 9-19. Dead-Time Insertion During OUTCTL = 1
2
complimentary operation is in use, the odd OUTx bits are inputs to the
dead-time generators as shown in
whenever the odd OUTx bit toggles as shown in
dead-time is not inserted when the even OUTx bits change, there will be
no dead-time violation as shown in
Setting the OUTCTL bit does not disable the PWM generator and current
sensing circuitry. They continue to run, but are no longer controlling the
output pins. In addition, OUTCTL will control the PWM pins even when
PWMEN = 0. When OUTCTL is cleared, the outputs of the PWM
generator become the inputs to the dead-time and output circuitry at the
beginning of the next PWM cycle.
To avoid an unexpected dead-time occurrence, it is recommended that
the OUTx bits be cleared prior to entering and prior to exiting individual
PWM output control mode.
Pulse-Width Modulator for Motor Control (PWMMC)
DEAD-TIME INSERTED DUE
TO SETTING OF OUT1 BIT
2
Figure
Figure
9-14. Dead-time is inserted
9-20.
MC68HC908MR8 — Rev 4.1
Figure
DEAD-TIME INSERTED
DUE TO CLEARING OF
OUT1 BIT
Freescale Semiconductor
2
9-19. Although