mc68hc708mp16 Freescale Semiconductor, Inc, mc68hc708mp16 Datasheet - Page 152

• Manufacturer Part Number: mc68hc708mp16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Pulse Width Modulator for Motor Control (PWMMC)
9.6.3.1 Manual Correction
Technical Data
152
NOTE:
The IPOL1–IPOL3 bits select either the odd or the even PWM value
registers to use in the next PWM cycle.
The IPOLx bits are buffered so that only one PWM register is used per
PWM cycle. If an IPOLx bit changes during a PWM period, the new value
does not take effect until the next PWM period.
The IPOLx bits take effect at the end of each PWM cycle regardless of
the state of the load okay bit, LDOK.
The best time to change from one PWMVAL register to another is just
before the current zero crossing.
waveforms under high current and low current conditions. During a
Pulse Width Modulator for Motor Control (PWMMC)
Figure 9-20. Internal Correction Logic when ISENS[1:0] = 0X
IPOL1
IPOL2
IPOL3
Bit
PWM CYCLE START
EVEN PWMVAL REGISTER
PWM CONTROLLED BY
ODD PWMVAL REGISTER
Table 9-5. Top/Bottom Manual Correction
PWM CONTROLLED BY
IPOLx BIT
Logic state
0
1
0
1
0
1
D
CLK
Q
A
B
PMVAL1 controls PWM1/PWM2 pair
PMVAL2 controls PWM1/PWM2 pair
PMVAL3 controls PWM3/PWM4 pair
PMVAL4 controls PWM3/PWM4 pair
PMVAL5 controls PWM5/PWM6 pair
PMVAL6 controls PWM5/PWM6 pair
Figure 9-21
A/B
GENERATOR
DEADTIME
Output control
shows motor voltage
MC68HC708MP16
Freescale Semiconductor
BOTTOM PWM
TOP PWM
—
Rev. 3.1