NuMicro® NUC029LEE/NUC029SEE
32-bit Arm
®
Cortex
®
-M0 Microcontroller
Aug, 2018
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Rev 1.00
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PWM
Waveform
write a nonzero number to
prescaler & setup clock
dividor
Start
Write
CNR=150
CMR=50
151
51
200
50
Write
CNR=199
CMR=49
Write
CNR=99
CMR=0
100
1
Write
CNR=0
CMR=XX
Stop
Figure 6.9-12 PWM Double Buffering Illustration
6.9.5.5 Modulate Duty Ratio
The double buffering function allows CMRn written at any point in current cycle. The loaded value
will take effect from next cycle.
Modulate PWM controller ouput duty ratio (CNR = 150)
Write
CMR=100
Write
CMR=50
Write
CMR=0
1 PWM cycle = 151
1 PWM cycle = 151
1 PWM cycle = 151
101
51
1
Figure 6.9-13 PWM Controller Output Duty Ratio
6.9.5.6 Dead-Zone Generator
The PWM controller is implemented with Dead-zone generator. They are built for power device
protection. This function generates a programmable time gap to delay PWM rising output. User
can program DZIxx (PPR[31:16]) to determine the Dead-zone interval.