AN2514 Freescale Semiconductor / Motorola, AN2514 Datasheet - Page 15

• Manufacturer Part Number: AN2514
• Description: 3-Phase Sine Wave Generator TPU Function Set
• Manufacturer: Freescale Semiconductor / Motorola

Minimum Pulse Width
MOTOROLA
Phase A
Phase B
Phase C
- bottom
- bottom
- bottom
- top
- top
- top
HSR = 10
INIT
Figure 4. 3Sin_top and 3Sin_bottom state diagram
The TPU cannot generate PWM signals with duty cycle ratios very close to 0%
or 100%. The minimum pulse width that the TPU can be guaranteed to correctly
generate is determined by the TPU function itself and by the activity on the
other channels. When the TPU function is requested to generate a narrower
pulse, a collision can occur. To prevent this, the parameter MPW (minimum
pulse width) is introduced. The TPU functions 3Sin_top and 3Sin_bottom limit
the narrowest generated pulse widths to MPW. The CPU program should
check, and limit, the maximum amplitude of the Stator Reference Voltage
Vector. The maximum amplitude of the Stator Reference Voltage Vector should
be less than
If this is not the case, the TPU function will start to limit the minimum pulse
widths to MPW to prevent a collision, and the duty cycle ratio traces will be
deformed as shown on
3-Phase Sine Wave Generator TPU Function Set (3Sin)
Freescale Semiconductor, Inc.
flag0 = 1
For More Information On This Product,
flag0 = 1
flag0 = 1
flag0 = 0
Go to: www.freescale.com
Figure
LH_RLD
1
no reload
5.
( 2
reload
MPW
C123456
C23456
T
HL
LH
4-times
5-times
DT
5
th
-time
6
)
th
-time
LH_C7
HL
Detailed Function Description
HSR = 11
STOP
AN2514/D
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