AN2517 Freescale Semiconductor / Motorola, AN2517 Datasheet - Page 13

• Manufacturer Part Number: AN2517
• Description: 3-Phase Sine Wave Generator with Dead-Time Correction TPU Function Set
• Manufacturer: Freescale Semiconductor / Motorola

Performance
MOTOROLA 3-Phase Sine Wave Generator with Dead-Time Correction TPU Function Set (3SinDt)
The maximum PWM frequency is 32kHz (PWM period T = 625). This can be
achieved when only 3SinDt_top and 3SinDt_bottom run on the TPU and the
IMB clock is 40MHz. When other functions run on the same TPU the minimum
PWM period T has to be greater. Get all the other enabled function states that
can be served during one PWM period. Get their lengths (number of IMB clock
cycles) and add a time slot transition of 10 IMB clock cycles to each one. Sum
all the states lengths including the time slot transition. Convert the result from
IMB clock cycles to TCR1 clock cycles according to TCR1 prescaler settings.
The result indicates how much greater than the minimum value of 625, T has
to be for that particular case.
sync_presc_addr
LD_OK
fault_pinstate
Theta_buf
Other parameters are just for TPU function inner use.
Freescale Semiconductor, Inc.
For More Information On This Product,
Table 8. 3SinDt_top and 3SinDt_bottom parameter description
Parameter
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Parameters written by both TPU and CPU
8-bit unsigned integer
16-bit unsigned integer
0 or 1
32-bit fractional
Parameters written by TPU
Format
address of synchronization
$0 if no synchronization channel
0 ...... CPU can update variables
<>0 .. TPU can read variables:
CPU sets $0001 or $8001, TPU
If fault channel is used, state of
Actual Stator Reference Voltage
channel prescaler parameter:
$X4,
where X is synchronization
channel number.
is used.
$0001 ... load Ampl, dTheta, T
$8001 ... load also Theta
sets 0
fault pin:
0 ... low
1 ... high
Vector angle
range <–1, 1) corresponds to
<–180
°
, 180
Detailed Function Description
Description
and prescaler only
°
)
AN2517/D
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