AN2514 Freescale Semiconductor / Motorola, AN2514 Datasheet - Page 13

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

Performance
MOTOROLA
The maximum PWM frequency is 32kHz (PWM period T = 625 at 20MHz TCR1
clock). This can be achieved when only 3Sin_top and 3Sin_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 state lengths, including the time slot transition.
Convert the result from IMB clock cycles to TCR1 clock cycles according to
TCR1 prescaler settings. The result then indicates how much greater than its
minimum value of 625, T has to be for the particular case.
3-Phase Sine Wave Generator TPU Function Set (3Sin)
LD_OK
fault_pinstate
Theta_buf
Other parameters are just for TPU function inner use.
Freescale Semiconductor, Inc.
For More Information On This Product,
Parameter
Table 8. 3Sin_top and 3Sin_bottom parameter description
LH_C7
State
HL
Go to: www.freescale.com
Parameters written by both TPU and CPU
Table 9. 3Sin_top State Statistics
16-bit unsigned integer
0 or 1
32-bit fractional
Parameters written by TPU
Max IMB Clock Cycles
Format
32
2
0 ...... CPU can update
<>0 .. TPU can read variables:
CPU sets $0001 or $8001, TPU
If fault channel is used, state of
Actual Stator Reference Voltage
variables
$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
RAM Accesses by TPU
°
, 180
Detailed Function Description
Description
and prescaler only
°
)
10
1
AN2514/D
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