Download AC Induction Motor

Freescale Semiconductor, Inc.
Motorola DSP Advantages and Features
Freescale Semiconductor, Inc...
The PWM block has the following features:
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Three complementary PWM signal pairs, or six independent PWM signals
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Complementary channel operation
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Deadtime insertion
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Separate top and bottom pulse width correction via current status inputs or software
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Separate top and bottom polarity control
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Edge-aligned or center-aligned PWM signals
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15-bit resolution
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Half-cycle reload capability
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Integral reload rates from 1 to 16
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Individual software-controlled PWM output
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Programmable fault protection
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Polarity control
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20-mA current sink capability on PWM pins
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Write-protectable registers
The Analog-to-Digital Converter (ADC) consists of a digital control module and two analog sample
and hold (S/H) circuits. The ADC features:
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12-bit resolution
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Maximum ADC clock frequency of 5MHz with a 200ns period
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Single conversion time of 8.5 ADC clock cycles (8.5 x 200ns = 1.7µs)
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Additional conversion time of six ADC clock cycles (6 x 200ns = 1.2µs)
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Eight conversions in 26.5 ADC clock cycles (26.5 x 200ns = 5.3µs) using simultaneous mode
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ADC can be synchronized to the PWM via the SYNC signal
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Simultaneous or sequential sampling
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Internal multiplexer to select two of eight inputs
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Ability to sequentially scan and store up to eight measurements
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Ability to simultaneously sample and hold two inputs
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Optional interrupts at end of scan if an out-of-range limit is exceeded or at zero crossing
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Optional sample correction by subtracting a pre-programmed offset value
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Signed or unsigned result
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Single-ended or differential inputs
The application utilizes the ADC block in simultaneous mode and sequential scan. It is synchronized
with PWM pulses. Such a configuration allows conversion of the desired analog values of all phase
currents, voltage and temperature at once in the desired time.
MOTOROLA
3-Phase AC Induction Motor Vector Control
For More Information On This Product,
Go to: www.freescale.com
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