AN1917D Freescale Semiconductor / Motorola, AN1917D Datasheet - Page 3

• Manufacturer Part Number: AN1917D
• Description: 3-Phase PM Synchronous Motor Control with Quadrature Encoder Using DSP56F80x
• Manufacturer: Freescale Semiconductor / Motorola

MOTOROLA
The PM Synchronous motor control utilizes the PWM block set in the complementary PWM mode,
permitting generation of control signals for all switches of the power stage with inserted deadtime. The
PWM block generates three sinewave outputs mutually shifted by 120 degrees.
The Quad Timer is an extremely flexible module, providing all required services related to time
events. It has the following features:
The PM Synchronous motor application utilizes one channel of the Quad Timer module counting in
quadrature mode. It enables sensing of the rotor position using the Quadrature Encoder. The second
channel of the Quad Timer module is set to generate a time base for a speed controller.
The Quadrature Decoder is a module providing decoding of position signals from a Quadrature
Encoder mounted on a motor shaft. It has the following features:
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Features of complementary channel operation
Deadtime insertion
Separate top and bottom pulse width correction via current status inputs or software
Separate top and bottom polarity control
Edge-aligned or center-aligned PWM signals
15 bits of resolution
Half-cycle reload capability
Integral reload rates from 1 to 16
Individual software-controlled PWM outputs
Mask and Swap of PWM outputs
Programmable fault protection
Polarity control
20mA current sink capability on the PWM pins
Write-protectable registers
Each timer module consists of four 16-bit counters/timers
Count up/down
Counters are cascadable
Programmable count modulo
Max count rate equals peripheral clock/2 when counting external events
Max count rate equals peripheral clock when using internal clocks
Count once or repeatedly
Counters are preloadable
Counters can share available input pins
Each counter has a separate prescaler
Each counter has capture and compare capability
Logic to decode quadrature signals
Configurable digital filter for inputs
32-bit position counter
16-bit position difference counter
Maximum count frequency equals the peripheral clock rate
Position counter can be initialized by software or external events
Preloadable 16-bit revolution counter
Inputs can be connected to a general purpose timer to aid low speed velocity.
3-Phase PMSM Control with Quadrature Encoder
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
Motorola DSP Advantages and Features
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