DSP56F803EVM Freescale Semiconductor, DSP56F803EVM Datasheet - Page 33

• Manufacturer Part Number: DSP56F803EVM
• Description: KIT EVALUATION FOR DSP56F803
• Manufacturer: Freescale Semiconductor

Specifications of DSP56F803EVM

• Processor To Be Evaluated: 56F803
• Data Bus Width: 16 bit
• Interface Type: RS-232, JTAG
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

2.16 Quadrature Encoder/Hall-Effect Interface
The 56F803EVM board contains a Quadrature Encoder/Hall-Effect interface connected to the
device’s Quad Encoder input port. The circuit is designed to accept +3.0V to +5.0V encoder or
Hall-Effect sensor inputs. Input noise filtering is supplied on the input path for the Quadrature
Encoder/Hall-Effect interface, along with additional noise rejection circuitry inside the
controller.
2.17 Zero-Crossing Detection
An attached UNI-3 motor drive board contains logic that can send out pulses when the phase
voltage of an attached 3-phase motor drops to zero. The motor drive board circuits generate a 0 to
+3.3V DC pulse via voltage comparators. The resulting pulse signals are sent to a set of jumper
blocks shared with the Encoder/Hall-Effect interface. The jumper blocks allow the selection of
Zero-Crossing signals or Quadrature Encoder/Hall-Effect signals. When in operation, the
controller will only monitor one set of signals, either the Encoder/Hall-Effect or the
Zero-Crossing.
Freescale Semiconductor
ZERO_X_A
ZERO_X_C
ZERO_X_B
PIN 1: +5.0V
PIN 2: GROUND
PIN 3: PHASE A
PIN 4: PHASE B
PIN 5: INDEX
PIN 6: HOME
J2
Figure 2-13
1
2
3
4
5
6
+5.0V
Figure 2-13
Figure 2-13. Zero-Crossing Encoder Interface
shows the encoder interface.
shows the Zero-Crossing and Encoder/Hall circuits.
FILTER
FILTER
FILTER
FILTER
Technical Summary, Rev. 5
JG7
1
9
3
4
6
7
2
5
8
Zero-Crossing Detection
HOME
PHASEA
PHASEB
INDEX
56F803
2-17