Hologic DISCOVERY A, Technical Manual

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Discovery QDR Series Technical Manual
1-7
Figure 1-6.Discovery Distribution and Motor Control Block Diagram
The heart of the Discovery Scanner is the Distribution Board. This board interfaces the PC
to the different subsections of the Scanner, distributes control signals to the table and C-
Arm, and distributes DC power throughout the Scanner. The Distribution Board receives
command inputs from the PCI Communications Controller Board in the PC and voltages
from the DIN rail and Low Voltage Power Supply. Commands and voltages dealing with
the generation of X-Rays or the acquisition of scan data are transferred to the C-Arm
Interface Board, which controls both functions. The Distribution Board also receives
Table and C-Arm motion commands from the PCI Communications Controller Board in
the PC.
When a motion command is received, the Distribution Board routes the command along
with a board address to the Motor Driver Boards. The addressed Motor Driver Board
converts these digital commands into analog signals that are strong enough to drive the
motors. A Position Encoder attached to the idler pulley moved by the motor, senses
changes in the position of the arm or table. This device provides a voltage feedback to the
Motor Driver Board that is translated into a motor position, which in turn, is fed back to
software in the Operator’s Console PC.
The Discovery Control Panel is located at the head end of the table and communicates
with the Distribution Board via the Control Panel Interface Board. The Control Panel
provides the operator with a means to issue manual commands to move table and arm
TY Stepper
Motor Driver
TX Stepper
Motor Driver
AY Stepper
Motor Driver
TY
Motor
TY
Encdr
TX
Motor
TX
Encdr
AY
Motor
AY
Encdr
Signal
Distribution
Board
To/From C-Arm Interface
To/From Control Panel Interface
To/From
Communications
Controller
+/-15V
JP1
+24V
From DIN
Rail
and LVPS
AR Stepper
Motor Driver
AR
Motor
AR
Encdr
TZ Stepper
Motor Driver
TZ
Motors
TZ
Encdrs
AC
JP4
JP5
JP7
JP11
JP8
JP6
JP10