Hologic QDR 4500 - Data Acquisition System Components

QDR
®
4500 Technical Manual
2-26
X-RAY SOURCE UNIT
The X-Ray Source (commonly referred to as the Tank assembly) consists of the X-Ray tube, the
X-Ray tube filament transformer, the high voltage transformer, the high voltage rectifier circuit,
and the sensing circuits that monitor the high voltage applied to the X-ray tube and the beam
current.
Table 2-20 describes the interconnections between the X-Ray Controller Assembly and the X-
Ray Source unit. The table also identifies the X-Ray Controller Assembly board, connector and
pin assignments for each interconnection signal.
Table 2-20. X-Ray Controller Assembly/X-Ray Source Unit Interface
Signal Description XRC Board Controller
Pin
Tank
Terminal
HV_XFMR_PRI+
HV_XFMR_PRI-
High Voltage Transformer
Primary
H-Bridge
(JP1)
JP1-1, JP1-2
JP1-3, JP1-4
TB1-3
TB1-4
FIL_XFMR_A
FIL_XFMR_B
Filament Transformer
Primary
I/O & Logic
(JP6)
JP2-7
JP2-8
TB1-6*
TB1-9
IF+ Beam Current Sense "+" I/O & Logic
(JP6)
JP2-4 TB1-10
IF- Beam Current Sense "-"
(Chassis)
I/O & Logic
(JP6)
JP2-5 TB1-7
TP1 Anode pulse monitor I/O & Logic
(JP6)
JP2-2 TB1-12
TP2 Cathode pulse monitor I/O & Logic
(JP6)
JP2-1 TB1-11
* A thermal overload protector is installed in series with the filament transformer primary
winding, between TB1-6 and TB1-8.
DATA ACQUISITION SYSTEM
The QDR 4500 Data Acquisition System (DAS) consists of three Solid State Detector printed
circuit boards, an Integrator/Multiplexor board, and an Analog To Digital Converter (ADC)
board. The Solid State Detector boards and the Integrator/Multiplexor board are physically
located within the upper end of the C-arm. The detector boards mount under the
Integrator/Multiplexor board and connect to the Integrator/Multiplexor board. The
Integrator/Multiplexor board is contained in an electrically shielded enclosure. There is also a
lead radiation shield between the detector and the integrator/multiplexor boards to stop any X-
rays that might get through the detectors. The ADC board is located within the rear downward
slope of the C-arm.