Philips CARDIOMD, Руководство по обслуживанию

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Detailed Description
1MAN0158-H11 04-2005 CSIP Level 1
CardioMD Service Manual
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3-27
3.3.4.1 Detector Power Supply
The detector power supply receives the 55 V DC power through the detector cable. The 55 V are
used to generate 4 low voltages: +15 V, +5 V, –5 V, –15 V and a negative high voltage adjustable
to – 1500 V max.
A separate 55 V supply is transferred through the detector power supply to the EDC boards for
their power requirements.
The master EDC board (located on detector 1) controls the high voltage, which is common to both
detectors, and it receives diagnostic information from the detector power supply.
3.3.4.2 EDC Board
The Event Digitization and Correction – EDC – Board is the intelligent core of the detectors. It
handles a number of tasks:
•
It handles all FireWire communication between the acquisition PC and the gantry.
•
It (the master EDC board) handles the communication between the FireWire from the PC and
the CANbus to the motion controllers.
•
It (the master EDC board) controls the high voltage and reads diagnostic information from the
detector power supply unit.
•
It writes tuning values to the tune DAC’s and drives the autotune circuits.
•
It writes gain values to the control DAC’s for DynCor and threshold.
•
It reads PMT working point values from the PMT’s.
•
It synchronizes gated acquisitions with external ECG monitor.
•
It detects collision on collimator and detector and reads the collimator ID.
•
It reads the ID code specific for the individual detectors.
•
It digitizes the four position signals and the Energy signal from the X-E strip (X+, X– and
Energy) and the Y strip (Y+ and Y–).
•
It applies spatial and energy corrections based on downloaded tables.
3.3.5 Detector/Collimator ID Boards
On the detector front, facing the collimator is a small board with five spring contacts. The detector
ID EEPROM is located on the backside of that detector/collimator ID board. The board also
serves as interface to a similar board with spring contacts on the collimators. The boards on the
collimators carry the collimator ID EEPROM.