检测器模块-英文

1、Philips and Neusoft Medical Systems Co.,LtdThe function of DAS: lMeasure the intensity of X-ray radiated from the tube and after though the patients body.lSupply the additional information for image reconstruction. lDetector: Convert the attenuated X-ray to current signal. lDAS board: Convert the cu

2、rrent signal from the detector to digital signal and store the DAS data temporarily. lMONITOR: Convert the current signal from monitor detector to digital signal. Measure the intensity of X-ray before its attenuation; and measure the focus of tubes swaying along Z-axislDAS Interface board: Transform

3、 the data from DAS-Board and monitor to set format; realize the communication between RCS and GCS. lChannel: A dimensional concept. The minimal unit in dimension of DAS. There are 1440(7202) channels in Competitive CT DAS.lVIEW: A temporal concept, each acquisition process is called one view. lDDC11

4、2: A dual input, charge-digitizing analog-to-digital converter (ADC) with 20-bit resolution. Sketch:l26LS32: Differential line receiver. Receive the control signal from DAS interface board.lDASFIFO: IDT7200（2569bit）. Store the data from each DAS board of every view. The FIFO in each DAS-Board cascad

5、es together by DAS motherboard. lVoltage Reference: OPA350UA. Supply a reference for DDC112, which is 4.096v.lISA Interface:Connect to the 32 analog outputs and the cathode of each detector module.lPCI Interface: Include power supply of DAS board, control signal and DASFIFO data signal.lThere are 16

6、 DDC112 in each DAS board, and the 32 input channels of each DAS board is connected with 32 outputs of the detector module. Every two DDC112 cascading together form a data output(DOUT) which connects to one input of DASFIFO. So there are 8 data chains(DAT1-DAT8). Each data chain includes 4 channels

7、data(80bits in total). lCONV: Control which side of the integrator is connected to input. In continuous mode; CONV HIGH side A is integrating, CONV LOW side B is integrating.lCONV must be synchronized with CLK.lRANG2-RANG0: Range control signal lRange Selection of the DDC112:lTo select range by Rang

8、e2Range0 is realized through the selection of different capacitor combination. lTEST: Test Control Input. When HIGH, a test charge(13pc) is applied to the A or B integrators on the next CONV transition. Sketch: lCLK: System Clock Input. 10Mhz in this system.lDCLK: Serial Data Clock Input. This input

9、 operates the serial I/O shift register. 10Mhz in this system.lDXMIT: Serial Data Transmit Enable Input. When LOW, this input enables the internal serial shift register.lDIN: Serial Digital Input. Used to cascade multiple DDC112s.lDOUT: Serial Data Output, Hi-Z when DXMIT is HIGH.l#DVALID: Data Vali

10、d Output. A LOW value indicates valid data is available in the serial I/O register.lWorking process of DDC112:The work of DDC112 consist of four processes:I: Reset II : IntegrateIII: Convert IV: data outputlReset: Range2-Range0 controls which capacitor connect to Vref which will charge till the volt

11、age is 4.096V. lIntegrate: the capacitor Cf discharge under the effect of the input. lConvert: after integrate ,the voltage is set to the converter which will generate a result of 20bits.lIn Competitive CT DAS, the work mode of DDC112 is continuous mode: A Side integrates while B Side converts; B Si

12、de integrates while A Side converts. lData Output: DDC112 stores the data in internal register after convert process, then it generates Dvalid signal that indicates the data is ready. Data will be output at DOUT at the falling edge of DCLK. lMonitor board is installed in the X-ray box under the tube

13、(the monitor detector is also installed in this box).The function of monitor board is similar to DAS board,but the analog signal is from monitor detector.Monitor board converts this signal to digital signal and sends it to DAS interface board. lThere is a DDC112 on the monitor board,which can proces

14、s two channel analog signal. The two analog signal come from monitor detectors A slice and B slice. The swaying that tube focus along Z-axis can be expressed by the value of A side and B side. lTemperature Detect Board is installed in the DAS box beside the detectors. The function of temperature boa

15、rd is to detect the temperature around the detector, and the result is send to DAS interface board. lThere three Temperature Detect Boards is each DAS box, which are cascaded together by I2c bus. lThe chip is AD7414. Function: Transform the data from DAS-Board, monitor and temperature detect board t

16、o set format, and realize the communication between RCS and GCS. RIGHT_CHIP: lOrganize the data from DAS-board,Monitor-Board,HV-board,Temperature Detect Board and form in the data frame that apply in communication. lStore the data in DATA_FIFO Format of data frame: 160016bit Communication frame head

17、（216bit）communication frame NO.(216bit）data frame head（16bit）couch code（16bit）time channel（16bit）view number（16bit）monitor1（16bit）monitor2（16bit）KV（16bit）MA（16bit）filament（16bit）pre-collimator（16bit）post-collimator（16bit）Reserve(16bit)tube-position（16bit）temperature（616bit）Reserve(8716bit) DAS data（

18、144016bit）CRC1（216bit）CRC2（216bit）Reserve（4616bit）LEFT_CHIP: lControl PLX9054 to implement PCI Bus function;lRealize communication with GCS;lGenerate control signal of DAS board, Monitor board, Temperature detect board ;lProcess the signal couch-code,view, zpoint.lDATA_FIFO: Store the data organized

19、 in the RIGHT_CHIP. lFRAME_FIFO: Store the data frame that is ready to send.DAS Interface: lDAT8-DAT1: 8 data chains. DAS Motherboard to DAS Interface Board.lDXMIT: Serial Data Transmit Enable. DAS Interface board to DAS Mother board. lSYSCLK: System Clock of DDC112 10MHz. DAS Interface board to DAS

20、 Mother board. lDATCLK: Serial Data Clock, 10MHz. DAS Interface board to DAS Mother board. lCONV: Control which side of the integrator is connected to input. DAS Interface board to DAS Mother board. lRANG2-RANG0: Range control signal, DAS Interface board to DAS Mother board. lTEST: Test Control Inpu

21、t, DAS Interface board to DAS Mother board. lDASRS: Reset signal of DASFIFO, DAS Interface board to DAS Mother board.lDASWR: Write signal of DASFIFO, DAS Interface board to DAS Mother board. lDASRD: Read signal of DASFIFO, DAS Interface board to DAS Mother board. Monitor Interface: lMDAT: Data from

22、Monitor board, Monitor board to DAS Interface board. lMDVALID: The Dvalid signal of DDC112 on the Monitor board. Monitor board to DAS Interface. lMRANG2-MRANG0: Range control signal of DDC112 on the Monitor board. DAS Interface board to Monitor board. lMTEST: Test Control Input of DDC112 on the Moni

23、tor board, DAS Interface board to Monitor board. lMCONV: Integrate control signal of DDC112 on the Monitor board. DAS Interface board to Monitor board. lMSYSCLK: System clock signal of DDC112 on the Monitor board. 10MHz DAS Interface board to Monitor board. lMDXMIT: Serial Data Transmit Enable of DD

24、C112 on the Monitor board. DAS Interface board to Monitor Board . lMDATCLK: Serial Data Clock of DDC112 on Monitor board, 10MHz DAS Interface board to Monitor board. lVCC: Power supply.lGND: Ground.Slip Ring Interface:lSCLK: Send data clock,DAS Interface board to slip ring to communication card.12.5

25、Mhz,double edges active. lSDATH: Serial sending data(15 downto 8), DAS Interface board to slip ring to communication card. lSDATL: Serial sending data(7 downto 0), DAS Interface board to slip ring to communication card. lRCLK: Receive data clock. Communication card to slip to DAS Interface board. 3.

26、125Mhz, double edges active. lRDAT: Receive data. Communication card to slip to DAS Interface board. lVIEW: Sample pulse. Encode tape to GCS Connecting board to slip ring to DAS Interface board. lZPOINT: Home pulse. Slip to DAS Interface board. lBCODE: Couch code signal . Movement control board to s

27、lip ring to DAS Interface board. HV Interface:lHV_STATE_CLK: Clock. DAS Interface board to HV&Collimator control board. 5MHz . For getting HV and collimator state. lHV_STATE_LCP: Latch signal. DAS Interface board to HV&Collimator control board. For updating the register of HV&Collimator

28、control board. lHV_STATE_DAT: Serial state data. HV&Collimator control board to DAS Interface board lKV(16BIT)+MA(16BIT)+FILAMENT(16BIT)+PRE-COLLIMATOR(16BIT)+POST-COLLIMATOR(16BIT) lVIEW: DAS Interface board to HV&Collimator control board. lZPOINT: DAS Interface board to HV&Collimator c

29、ontrol board. lCOUCH_CODE_CLK: Clock. DAS Interface board to HV&Collimator control board. 5MHz. For sending couch code and monitor data to HV&Collimator control board. lCOUCH_CODE_DAT: Serial data. DAS Interface board to HV&Collimator control board. Couch code(16bits) +monitor1(20bit) +m

30、onitor2(20bits). lCOUCH_CODE_LCP: Latch signal. DAS Interface board to HV&Collimator control board. For indicating the start point . Temperature Interface:lVCC: Power supply.lGND: Ground.lSCL: Clock signal of I2C bus.lSDA: Data signal of I2C bus.l Sample with equal angle . lThe max rotate speed

31、is 0.75s/rev.lThe output of each channel is 16bits float data. lThe data quantity of each view is 160016bits.The cause: The output of each channel of DDC112 is 20bits data, but while the computer processes 20bits data much resource be cost, moreover, the burden of the communication system will be in

32、creasing. So 20bits data should be transformed to 16 bits.Method of transform: Suppose D is 20bits DAS data, Q is 16bits float data. We will get the following relation: l If D=16383(HEX 3FFF) Q=“10” & D;l If 16383(HEX 3FFF) D131071(HEX 1FFFF) Q=“00” & D/64;Competitive CT has five scan modes:l pilo