Exar XRD9827REF, User Manual

Page 1: ...XRD9827REF USER MANUAL CANNON CIS 36 BIT COLOR SINGLE LINE SCANNER ...

Page 2: ... CIS with EXAR s XRD9827 a 12 bit Linear CIS CCD Sensor Signal Processor to output a single line scan and display the amplitude of each of the three colors The XRD9827REF is designed to provide a signal path for the CIS output signals to be processed digitized by the XRD9827 and transmitted to a personal computer There are no software algorithms or hardware implementations for example gamma correc...

Page 3: ...RD9827REF The XRD9827 is a complete linear CIS or CCD sensor signal processor on a single monolithic chip The XRD9827 includes a high speed 12 Bit ADC a 6 Bit Programmable Gain Amplifier with gain adjustment of 1 to 10 and an 8 Bit programmable input referred offset calibration range of 800 mV The XRD9827 also provides the necessary biasing voltage for the CANON CIS eliminating the use of external...

Page 4: ...ET REGISTERS 6 8 _ AGND V DCREF DC AC INT EXT_V DCREF CIS CCD G 5 0 O 7 0 R G B R G B CLP CLAMP Power Down Power Down VRT CCD CIS VBG Biasing Circuit for CANON CIS Figure 2 Simplified Functional Block Diagram of XRD9827 OPERATIONAL PROCEDURE The routine listed below will first calibrate the photo response of the CIS using the XRD9827 by optimize its offset and gain After calibration the XRD9827REF...

Page 5: ...k on Printer Port LPT1 If you can not find it please goto Step 10 VI From the pop up window select Resources VII Verify the Input Output Range is set to 0378 037F VIII If the range is not correct clear the Use Automatic Settings check box by clicking it IX Choose correct address which is 0378 by default and click OK X Re start the computer as advised 10 If you do not have a Printer Port configured...

Page 6: ... 7 D 6 D 2 D 1 D 3 D 0 Figure 3 Dip Switches Set to Value 110 01000000 to Reset XRD9827 12 Select the Start Menu choose Programs then choose SenseIt icon 13 A window will pop up as shown below The upper window shows the plot of captured data and the lower window shows the histogram of data Figure 4 shows the pop up window when SenseIt is first started ...

Page 7: ...e in the Input Output Range of Printer Port of your computer The default setting is 378H 15 Pick the black target out from the kit and put it on a flat area Place the XRD9827REF on top of the black target with the CIS sensor facing downwards From the CAPTURE menu select SNAP SHOT or simply press CTRL and B buttons simultaneously for a single line scan of the black target with the dip switches set ...

Page 8: ...can 16 Set the dip switches to 110 00010000 to tie VDCREF and VDCEXT pin together internally Push the Serial Port button The XRD9827 will subtract whatever voltage appears on VDCEXT pin 16 from the input and thus perform a global offset adjustment A typical result of the global offset adjustment is shown below Please notice that the black code value has moved down ...

Page 9: ...10000 and push the Serial Port button again By doing this a 1 24V reference voltage provided by an internal bandgap is applied to the VDCEXT pin VDCEXT is connected to VREF pin Pin 5 of the CANON CIS this voltage is used by the CIS as a biasing voltage Moreover a 12K built in resistor of the XRD9827 serves as a pull down for the output of the CIS By interfacing the XRD9827 with a CANON CIS a desig...

Page 10: ...7 Using Internal Bandgap and CIS Using VDCEXT for Biasing 18 Set the dip switches to 001 01010000 to select the internal offset DAC for fine offset adjustment Push the Serial Port button From the CAPTURE menu select SNAP SHOT The offset should now move the output of the CIS to almost zero scale The other way to do a SNAP SHOT is by pressing CTRL and B button at the same time Please refer to data s...

Page 11: ... the analog plus compa TM EXAR Corporation 48720 Kato Road Fremont CA 94538 Phone 510 668 7000 Fax 510 668 7030 PRELIMINARY 11 Figure 8 Black Target Scan After Global and Fine Adjustment ...

Page 12: ... RL VRT VRB VDD PIN 19 RED XRD9827 C I S 8 BIT OFFSET DAC M U X Figure 9 Simplified Block Diagram Showing Fine Offset Adjustment by XRD9827 19 Switch the black target to the enclosed white target From the CAPTURE menu select SNAP SHOT for a single line scan of the white target A typical result of a white target is shown below ...

Page 13: ...t 20 Set the dip switches to 000 00001000 to select the desired gain Push the Serial Port button From the CAPTURE menu select SNAP SHOT The gain should move the output of the CIS to almost full scale Please refer to data sheet for further gain adjustment and optimal values of dip switches for your scanner A typical result of the white target with gain adjustment is shown below ...

Page 14: ... the analog plus compa TM EXAR Corporation 48720 Kato Road Fremont CA 94538 Phone 510 668 7000 Fax 510 668 7030 PRELIMINARY 14 Figure 11 White Target Scan After Gain Adjustment ...

Page 15: ...15 PIN 19 RED XRD9827 C I S RL VRT VRB VDD PGA 6 BIT GAIN REGISTER M U X Figure 12 Simplified Block Diagram Showing Gain Adjustment by XRD9827 21 Once the XRD9827 has been fully calibrated any target can be scanned For example Scan a gray scale to demonstrate the stair step response or a color target for color responsitivity ...

Page 16: ...D DEVIATION SYSTEM SNR dB W O CIS NOISE COMPONENT 2 0 2 144328 62 6117 2 5 3 48261 58 3988 3 0 2 399188 61 6356 3 5 1 983461 63 28842 Table 1 Signal to Noise Ratio of the XRD9827REF with DC Source as Input No CIS Noise Component As we can see from Table 1 the SNR falls into the range of 58 dB to 63 dB when a DC reference is used as input to the XRD9827REF The system alone gives a 9 1 2 to 10 bit p...

Page 17: ...the demo system seems to not working please pull the AC adapter out from the wall outlet to cycle power Start the procedures again from Step 11 2 Keep the scanner away from other electrical equipment power cords light dimmers etc as stray electrical fields can end up in the digitized data 3 Switch off all unnesscessary light sources and place the scanner flat on the image this can prevent stray li...

Page 18: ...GND DGND CISOUT DB7 LD DB6 SDATA DB5 SCLK DB2 DB3 DB4 DB0 DB1 ADCCLK VDCEXT SYNC POWER SUPPLY CIRCUITS GO TO LED ON THE CASE OF SCANNER C1 0 1uF C2 0 01uF L1 10uH U2 LM7805 5 IN 1 OUT 3 GND 2 U3 LM7805 5 IN 1 OUT 3 GND 2 C4 0 1uF C3 1uF TP1 t 1 g 2 C8 0 22uF C9 0 1uF C10 0 22uF C11 0 47uF J1 POWERJACK JP1 HEADER 2 1 2 R3 1K U1 XRD9827 DVDD 1 DB0 2 DB1 3 DB2 4 DB3 5 DB4 6 DB5 SCLK 7 DB6 SDATA 8 DB7...

Page 19: ...2 2K R14 2 2K R15 2 2K R16 2 2K R17 2 2K R18 2 2K C19 0 01uF C20 0 01uF C13 0 1uF C12 1uF JP2 HEADER 3 1 2 3 S1 SW DIP 12 1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 19 20 21 22 23 24 R8 2 2K MACH435 U4 MACH435 DVDD1 2 DVDD2 21 DVDD3 42 DVDD4 44 DVDD5 63 DVDD6 84 DGND1 1 DGND2 11 DGND3 22 DGND4 32 DGND5 43 DGND6 53 DGND7 64 DGND8 74 CLK0 20 CLK1 23 I1 41 CLK2 62 CLK3 65 I2 83 IO0 3 IO1 4 IO2 5 IO...

Page 20: ... 7 0 J2 DB25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 R24 300 R26 300 R28 10K R29 10K R30 10K C25 0 1uF C26 0 01uF C27 0 01uF JP4 HEADER 12 TO CIS 1 2 3 4 5 6 7 8 9 10 11 12 C23 10uF C30 47uF C31 0 1uF U7B 74HC04 3 4 U7C 74HC04 5 6 U7D 74HC04 9 8 U7F 74HC04 13 12 14 7 U7E 74HC04 11 10 U7A 74HC04 1 2 U6 CY7C4261 D5 1 D4 2 D3 3 D2 4 D1 5 D0 6 PAF 7 PAE 8 GND 9 REN1 10 RCLK 1...