Sanyo VPC-E1W Service Manual

Contents

– 4 –Fig. 1-3. IC901 Block Diagram3. IC901 (V Driver)A V driver (IC901) is necessary in order to generate the clocks(vertical transfer clock and electronic shutter clock) whichdriver the CCD.In addition the XV1-XV13 signals which are output from IC101are vertical transfer clocks, and the XSG signal is superim-posed onto XV1, XV3 and XV5 at IC901 in order to generatea ternary pulse. In addition, the XSUB signal which is outputfrom IC101 is used as the sweep pulse for the electronic shut-ter.Fig. 1-4. IC905 Block Diagram4. IC905 (H Driver, CDS, AGC and A/D converter)IC905 contains the functions of H driver, CDS, AGC and A/Dconverter. As horizontal clock driver for CCD image sensor,H1, H2, H3, H4, HL and RG are generated inside, and outputto CCD.The video signal which is output from the CCD is input to pin(25) of IC905. There are sampling hold blocks generated fromthe SHP and SHD pulses, and it is here that CDS (correlateddouble sampling) is carried out.After passing through the CDS circuit, the signal passesthrough the VGA (VGA: Variable Gain Amplifier). It is con-verted internally into a small-amplitude actuating signal(LVDS), and is then input to IC101. The gain of the VGA am-plifier is controlled by pins (32), (33) and (34) using serialsignals which is output from IC101.1332333130373835363442434439404142613141211SUBCNTVDCCH1V1V6V4V5RV5LV3RV3LV1SCH5V5CH3CH4V3CH2GNDVHOV3BOV3AOV5BOV5ALevelconversion29V22 SUBLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversionLevelconversion28RESET20OV18VM21OV623OV424OV227VL10OSUB9VMSUB5VL2-level2-level2-level3-level2519171518VMOV1SOV3LOV3ROV5L716 OV5RVHH6 VH2-level2-level2-level2-level2-level3-level3-level3-level3-level3-levelCCDINHLH1 TO H4HDSDATASCKSLREFBREFTPRECISIONTIMINGGENERATORSYNCGENERATORVGA 12-BITADC6~42 dBVREFCLAMPINTERNALREGISTERSINTERNALCLOCKSCDSHORIZONTALDRIVERS4AD9971-3, 0, +3, +6dBVD CLIRGGP013V INPUT1.8V OUTPUTLDOREGGP02TCLKPREDUCEDRANGELVDSOUTPUTTCLKNDOUT0PDOUT0NDOUT1PDOUT1N