WM8259 w Single Channel 16-bit CIS/CCD AFE with 4-bit Wide Output DESCRIPTION FEATURES 16-bit ADC The WM8259 is a 16-bit analogue front end/digitiser IC which processes and digitises the analogue output signals 3MSPS conversion rate from CCD sensors or Contact Image Sensors (CIS) at pixel Low power - 132mW typical sample rates of up to 3MSPS. 3.3V single supply or 3.3V/2.5V dual supply operation The device has two selectable video input pins and one Single channel operation, selectable inputs complete analogue signal processing channel containing Correlated double sampling Reset Level Clamping, Correlated Double Sampling, Programmable gain (8-bit resolution) Programmable Gain and Offset adjust functions. Internal Programmable offset adjust (8-bit resolution) multiplexers allow fast switching of offset and gain for line- Programmable clamp voltage by-line colour processing. The output from this channel is time multiplexed into a high-speed 16-bit Analogue to Digital 4-bit wide multiplexed data output format Converter. The digital output data is available in 4-bit wide Internally generated voltage references multiplexed format. 20-lead SSOP package An internal 4-bit DAC is supplied for internal reference level Serial control interface generation. This may be used during CDS to reference CIS signals or during Reset Level Clamping to clamp CCD APPLICATIONS signals. An external reference level may also be supplied. Flatbed and sheetfeed scanners ADC references are generated internally, ensuring optimum performance from the device. USB compatible scanners Multi-function peripherals The device uses an analogue supply voltage of 3.3V and a High-performance CCD sensor interface digital interface supply of between 2.5V and 3.3V. The WM8259 typically only consumes 132mW when operating from a single 3.3V supply. BLOCK DIAGRAM WOLFSON MICROELECTRONICS plc Production Data, April 2007, Rev 4.2 To receive regular email updates, sign up at WM8259 Production Data TABLE OF CONTENTS DESCRIPTION .......................................................................................................1 FEATURES.............................................................................................................1 APPLICATIONS .....................................................................................................1 BLOCK DIAGRAM .................................................................................................1 PIN CONFIGURATION...........................................................................................3 ORDERING INFORMATION ..................................................................................3 PIN DESCRIPTION ................................................................................................4 ABSOLUTE MAXIMUM RATINGS.........................................................................5 RECOMMENDED OPERATING CONDITIONS .....................................................5 ELECTRICAL CHARACTERISTICS ......................................................................6 INPUT VIDEO SAMPLING .....................................................................................8 OUTPUT DATA TIMING.........................................................................................9 SERIAL INTERFACE..............................................................................................9 DEVICE DESCRIPTION.......................................................................................10 INTRODUCTION ..................................................................................................10 INPUT SAMPLING ...............................................................................................10 RESET LEVEL CLAMPING (RLC) .......................................................................10 CDS/NON-CDS PROCESSING............................................................................11 OFFSET ADJUST AND PROGRAMMABLE GAIN...............................................12 ADC INPUT BLACK LEVEL ADJUST...................................................................13 OVERALL SIGNAL FLOW SUMMARY ................................................................13 CALCULATING OUTPUT FOR ANY GIVEN INPUT ............................................13 OUTPUT DATA FORMAT ....................................................................................14 CONTROL INTERFACE.......................................................................................15 TIMING REQUIREMENTS ...................................................................................15 PROGRAMMABLE VSMP DETECT CIRCUIT .....................................................16 REFERENCES .....................................................................................................17 POWER SUPPLY.................................................................................................17 POWER MANAGEMENT .....................................................................................17 OPERATING MODES ..........................................................................................17 OPERATING MODE TIMING DIAGRAMS ...........................................................18 DEVICE CONFIGURATION .................................................................................20 REGISTER MAP...................................................................................................20 REGISTER MAP DESCRIPTION .........................................................................21 RECOMMENDED EXTERNAL COMPONENTS ..................................................24 PACKAGE DIMENSIONS ....................................................................................25 IMPORTANT NOTICE ..........................................................................................26 ADDRESS: ...........................................................................................................26 PD Rev 4.2 April 2007 w 2