WM8199 Datasheet | Wolfson Microelectronics plc

DESCRIPTION The WM8199 is a 16-bit analogue front end/digitiser IC which processes and digitises the analogue output signals from CCD sensors or Contact Image Sensors (CIS) at pixel sample rates of up to 20MSPS. The device includes three analogue signal processing channels each of which contains Reset Level Clamping, Correlated Double Sampling and Programmable Gain and Offset adjust functions. Three multiplexers allow single channel processing. The output from each of these channels is time multiplexed into a single high-speed 16-bit Analogue to Digital Converter. The digital output data is available in 8 or 4-bit wide multiplexed format. An internal 4-bit DAC is supplied for internal reference level generation. This may be used during CDS to reference CIS signals or during Reset Level Clamping to clamp CCD signals. An external reference level may also be supplied. ADC references are generated internally, ensuring optimum performance from the device. Using an analogue supply voltage of 5V and a digital interface supply of either 5V or 3.3V, the WM8199 typically only consumes 358m W when operating from a single 5V supply. FEATURES - - - - - - - - - - - - - - 16-bit ADC 20MSPS conversion rate 30MSPS conversion rate at 8-bits Low power - 358m W typical 5V single supply or 5V/3.3V dual supply operation Single or 3 channel operation Correlated double sampling Programmable gain (8-bit resolution) Programmable offset adjust (8-bit resolution) Programmable clamp voltage 8 or 4-bit wide multiplexed data output formats Internally generated voltage references 28-pin SSOP package Serial control interface APPLICATIONS - - - - Flatbed and sheetfeed scanners USB patible scanners Multi-function peripherals High-performance CCD sensor interface BLOCK DIAGRAM VRLC/VBIAS VSMP MCLK AVDD DVDD1 DVDD2 VRT VRX VRB w CL RS VS TIMING CONTROL R G B M U X 8 VREF/BIAS OFFSET DAC + PGA OEB + I/P SIGNAL POLARITY ADJUST M U X 16BIT ADC DATA I/O PORT OP[0] OP[1] OP[2] OP[3] OP[4]...