WM8259

w WM8259 Single Channel 16-bit CIS/CCD AFE with 4-bit Wide Output DESCRIPTION The WM8259 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 3MSPS. The device has two selectable video input pins and one complete analogue signal processing channel containing Reset Level Clamping, Correlated Double Sampling, Programmable Gain and Offset adjust functions. Internal multiplexers allow fast switching of offset and gain for lineby-line colour processing. The output from this channel is time multiplexed into a high-speed 16-bit Analogue to Digital Converter. The digital output data is available in 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. The device uses an analogue supply voltage of 3.3V and a 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 FEATURES 16-bit ADC 3MSPS conversion rate Low power - 132mW typical 3.3V single supply or 3.3V/2.5V dual supply operation Single channel operation, selectable inputs Correlated double sampling Programma...