Wolfson Microelectronics has extended its range of Analogue Front End (AFE) chips to target the flatbed scanner, multi-function peripheral and digital photocopier markets.
Its latest new product, the WM8150, is a 20-pin single channel 12 bit CIS/CCD AFE with 4 bit wide output.
Offering the complete signal path between sensor and digital processor, the AFE is designed to work with either CIS or CCD sensors at a pixel sample rate of up to 8MSPS.
The signal path includes Reset Level Clamping, Correlated Double Sampling, Programmable Gain and Offset Adjust functions. The Offset DAC and the Programmable Gain amplifier can each be switched to different values using on chip registers and multiplexers to facilitate the processing of line by line RGB colour information.
The Programmable Gain Amplifier is monotonic over its 8 bit range, and gives input voltage range from 0.3V for full scale digital output at max gain to 3.22V for full scale digital output at minimum gain. Overall DNL is typically 0.5LSB and INL is typically 2LSB.
The device uses either a single 5V supply rail, or a 5V analogue supply and a digital interface supply of either 5V or 3.3V. Current consumption is 45mA max, but power down modes offer 1mA operation with all analogue functions off, and 300microAmp in full power down mode.
The WM8150 is currently available in a 20-lead SSOP package. The WM8150 is priced from $1.15 in 10k quantities.