PETAL: A Multichannel Differential ADC Driver for High-Speed CMOS Image Sensors

Programmable Electronic Termination and Line Driver (PETAL) is a 16-channel ADC driver chip that provides single-ended-to-differential conversion and column biasing for high-speed CMOS image sensors. By increasing the level of integration, the number of driver chips and the associated number of passives and the routing area are reduced, enabling smaller physical cameras. Power dissipation is reduced relative to many commercial approaches by the use of low-voltage CMOS technology and the increased level of integration. The driver chip also supplies programmable bias currents to the sensor, further reducing the number of required components on the camera board. The driver, fabricated in 180-nm CMOS technology, achieves settling to 0.1% in 11 ns with input noise of 89.9-mu V rms. The crosstalk between channels is below -56 dB. The power dissipation is 10.5 mW/channel. When applied to the readout of a high-speed X-ray sensor, the prototype reduced board area by 84% (from 100 to 16 mm(2)) and power dissipation by 25%.