SINGLE SLOPE ANALOG-TO-DIGITAL CONVERTER

摘要

A single-slope ADC, particularly suitable for use in a massive-parallel ADC architecture in a readout circuit of a CMOS imager. A plurality of ramp signals are generated which define non-overlapping sub-ranges of the full input range. For each ADC channel, the sub-range in which the voltage of the input signal falls is determined, and the corresponding ramp signal is selected for use in the A/D conversion. Thus, the speed of the A/D conversion process can be increased and the power consumption decreased.