PIPE-LINED CCD ANALOG-TO-DIGITAL CONVERTER

An analog-to-digital converter (ADC) uses pipe-lined data flow through parallelled charge transfer channels in a CCD for implementing a successive-approximation conversion algorithm. Successive charge splitting divides a standard level charge packet into binary-weighted charge packets, selectively added to develop the successive approximations against which charge packets dependent on analog input signal are differentially compared. These comparisons are made using floating gate sensors and auto-zeroed sense amplifiers. A battery of progressively shorter shift registers can convert the pipelined ADC output to parallel-bit form.