High resolution, high speed, low power switched capacitor analog to digital converter

摘要

A switched capacitor digital to analog converter includes first and second converter segments having respective first and second arrays of binary weighted capacitors. Each capacitor of the first segment has a first electrode connected to a first common node and a second electrode connected through respective switches to one of first and second reference voltage terminals. Each capacitor of the second segment has a first electrode connected to a second common node and a second electrode connected through respective switches to one of the first and second reference voltage terminals. The converter includes a coupling capacitor connected between the first and second common nodes and capacitance means connected between the first common node and a reference voltage terminal. The coupling capacitor and capacitance means have capacitances, Cs and CATT respectively, that substantially satisfy the relationship: (2<p>-1).Cs-CATT=2<p>.C, where p is the number of bits coded in the first converter segment and C is the unit capacitance.