C-2C digital-to-analogue Converter on Insulator

Abstract

A new C-2C digital-to-analogue converter (DAC) as been investigated, which uses C and 2C capacitors. It is difficult to realise the C-2C DAC scheme on a silicon wafer because of the large parasitic capacitance. However, the C-2C DAC can be fabricated on glass or quartz substrates. The C-2C DACs require considerably less area and power than conventional weighted-capacitor (WC) DACs, and operate at a much higher conversion rate. Simulation results show that an 8 bit C-2C DAC can operate at a settling time of 5.3 ns for a unit capacitance of 1 pF.