Patent ID: 7372389

Claim:
An analogue to digital converter comprising: a dual differential digital to analogue converter (DAC) having first and second digital inputs for first and second digital input signals, respectively, and having first and second analogue differential output for first and second differential output signals respectively, where the first and second differential output signals are associated with the first and second digital inputs respectively; storage for storing a DAC digital input value; logic for deriving the first and second digital input signals from the DAC digital input value, such that the difference between the first and second differential output signals from the DAC represents the DAC digital input value; a comparator for comparing the first and second differential output signals from the DAC with an analogue input signal and providing a comparator output; and a controller, responsive to the comparator output, for modifying the DAC digital input value such that the DAC digital input value substantially represents the analogue input signal.