Analogue-to-digital converter and method for using the same

摘要

The present invention is related to an analogue-to-digital (A/D) converter (1) for converting an input signal (V in ) to a digital code representing said input signal. The A/D converter comprises a comparator (3) for comparing the input signal with a reference signal (V A ), a search logic block (4) for determining the digital code and a digital-to-analogue converter (5) arranged for receiving input from the search logic block and for providing the reference signal to be applied to the comparator. The digital-to-analogue converter comprises at least a first portion implemented with equal capacitors (20). The ADC optionally further comprises a second portion implemented with binary weighted capacitors. The first portion is arranged for being controlled by a thermometer coded signal. The converter avoids charging-discharging of large capacitors during the search and therefore reduces the lost energy.