Patent ID: 9007252
Filing Date: 2015-04-14
Classification: H03M

Abstract:
1. An analog to digital (A/D) conversion method, comprising: charging a capacitor through an analog signal to sample a voltage of the analog signal; coupling the capacitor and a plurality of reference voltages to a comparator when a voltage of the capacitor is equal to the voltage of the analog signal, to compare the voltage of the capacitor with the plurality of reference voltages and generate a first comparison result; coupling the capacitor to a ramp generator when a status of the first comparison result changes, to compare a ramp signal of the ramp generator with a voltage difference of a first reference voltage of the plurality of reference voltages and the voltage of the capacitor and generate a second comparison result; obtaining a first voltage of the ramp signal when a status of the second comparison result changes; and obtaining a digital code of the analog signal according to the first reference voltage and the first voltage of the ramp signal.