Patent ID: 8797455
Filing Date: 2014-08-05
Classification: H03M,H04N

Abstract:
1. An analog-to-digital converter comprising: a signal processing unit generating an operational amplifier output voltage in response to an input voltage and a digital analog converter (DAC) output voltage in a sigma-delta operating period and generating the operational amplifier output voltage in response to a feedbacked operational amplifier output voltage and the DAC output voltage in a cyclic operating period; a control unit generating a DAC control signal by comparing the operational amplifier output voltage with a first reference voltage in the sigma-delta operating period and obtaining high order M-bits of data, and generating the DAC control signal by comparing the operational amplifier output voltage with second and third reference voltages in the cyclic operating period and obtaining low order N-bits of data; and a digital analog converter generating the DAC output voltage in response to the DAC control signal.