Patent ID: 7675451
Filing Date: 2010-03-09
Classification: H03M

Abstract:
1. A serial-parallel type analog-to-digital converter comprising: a reference voltage generator configured to generate a plurality of different reference voltages; a higher bit comparing portion and a lower bit comparing portion each having a comparison stage for alternately performing a reset mode of sampling a voltage of an analog signal, and a comparison mode of comparing the voltage of the analog signal with the corresponding one of the plurality of different reference voltages; and a reference voltage selecting portion configured to select the reference voltages corresponding to a comparison result obtained from said higher bit comparing portion from the plurality of different reference voltages generated in said reference voltage generator, and outputting the reference voltages thus selected to said lower bit comparing portion; said serial-parallel type analog-to-digital converter serving to convert the analog signal into a digital signal in accordance with the comparison results obtained from said higher bit comparing portion and said lower bit comparing portion; wherein said lower bit comparing portion includes