Patent ID: 8130295
Filing Date: 2012-03-06
Classification: H03M,H04N

Abstract:
1. An analog-to-digital converter that converts an analog input signal into a digital signal, comprising: a comparator configured to compare a reference signal with an input signal and the comparator changes an output state when it is determined that the reference signal and the input signal have a predetermined relationship; and a counter configured to count pulses in order to determine a value of the reference signal when the comparator output state changes, wherein the counter includes a plurality of flip flops that can perform serial input/output, an input and an output of the counter are connected to each other, and the counter can operate in accordance with a counter mode and a shift register mode, wherein, in the counter mode, a data output of each of the plurality of flip flops is supplied to a clock input of a flip flop at a next stage, and, if the output of the comparator is at a predetermined level, the counter functions as a counter synchronized with a counter clock signal, and wherein, in the shift register mode, the plurality of flip flops are cascade-connected, and the counter functions as a shift register synchronized with a shift register clock signal.