Patent ID: 7400177
Filing Date: 2008-07-15
Classification: H03K

Abstract:
1. A circuit for receiving data, the circuit comprising: an amplifier circuit, which compares a voltage level of an external input signal with a voltage level of an external reference signal, amplifies and outputs a voltage difference between the two compared signals, responds to a control voltage, and maintains constant a swing range of output data; a first latch circuit, which stores and amplifies the output data from the amplifier circuit; and a second latch circuit, which stores or outwardly outputs the output data from the first latch circuit, wherein the amplifier circuit comprises: a first bias unit, which responds to an internal reference signal with a predetermined voltage level and maintains constant the amount of a first current; a second bias unit, which receives the external reference signal, responds to the control voltage, and controls the amount of a second current to be the same as the amount of the first current; a comparison unit, which compares a voltage level of a first node with a voltage level of a second node, and controls a voltage level of the control voltage according to the comparison result; and an amplifier unit, which compares the voltage level of the external input signal with the voltage level of the external reference signal, amplifies and outputs the voltage difference between the two compared signals, responds to the control voltage, and maintains constant the swing range of the output data although the levels of the external reference signal and the external input signal are varied, wherein the amplifier circuit is turned on or off in response to a predetermined amplifier circuit driving pulse.