INPUT BUFFER

摘要

PURPOSE: An input buffer is provided to improve reliability of device by obtaining setup/hold time margin by reducing skew of output signal, although external circumstance is changed. CONSTITUTION: The constant current source is connected to power supply voltage and generates the constant current. The first transistor flow the current from the constant current source in response to the first output signal. The second transistor mirrors the current from the first transistor in response to the first output signal and generates the second output signal. The plurality of third transistors are connected parallel between the terminal which the first output signal is output to and the ground voltage and responsive to reference voltage. The plurality of forth transistors are connected parallel between the terminal which the second output signal is output to and the ground voltage and responsive to input signal. The switching devices control the connection between the plurality of third transistors and the plurality of forth transistors.