Patent ID: 6473343
Filing Date: 2002-10-29
Classification: G11C

Abstract:
A signal amplification circuit for amplifying and sensing a difference between an input current and a reference current which flow a first and a second input nodes, respectively, comprising:a reference voltage generation part for generating a reference voltage at a first node in accordance with said reference current; a first transistor of a first conductive type being electrically connected between a first power supply node that supplies a first voltage and said first input node so as to allow said input current to pass through; a current comparison part for generating a voltage at a second node in accordance with a difference between said input current and said reference current based on said reference voltage, said current comparison part including a second transistor of said first conductive type being electrically connected between said first power supply node and said second node and forming a current mirror with said first transistor and a third transistor of a second conductive type which is the opposite conductive type of said first conductive type, said third transistor having a control electrode which receives an input of said reference voltage and being electrically connected between a second power supply node that supplies a second voltage and said second node; and an output level setting part for outputting a voltage corresponding to a sensing result to an output node, in accordance with a voltage of said second node, said output level setting part includes a fourth transistor of said first conductive type being electrically connected between said first power supply node and said output node and having a control electrode which receives a voltage in accordance with said reference voltage, and a fifth transistor of said second conductive type being electrically connected between said output node and said second power supply node and having a control electrode connected to said second node; wherein currents which flow through said fourth and fifth transistors, respectively, are in balance in the condition where said input current and said reference current are equal.