Current mirror type sense amplifier circuits for semiconductor memory devices and methods of operating same

摘要

A sense amplifier circuit includes a first voltage-controlled current source to supply current proportional to a first bias voltage to a reference node and a second voltage-controlled current source to supply current proportional to a second bias voltage to a sensing node. The first and second bias voltages are internally generated in response to an externally applied sense amp control signal. A current mirror circuit is also provided for the sense amplifier circuit. The current mirror circuit commonly deliver current proportional to the voltage level of the reference node to the reference and sensing nodes. A differential amplifier amplifies a difference voltage between reference and sensing nodes. This current mirror type sense amplifier circuit allows data sensing operation to be performed without being influenced from the external conditions and without sensing speed loss due to the instability of the precharge current since the voltage-controlled current sources are controlled by the internal bias voltages.