| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a current sensing circuit for a semiconductor memory device, by which a weak current can be sensed at high speed. <P>SOLUTION: The current sensing circuit which detects a difference between a cell current Icel and a reference current Iref, includes: current mirror circuits 41, 22 of which the input terminal is connected with a reference current source 30; a differential amplifier 100 to the input terminal 100a of which potential SAOUT of an electrical connection point between the output terminal of the current mirror circuit and a memory cell MC is supplied, and to the input terminal 100b of which reference potential VREF2 is supplied; and an equalizing circuit 24 for short-circuiting the input terminals 100a, 100b of the differential amplifier 100 in response to an equalizing signal EQ. Since the input terminals 100a, 100b can be kept at the same potential immediately before the start of sensing operation, a highly sensitive sensing operation can be performed at high speed even when the cell current Icel is weak. <P>COPYRIGHT: (C)2010,JPO&INPIT |
