Patent ID: 8559226

Claim:
A method for a reading operation on a memory cell of nonvolatile semiconductor, comprising: performing a first sense operation during a first period, the first sense operation including: applying a first potential to a gate of a first transistor in order to discharge a potential of a SEN node, the first transistor being electrically connected to the SEN node; applying a second potential to a gate of a second transistor in order to stop discharging the potential of the SEN node after applying the first potential, the second transistor being electrically connected to the SEN node; and applying a third potential to a gate of a third transistor in order to fetch data of the SEN node into a latch circuit in a sense amplifier; recharging the SEN node during a second period after the first period, the recharging the SEN node including: applying a fourth potential to a gate of a fourth transistor in order to recharge the SEN node; and performing a second sense operation during a third period, the second sense operation including: applying a fifth potential to the gate of the first transistor in order to discharge the potential of the SEN node; applying a sixth potential to the gate of the second transistor in order to stop discharging the potential of the SEN node after applying the fifth potential; and applying a seventh potential to the gate of the third transistor in order to fetch a data of the SEN node into the latch circuit.