Semiconductor memory device

Abstract

The present invention provides a semiconductor memory device whose circuit area is comparatively small and that improves holding characteristics of data in a memory cell. In a word line voltage generator, a voltage Vdd3 of a second power source that is higher than a voltage Vdd of a first power source supplied to the memory cell is applied to a first operational amplifier circuit and a reference voltage generating circuit, and the reference voltage generating circuit generates a voltage that is higher, by a voltage generated through a diode connection of a p-channel transistor, than the voltage proportional to the voltage Vdd as a first reference voltage Vref, and the first operational amplifier circuit outputs a voltage equal to the first reference voltage Vref as a word line drive voltage Vwl. Thus, a leakage current when the memory cell is off can be reduced, without requiring a charge pump circuit or the like.

Description

technical field [0001] The present invention relates to a semiconductor memory device, in particular to a DRAM (Dynamic Random Access Memory) type semiconductor memory device capable of improving data retention characteristics. In addition, the present invention particularly relates to a semiconductor memory device most suitable for mixed mounting with a logic circuit. Background technique [0002] FIG. 14 is a circuit diagram showing the structure of a memory cell of a conventional DRAM (Dynamic Random Access Memory). 100 is a memory cell, WL is a word line, BL is a bit line, 101 is an access transistor, 102 is a capacitor, and VCP is a cell plate power supply. The memory cell 100 is composed of an access transistor 101 and a capacitor 102 . In addition, the drain of the access transistor 101 is connected to one end of the capacitor 102 , the gate is connected to the word line WL, the source is connected to the bit line BL, and the other end of the capacitor 102 is connec...

AI Technical Summary

Problems solved by technology

[0005] However, in the existing voltage generation circuit using the charge pump method, in order to increase the current capacity, the capacitor circuit can be increased or the capacitor conversion cycle can be shortened, but increasing the capacitor will bring about increased circuit area and increased cost. question

In addition, shortening the conversion cycle requires a high-power drive circuit, which increases the circuit area and increases the current consumption.

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