摘要 |
A one-transistor type DRAM is provided to increase efficiency of a sense amplifier by generating a plurality of reference voltages reflecting multi-bit data write/retention characteristics of a main cell by using a reference cell array. According to a one-transistor type DRAM using a floating body storing device controlled by a word line as being connected between a bit line and a source line, a plurality of source lines and word lines are arranged in a row direction. A plurality of bit lines are arranged in a column direction. A plurality of reference bit lines are arranged in a column direction. A cell array(30) includes the floating body storing device, and is formed on a region where the source line, the word line and the bit line intersect with each other. A reference cell array(20) includes the floating body storing device, and is formed on a region where the source line, the bit line and the reference bit line intersect with each other, and outputs a plurality of different reference currents. A reference voltage generation part(40-60) is connected to the reference bit line, and generates a plurality of different reference voltages corresponding to the reference currents. A sense amplifier(S/A) and a write driving part(W/D) are connected to the bit line, and are applied with the reference voltages.
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