| 摘要 |
<p>PURPOSE:To provide a mask ROM operating at high speed by reducing load capacity generated at bit lines. CONSTITUTION:The value of a data line D1 to which bit lines B1-B4 are connected via N channel MOS transistors S1-S4 is inputted to an either input terminal A of a 2-1 selector SEL via a sense amplifier. The output of the sense amplifier SA1 is inverted by an inverter INV1 and inputted to the other input terminal B of the 2-1 selector SEL. The value of a data line D2 to which N channel MOS transistors T1, T2 are connected is inputted to a signal selecting terminal S of the 2-1 selector SEL via a sense amplifier SA2. When a high level signal is inputted to the signal selecting terminal S of the 2-1 selector SEL, the input terminal B is selected, and when a low level signal is inputted, the other input terminal A is selected.</p> |
