| 摘要 |
PURPOSE:To eliminate a feedback circuit to switch the base current of a transistor at the final stage in a decoder circuit and to simplify a circuit constitution and to aim at the high integration of a circuit. CONSTITUTION:Since the potential of a word line WL1 is low in a read out time, a diode D5 becomes an off state and a current from a VCC through a resistor R1 and the current from the VCC through a resistor R2 are supplied, passing through from the bases to the emitters of transistors Q1 and Q2, to the base of a transistor Q3, making the transistor Q3 on and pulling in a read current from the WL1. Since the potential of the word line WL1 becomes high in a write time, the diode D5 is made as an on state and though the current supply to the base of the transistor Q2 is performed in the same manner as in the read time, a part of the write current flows to the collector of the transistor Q2 through the diode D5, and flows to the base of the transistor Q3 with the base current of the transistor Q2, therefore, a lot of current can be pulled in by the transistor Q3. |
