| 摘要 |
PURPOSE:To prevent through current without using a clocked inverter and to share a data bus line by plural preamplifiers. CONSTITUTION:In an initial state, a signal DBE is low potential, transistors 7 to 10 are in a conductive state, bus lines 3, 4 are in precharge potentiai and transistors 11, 12 are kept in a non-conductive state. At the time of' an operation, the signal DBE becomes high potential and the bus lines 3, 4 become a floating state. In this state, one of transistors 5a, 6a become conductive according to the output of a preamplifier 1a, one of the potential of the bus lines 3, 4 rises or falls and one of the transistors 12, 11 become conductive. Thus, the potential of an input line 14 of the main body of a main amplifier 2 becomes low potential or high potential and the output of the preamplifer 1a becomes the input of the main amplifier 2. |
