| 摘要 |
<p>PURPOSE:To reduce noises by turning a part of output transistors among plural output transistor to a nonconductive condition at the time of faster access timing. CONSTITUTION:In a normal reading mode, input signals OE/-OE become 'H' and 'L' levels respectively, and when a data signal Din becomes 'H' level, P-channel transistors 5/6 become an ON state, N channel transistors 7/8 become an OFF state, and an output Dout becomes 'H' level. On the other hand, input signals PF/-PR becomes 'H' level and 'L' level respectively in a high-speed reading mode, a point E and a point F become 'H' level and 'L' level respectively inspite of a data signal D1n, the P-channel transistor 6 and the N-channel transistor 8 become the OFF state, and only the P-channel transistor 5 becomes the ON state. Thus, the current driving capacity of the output transistor is decreased, and the generation of noises can be controlled.</p> |
