| 摘要 |
PURPOSE:To improve the operation speed in a simple constitution in the logical operation circuit, specially, the TTL (transistor transistor logic) circuit. CONSTITUTION:Since clamp diode D1 such as a Schottky diode is connected between the base of transistor Q1 and the collector of transistor Q2, the collector potential at the time when transistor Q2 is turned on is clamped by diode D1. Consequently, the amplitude of the collector potential of transistor Q2 becomes small, and switching characteristic can be improved. That is, the voltage can reach immediately the threshold voltage of transistor Q3 since the amplitude of the collector potential of transistor Q2 become small, so that output signals corresponding to input signals can be led out to output terminal OUT in a high speed. |
