| 摘要 |
PURPOSE:To obtain a circuit possible for operation immediately after application of power by providing a circuit setting the level of a latch circuit to a desired logical output level without initializing after application of power in the latch circuit of a current switching type logical circuit. CONSTITUTION:A potential at a point X is high just after application of power, a transistor(TR)QX is turned on and a current flows to a resistor R3 independently of the state of a TRQ9. Then a base potential of a TRQ7 rises, the TRQ7 is turned on and a TRQ8 is turned off. That is, a current flows to any of TRQY, Q4 and Q5 in the current switching circuit and the current flows in a path in order of maximum potential, R1, QY, Q7, constant current source and minimum potential. The base potential of the TRQ1 is decreased by the voltage drop of the resistor R1, the TRQ1 is turned off, no current flows to resistors R5, R2, then the base potential of the TRQ2 is high, the TRQ2 is turned on and a current flows to the resistor R4. Thus an output Q goes to a high level and an output Q' goes to a low level. |
