| 摘要 |
PURPOSE:To transmit signals securely without disturbing the operation of an I<2>L circuit by supplying a driving current to an output transistor via a transistor which performs clamping between an injector current supply line and signal input terminal. CONSTITUTION:The voltage between injector current supply line 4 of block 3b provided with NPN transistor TR1A for the initial-stage inputting of I<2>L circuit 3, and signal input terminal 3A is clamped at base-emitter voltage VBE of clamping TR24. Therefore, the potential at terminal 3A of circuit 3 never drops below the emitter potential of TR24 and even when TR23 of input-side connecting circuit 20 turns on, the subtraction of the collector current of TR2 for an injector or more is never done, so that the arithmetic operation of circuit 3 is not disturbed. Further, since the potential at terminal 3A is clamped, malfunction due to the formation of a thyristor will not occur even if the collector of another TR 1B is connected to terminal 3A. |
