Abstract: An AFC-control D/A converter which controls a reference frequency oscillator is a voltage-potentiometer-type D/A converter containing three voltage followers. At least in the latter-stage voltage follower, an NMOS differential input circuit, a CMOS output circuit, and a bias circuit are supplied with an external power voltage. However, PMOS differential input circuit is supplied with an internal regulated power supply voltage generated by a reference voltage generator. Even if there is a shift in the pair nature of MP1 and MP2 of the differential PMOS, an increase of current of MP3 of a PMOS current source due to the increase of the external power voltage is suppressed. Also an input offset voltage of the differential PMOS does not increase, and a change of an AFC control analog output signal can be reduced.

Abstract: In accordance with one aspect of the invention, a semiconductor integrated circuit is provided wherein an input circuit is formed by a phase split circuit having a bipolar transistor which outputs an inverted output from the collector and a non-inverted output from the emitter. The emitter follower output circuit is driven by an inverted output of the phase split circuit. Meanwhile, an emitter load of the emitter follower output circuit is formed by a transistor, and the emitter load transistor is temporarily driven conductively by a charging current of the capacitance to be charged by the rising edge of the non-inverted output of the phase split circuit. As a second aspect of the invention, a logic circuit is formed of a logic portion and an output portion. The output portion includes an emitter follower output transistor receiving an output signal generated by the logic portion and an active pull-down transistor receiving at its base a signal supplied thereto through a capacitance element.

Abstract: In accordance with one aspect of the invention, a semiconductor integrated circuit is provided wherein an input circuit is formed by a phase split circuit having a bipolar transistor which outputs an inverted output from the collector and a non-inverted output from the emitter. The emitter follower output circuit is driven by an inverted output of the phase split circuit. Meanwhile, an emitter load of the emitter follower output circuit is formed by a transistor, and the emitter load transistor is temporarily driven conductively by a charging current of the capacitance to be charged by the rising edge of the non-inverted output of the phase split circuit. As a second aspect of the invention, a logic circuit is formed of a logic portion and an output portion. The output portion includes an emitter follower output transistor receiving an output signal generated by the logic portion and an active pull-down transistor receiving at its base a signal supplied thereto through a capacitance element.

Abstract: A unitary semiconductor integrated circuit is constructed using a non-threshold logic NTL circuit for a circuit which has a light load or a light load driving capability, using an NTL circuit additionally provided with an emitter-follower output circuit for effecting a circuit having a comparatively heavy load, and using a super pull-down logic (SPL) circuit for effecting a circuit having a heavy load. The NTL circuit thereof which receives an output signal generated by the emitter-follower output circuit or from the SPL circuit associated with a preceding logic gate circuit stage uses, as its operating voltage, the operating voltage of the emitter-follower output circuit or that of the SPL circuit.

Abstract: A semiconductor integrated circuit wherein an input circuit is formed by a phase split circuit consisting of a bipolar transistor which outputs an inverted output from the collector and non-inverted output from the emitter, the emitter follower output circuit is driven by an inverted output of the phase split circuit, meanwhile, an emitter load of the emitter follower output circuit is formed by a transistor, and the emitter load transistor is temporarily driven conductively by a charging current of the capacitance to be charged by the rising edge of the non-inverted output of the phase split circuit.