Hitachi, Ltd.

Shinji Kadono

Yukio Suzuki

Masahiro Iwamura

Ikuro Masuda

Akira Uragami

Masayoshi Yoshimura

Toshiaki Matsubara

Tatsumi Yamauchi

Manabu Shibata

Tsuneyo Chiba

Kiyoshi Umezawa

Akira Urragami

Akiro Uragami

In an input level converter for TTL--CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS--TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.

BiCMOS tri-state output driver

Level conversion circuitry for a semiconductor integrated circuit

In an input level converter for TTL-CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS-TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.

In an input level converter for TTL - CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS - TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.

A semiconductor integrated circuit is so designed that it is possible to form any one of the three different kinds of circuit configuration, that is, an inverter circuit, a Schmitt circuit and a common-mode circuit, as desired, by employing circuit elements prepared in advance and by changing wiring. Also disclosed is a semiconductor integrated circuit having these circuit configurations. The output stage of any one of the three kinds of circuit is constituted by a bipolar transistor, and the other portions are constituted by MOS field-effect transistors.

Semiconductor integrated circuit

Semiconductor integrated circuit with a bi-MOS input circuit for

Bicmos gate array

A switching circuit comprises a pre-stage circuit coupled to receive an input signal and an output stage, wherein an output signal having a phase opposite to that of a signal of an input terminal IN can be obtained from an output terminal OUT of the output stage. The pre-stage circuit includes a p-channel MOSFET M1 and an n-channel MOSFET M2 that receive input signals at their gates. The output stage includes two NPN transistors Q1 and Q2 that are connected in series. The drain output of the p-channel MOSFET M1 is applied to the base of one of the transistors of the output stage, and the source output of the n-channel MOSFET M2 is applied to the base of the other of the transistors of the output stage. A third MOSFET M3 is coupled between a power supply and the p-channel MOSFET M1 and the n-channel MOSFET M2. When the MOSFET M3 is rendered non-conductive by a control signal EN, both MOSFETs M1 and M2 and both NPN transistors Q1 and Q2 become non-conductive irrespective of the signal of the input terminal IN. Under this condition, the output terminal OUT is in a floating state. Thus, the switching circuit is a tri-state circuit.

Inverting logic buffer BICMOS switching circuit using an enabling switch

In a refresh control system including a main memory having a volatile memory, at least one processing unit for accessing the main memory, a memory bus for effecting signal transfer between the main memory and the processing unit and a supervision circuit for allotting use of the memory bus in response to a request signal, the refresh control system is characterized by a refresh control circuit for transferring the request signal to the supervision circuit at the time the refresh signal is required and for commanding the initiation of the refresh operation to the main memory in response to a grant signal from the supervision circuit.

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Fussa, Japan

Shinji Kadono