Integrated circuit having an operation voltage supplying depletion type MISFET of high breakdown voltage structure

摘要

A depletion type MISFET is connected between a power voltage supply line of a transistor logic circuit block and a power source voltage terminal. The gate electrode of the depletion type MISFET is connected to a reference voltage. The transistor logic circuit block has a driving MISFET and a load connected in series between the power voltage supply line and the reference voltage. The load of the transistor logic circuit is similarly constituted by a depletion type MISFET, while the driving MISFET is of enhancement type. The driving MISFET and the load MISFET in the transistor logic circuit block are built-in in a monolithic semiconductor integrated circuit, together with the MISFET for the power voltage supply to the transistor logic circuit. The drain of the power voltage supplying MISFET is connected to the power voltage supply terminal, and is made to have a high breakdown voltage structure so that the breakdown voltage between the drain and the substrate of the power voltage supplying MISFET may be larger than that of the load MISFET.