The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 22, 1997
Filed:
Aug. 24, 1995
Takaaki Yamada, Kanagawa, JP;
Yasushi Nakamoto, Kanagawa, JP;
Sony Corporation, , JP;
Abstract
A communication circuit system of an IC card etc. including a voltage drop circuit having a complementary type transistor circuit comprising a p-channel and an n-channel transistor connected together, the circuit being connected to a power source voltage and generating a voltage corresponding to the sum of the threshold voltages of the p-channel transistor and n-channel transistor and supplying the same to a load circuit; an oscillation circuit having a complementary MOS inverter, a capacitor connected to the input side of the complementary MOS inverter, and resistance elements connected between the input and output of the complementary MOS inverter; and a wave detection circuit having a first and second MOS transistors with drains and gates connected to each other and a current source, nodes between the drains and the gates of the first and second MOS transistors being connected to the current source, the gate of the first MOS transistor being connected to a signal input line, and the current capacity of the second MOS transistor being set larger than the current capacity of the first MOS transistor.