| 摘要 |
PROBLEM TO BE SOLVED: To protect two or more internal circuits (ICs) which process signal ranging from high frequency band to low frequency band, from electrostatic discharge by positive and negative static electricity. SOLUTION: A protective circuit of two or more multi-stage connection transistors in diode connection with small parasitic capacitance and no possibility of malfunction, even if input signal more than power supply voltage is applied, is assembled in the internal circuit operated at high frequency band, while a protective circuit made up of a transistor in one diode connection is assembled in the internal circuit operated at low frequency band. Then, the protective circuit has two system protective circuit structure, in which directions of current flows of protective current are reversed mutually even for positive and negative static electricity. COPYRIGHT: (C)2008,JPO&INPIT
|
