| 摘要 |
PROBLEM TO BE SOLVED: To provide an excess input protecting apparatus capable of surely interrupting the supply of an input signal of an excessive input level to a receiving circuit, and radio equipment. SOLUTION: In the radio equipment 10A, a detection circuit 18, a protection circuit 20 and a receiving circuit 16 are connected in this order at the input side of the receiving circuit 16. A detection diode 40a and a resistor 42a detect a first detection output V1, and a detection diode 40b and a resistor 42b detect a second detection output V2 corresponding to a reflected wave component of an input signal S1. When the respective detection outputs V1 and V2 exceed a threshold voltage VG in a gate terminal G, an FET 48 of the protection circuit 20 establishes an on-state between a drain terminal D and a source terminal S and grounds a transmission line 46. COPYRIGHT: (C)2008,JPO&INPIT
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