| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an antenna failure detecting unit, enabling avoidance of incorrect detection, and that can use a reference voltage of relatively low accuracy. <P>SOLUTION: A switch means (29) capable of shortening both ends of a resistor (28) is inserted in a common line. Only when the both-end voltage of the resistor (28) is to be detected, is the switch means (29) turned to "broken" (OFF). Meanwhile, when the both-end voltage of the resistor (28) is not to be detected, the switch means (29) is turned to "connected" (ON). With this, it becomes possible to eliminate the effect of the resistor (28), and eliminate wasteful loss on the common line at non-detection. Furthermore, since the resistor (28) is used only at failure detection, the resistor value can be increased arbitrarily. Thus, a large both-end voltage can be fetched, and the allowed range of the reference voltage for failure detection can be broadened, which enables use of a reference voltage of low accuracy. <P>COPYRIGHT: (C)2007,JPO&INPIT |
