| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switch circuit apparatus whose cost is suppressed by using a DPDT switch not employing a logic circuit for an antenna changeover switch. <P>SOLUTION: A shunt attached DPDT switch circuit apparatus is controlled by three control terminals CTL 1 to CTL 3 without the need for provision of a logic circuit. Since it is not required to provide the logic circuit, the chip size is decreased, the parts count and the manufacturing cost can be reduced and the manufacturing process can be simplified. Further, provision of a shunt FET and a FET 3 can greatly contribute to the improvement of the isolation. Moreover, provision of a means for isolating first and second switching elements in terms of DC, a means for connecting a gate of the second switching element to ground and a means for connecting a drain or a source of the second switching element to ground or the like can solve a problem of deterioration in the switch circuit apparatus due to an electrostatic breakdown voltage. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
