Patent ID: 8368484

Claim:
A high-frequency switch module comprising: a switch IC including a single common port connected to an antenna and a plurality of separate ports individually connected to a plurality of transmission/reception circuits, the switch IC being arranged to switch between the plurality of separate ports to be connected to the single common port; an ESD device connected between a ground and a transmission line arranged to connect the single common port of the switch IC and the antenna; and a multilayer substrate including an upper surface on which the switch IC and the ESD device are mounted and a lower surface on which a first external-connection ground electrode arranged to connect the ESD device to ground and a second external-connection ground electrode arranged to connect the switch IC and the plurality of transmission/reception circuits to ground are provided; and a first ground connection path arranged to connect the ESD device to the first external-connection ground electrode and a second ground connection path arranged to connect the switch IC and a circuit element included in the plurality of transmission/reception circuits to the second external-connection ground electrode are separately provided in the multilayer substrate.