To easily match characteristic impedance to 50 Ω even if a board is 5.4 mm × 4.0 mm or smaller in size.
A switch circuit for switching a transmission circuit and a reception circuit comprises an antenna terminal; a transmitting terminal; a receiving terminal; a first one-end grounded transmission line connected between the antenna terminal and the transmitting terminal; a first diode connected between the first transmission line and the antenna terminal; a second transmission line connected between the antenna terminal and the receiving terminal; a first one-end grounded capacitor and a second diode connected in series between the second transmission line and the receiving terminal; and a voltage-controled terminal connected between the second diode and the first capacitor for controlling the diode. The switch circuit is characterized by comprising a high-frequency switch circuit for switching the transmission and reception circuits connected to the second one-end grounded capacitor between the second transmission line and the receiving terminal, and a multiband high-frequency switch module comprising these on a laminate board.
FUKAMACHI KEISUKE
TADAI HIROYUKI
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