PURPOSE: To provide a switch by which transit loss due to parasitic capacitance is prevented from increased and isolation characteristic from being deteriorated and with low transit loss and high isolation by connecting an inductor in parallel with a FET with wide gate width and compensating the parasitic capacitance.
CONSTITUTION: The transit loss due to the parasitic capacitance can be prevented from being increased by the parallel resonance of the parasitic capacitance of the FET3 and the inductor L2, and also, the isolation can be prevented from being deteriorated, and a noise from a transmission circuit side in reception can be blocked. In other words, since the parasitic capacitance when the FET2 is turned off causes the increment of the transit loss on a transmission side, the transit loss in a transmission mode can be prevented from being increased by connecting the inductor L1 in parallel with the FET2. In the reception, since the FET2 is turned on, the source of the FET can be connected to the drain with low impedance, which makes the inductor L1 give no influence on transit characteristic.
OKAMOTO TATSUTO
KITAYAMA TARO
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