Patent ID: 8546980
Filing Date: 2013-10-01
Classification: H04B

Abstract:
1. A radio-frequency module comprising: a first semiconductor chip; a second semiconductor chip; and a wiring board where the first and second semiconductor chips are mounted, the first semiconductor chip comprising: a first power amplifier circuit which amplifies an input signal of a first frequency band and outputs a transmission signal of the first frequency band; a voltage selection circuit which selects and outputs a first voltage level or a second voltage level; and a control circuit which, in response to a mode setting signal indicative of the first frequency band or a second frequency band, controls the first power amplifier circuit and the voltage selection circuit and outputs a first control signal and a second control signal using output of the voltage selection circuit, the second semiconductor chip comprising: a first transmission terminal to which the transmission signal of the first frequency band from the first power amplifier circuit is inputted; a second transmission terminal to which a transmission signal of the second frequency band is inputted; an antenna coupling terminal; a first switch which is provided between the first transmission terminal and the antenna coupling terminal and on/off-controlled by a voltage level of the first control signal; and a second switch which is provided between the second transmission terminal and the antenna coupling terminal and on/off-controlled by a voltage level of the second control signal, wherein the voltage selection circuit comprises an oscillation circuit and generates the second voltage level by boosting the first voltage level using a clock signal from the oscillation circuit, wherein when the second frequency band is selected by the mode setting signal, the control circuit causes the voltage selection circuit to select the second voltage level, and respectively turns off the first switch and turns on the second switch by outputting the first and second control signals having an amplitude between a ground voltage level and the second voltage level, wherein when the first frequency band is selected by the mode setting signal, the control circuit stops the oscillation circuit of the voltage selection circuit and causes the voltage selection circuit to select the first voltage level, and respectively turns on the first switch and turns off the second switch by outputting the first and second control signals having an amplitude between the ground voltage level and the first voltage level.