Patent ID: 9054784
Filing Date: 2015-06-09
Classification: H03G,H04B

Abstract:
1. A signal switching apparatus, comprising: a switch circuit configured to have a common terminal and first to third terminals, and to enable two terminals among the first to third terminals to be simultaneously connected to the common terminal while enabling the first to third terminals to be individually attachable and detachable to and from the common terminal; and an amplification circuit having an input terminal connected to the first terminal, and an output terminal connected to the second terminal, wherein gain in the output terminal of the amplification circuit being an output point, with respect to a signal level in the common terminal being an input point, is switched to a first gain when only the first terminal is connected to the common terminal, a second gain when only the second terminal is connected to the common terminal, and a third gain when the first terminal and the second terminal are simultaneously connected to the common terminal, and wherein, when a signal level of an input signal input to the common terminal is smaller than a threshold value, only the first terminal is connected to the common terminal, when the signal level of the input terminal exceeds a second threshold value larger than the first threshold value, only the second terminal is connected to the common terminal, and when the signal level of the input signal is a value between the first threshold value and the second threshold value, the first terminal and the second terminal are simultaneously connected to the common terminal.