Transmission amplifying device having transmission power control function

Abstract

Abstract PURPOSE:To eliminate the wastiful power consumption in a control circuit when no transmission signal is supplied to a transmission amplifier, by detecting the power supply current supplied to the transmission amplifier from a power supply circuit when the amplifier is set in an active state and turning on a switch means set between the power supply circuit and the control circuit. CONSTITUTION:When no transmission signal is supplied to an input terminal 11, a transistor TR13 is kept under an OFF state and no power supply current flows to a resistor 26. Thus, no voltage drop is produced at both ends of the resistor 26 with a TR27 kept under an OFF state. Thus, no active voltage is supplied to a control circuit 24 and therefore the circuit 24 is never actuated. When a transmission signal is supplied to the terminal 11, the TR13 is turned on in the negative half cycle of said transmission signal. Then the TR13 performs an amplifying action. When the TR13 is turned on, the power supply current flows to the resistor 26 and a choke coil 15 and the voltage drops are produced at both ends of the resistor 26. Thus, the TR27 is turned on and the active voltage is supplied to the circuit 24 from a regulator 17 and the circuit 24 is actuated.

Inventors

• 👤 Norio Orimo
• 👤 下茂　紀雄

Bibliographic Details