| 摘要 |
PURPOSE: To obtain an automatic gain control circuit in which power consumption in a radio receiver is suppressed low by improving inter-modulation characteristic of an amplifier circuit used for a radio receiver such as a pager. CONSTITUTION: A signal intensity detection section 29 provides an output of a detection signal to a CPU 30 in response to a signal level detected by a current signal received from an IF amplifier 27. The CPU 30 provides an output of a switching signal controlling a changeover section 31 to a changeover section 31 based on the detection signal received from the signal intensity detection section 29. The changeover section 31 throws a contact 31a or a contact 31b to a moving contact 31c based on a switching signal received from the CPU 30 and a DC power supply Vcc supplies power to an RF amplifier 22 or an attenuator section 32. |
