Automatic gain control circuit

Abstract

Abstract PURPOSE:To constitute a circuit suitable for circuit integration without using a capacitor, by controlling the gain of a variable gain control amplifier with switching by means of a counter. CONSTITUTION:An input signal v1 is amplified at a variable gain amplifier 15, and an output v2 is compared with a reference voltage v3. Further, when v2>v3 (reference signal level of a reference voltage source 16), an FF18 is set and a clock signal v7 is input to a counter 21. On the other hand, an output 24 of an ROM22 controls on/off of switches 9-14, to control the gain of an amplifier 15. Further, a counter 20 reduces the content of the counter 21 when the signal v1 decreases, and the gain of the amplifier 15 is increased. Accordingly, since no capacitor is used to keep the peak hold characteristics, the circuit suitable for circuit integration can be constituted.

Inventors

• 👤 Toru Koyama
• 👤 Masaru Yamaguchi
• 👤 Fumio Akashi

Bibliographic Details