| 摘要 |
PROBLEM TO BE SOLVED: To reduce the scale of an automatic gain control circuit to the gain control parts of both preceding and next stages. SOLUTION: An automatic gain control circuit 9 includes a comparison part 10 which controls a gain control part 3A of the preceding stage of a variable gain amplifier, a variable attenuator, etc., and a gain control part 4 of the next stage of the variable gain amplifier, etc., and compares the output signal of the part 4 or a detection part 5 with its reference value, a 1st gain control signal output part 11 which outputs the gain control signal of the part 4 based on the comparison output signal of the part 10, and a 2nd gain control signal output part 12 which has a larger time constant than the part 11 and outputs the gain control signal of the part 3A based on the comparison output signal of the part 10. |
