| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact gain control circuit and an ultrasonic image device.SOLUTION: The gain control circuit includes: a voltage generation section for generating a first voltage varying linearly with time; a voltage squaring section for outputting a second voltage that is the square of the first voltage generated by the voltage generation section; a resistance section having a resistance characteristic where a resistance value varies quadratically with time in accordance with the second voltage output from the voltage squaring section; and an amplification section with a gain varying quadratically with time in accordance with the resistance value of the resistance section. |
