| 摘要 |
PROBLEM TO BE SOLVED: To provide an operational amplifier circuit, capable of operating at a high speed and suppressing reduction of output drive capability. SOLUTION: A constant-current source circuit 31 is provided with a transistor Q22, with which a resistor R1 is connected between the gate and the source, and a current I21 to flow to the resistor R1 and a drain current I22 of the transistor Q22 are matched by transistors Q21, Q23 and Q24. A transistor Q34 of an output stage has the 10-fold element size of the transistor Q22, a resistor R2, with which resistors R2a and R2b, having the same resistance value as the resistor R1, which are connected in parallel between the source and the gate, is connected; a current I32 which is double the drain current I22 is supplied to the resistor R2; and a gate voltage V34 of the transistor Q34 on the output stage is set by this. |
