| 摘要 |
PROBLEM TO BE SOLVED: To provide an operational amplifier that protects a transistor of an output buffer circuit and prevents an input offset voltage variation due to a leakage current with the addition of a small number of elements.SOLUTION: The operational amplifier having a Gm amplifier 11 for voltage/current-converting an input voltage, a current mirror circuit 12 having lateral PNP transistors Q1, Q2 connected as an active load on the Gm amplifier 11, and an output buffer circuit 13 having an NPN transistor Q3 fed with an output of the current mirror circuit 12 and a current source I1 includes a transistor Q4 having a collector and a base connected to a base of the transistor Q3 and an emitter connected to an emitter of the transistor Q3. |
