| 摘要 |
PURPOSE:To achieve output current increment and temperature compensation of a MOS transistor circuit by an output buffer circuit having the mirror constitution dependent upon emitter follower. CONSTITUTION:Output buffer circuit 22 used for increasing the output current of an operational amplifier consists of output buffer 21 and temperature compensation circuit 22, and the output of the operational amplifier has the output current increased considerably due to emitter follower constitution of output buffer 21. Then, since a MOS transistor used as a load has a negative temperature characteristic and bipolar transistor Q21 used as the emitter follower has a positive temperature characteristic, temperature compensation circuit 22 is constituted by the same constitution as the output buffer, thereby forming a mirror circuit. Then, the output of compensation circuit 22 is used as the gate bias of MOS transistor Tr21. Consequently, circuits 21 and 22 are changed similarly for output (Out) to hold the output DC voltage constant due to the gate bias. |
