| 摘要 |
PURPOSE:To eliminate the influence dependent upon noise, by connecting a capacitor between the base and the emitter of a transistor which constitutes the emitter follower circuit of a reference voltage circuit. CONSTITUTION:Capacitor C1 is connected between the base and the emitter of transistor Q9 of reference voltage circuit 3. Therefore, even if noise is generated on the earth line, the noise current is flowed through this capacitor C1 and capacitor C2 provided at external terminal P6, and DC bias voltage VB is not changed. That is, since the positive half wave of the noise is detected by emitter follower transistor Q9 not to charge external capacitor C2, DC bias voltage VB does not rise to the positive direction, so that lowering of the input level margin and malfunctions can be prevented. |
