| 摘要 |
PURPOSE:To reduce remarkably number of components of an oscillating circuit using a lead filter, by combining a PNP and an NPN transistor (TR) so as to use a resistor for a feedback resistor and a bias resistor for an inverting amplifier in common. CONSTITUTION:The phase inverting amplifier RA is formed with the NPN TR23 and an emitter follower EF is formed with the PNP TR24. Further, the lead filter LF is connected between an output terminal of the amplifier RA and an input terminal of the emitter follower circuit EF. Moreover, a feedback circuit PF is connected between an output terminal of the emitter follower circuit EF and an input terminal of the amplifier RA, and the feedback resistor 28 is used in common for the bias resistor of the TR23. Thus, the number of components of the oscillating circuit using the lead filter is reduced remarkably. |
