| 摘要 |
PURPOSE:To obtain an oscillating output possible for the adjustment of an amplitude of a sinusoidal wave output, by constituting a positive feedback loop with a band-pass filter, a comparator and an amplitude adjusting circuit. CONSTITUTION:The comparator 1 converts a sinusoidal wave signal into a rectangular wave signal. The amplitude adjusting circuit 2 adjusts the amplitude of the rectangular wave signal with a control voltage Vin. The band-pass filter 3 consists of the 2nd order band-pass filter of multiplex feedback type, for example, and the output is fed back positively to the comparator 1. When a power supply is applied to the circuit, a signal appears at an output OUT and is inputted to the comparator 1 to be a rectangular wave output. This rectangular wave output is limited so as to be the same amplitude as that of the control voltage Vin and inputted to the band-pass filter 3. The amplitude of the sinusoidal wave output is controlled linearly with the control voltage Vin. |
