| 摘要 |
<p>PURPOSE:To set the error value at zero and to obtain a plus-minus symmetrical triangular wave output with a triangular wave generating circuit consisting of a rectangular wave generating circuit and an integration circuit by detecting the output error value of the integration circuit via an integrator and returning the detected error value to the input side of the integration circuit with coincidence secured between the direction and the volume so as to secure negative feedback. CONSTITUTION:An integrator 10 consists of an operational amplifier 8, a resistance R6 and a capacitor 9 and an inverse amplifier 12 consisting of the resistances R7, R8 and an operational amplifier 11 is connected to the output side of the integrator 10. The error value epsilonof the output of an integration circuit 7 is detected as the output voltage (a) of the integrator 10. Then the value epsilon is sent back to the input side of an operational amplifier 5 with coincidence secured between the direction and the volume of the value epsilon so that the detection value of the integrator 10 is negatively fed back via the amplifier 12. Thus a closed loop is formed so that the value epsilon is always equal to zero in terms of a short time. Then a plus- minus symmetrical triangular wave is obtained. Furthermore the time constants of the R6 and the capacitor 9 are extremely increased compared with those of a resistance R5 and a capacitor 6. Thus it is possible to eliminate the variance of a slow time constant, i.e., the offset, the drift, etc.</p> |
