| 摘要 |
PURPOSE:To form a demodulation circuit of pulse count type not affected by power voltage fluctuation or temperature fluctuation by using two monostable multivibrators formed on one and same chip. CONSTITUTION:Since the pulse width of a pulse outputted from a monostable multivibrator 10 is decided by a time constant setting circuit mounted externally, the width is set equal to that of a monostable multivibrator 5. Moreover, as the multivibrator 10, the same component on the same chip as the monostable multivibrator 5 is used. The cut-off frequency of a low pass filter 11 is selected equal to or less than the cut-off frequency of the low pass filter 6. Thus, even when the circuit constant of the monostable multivibrator is changed due to power voltage or temperature fluctuation, the change is the same to both the monostable multivibrators 5, 10 because they are formed on the same chip. Thus, the optimum comparison set initially is kept at all times. |
