| 摘要 |
PURPOSE:To make easy the circuit integration and to make low voltage operation possible, by using one multivibrator as stable type at modulation and using it as stable type at demodulation, making the charge/discharge capacitor as unbalanced type and using one pin for the capacitor. CONSTITUTION:The capacitor C1 is charged at the on period of a switching transistor (TR)Q2, and the charge is discharged at the conduction period of TRQ6 connected in parallel with the capacitor C1. Further, the monostable multivibrator is constituted with TRs Q1, Q2, capacitor C1, voltage comparison circuits CO1, CO2, and RS-FF10, and modulation input is fed to input terminal t1 and the demodulation input is fed to the input terminal t4. At the modulating operation, the voltage Vcc by the signal S0 is fed to the input terminal t5 to turn off TRs Q6-Q8. The multivibrator is operated as astable type at modulation with the charging voltage of the capacitor C1. Further, at demodulation, the signal S0 is made to 0 level, TRs Q6-Q8 are off, the multivibrator is operated as stable type, low voltage operation is made possible, and circuit integration is made. |
