| 摘要 |
PURPOSE:To facilitate the control of the oscillation frequency for the free-running multivibrator by connecting the resistance in series to the feedback capacitor. CONSTITUTION:When transistor TrQ1 is on with TrQ2 turned off each, the emitter voltage of TeQ1 is identical virtually to power voltage VCC. And the base voltage features the potential of VCC-VBE(Q1). When the emitter potential of TrQ2 lowers with i/CX down to VD-VBE(Q2), transistor Q2 is turned on. And when the collector potential lowers down to VD from VCC, transistor Q1 is turned off. In this instant, the emitter potential of TrQ1 rises just by VD-2RXi1. In other words, the feedback quantity can be controlled by resistance RX and thus the frequency increase/decrease ratio caused by control voltage VZ can be increased. |
