| 摘要 |
<p>PURPOSE:To simplify the circuit constitution and to reduce the cost, by controlling the depth of modulation independently of the center frequency. CONSTITUTION:When an output of a flip-flop 6 is denoted as 1, a switch 3 is connected to the position (a), and a capacitor C is charged with a current source 1. Inversely, the output of the circuit 6 is denoted as 0, the switch 3 is connected to the position (b) and the charge in the capacitor C is discharged to a current source 2. When a potential VOSC of the capacitor C is higher than a reference voltage Vu of a comparator 5, the output of the comparator goes to 1 to reset the circuit 6 and the output goes to 0. Inversely, when the potential VOSC is lower than a reference potential Vl of a comparator 4, the output of the circuit 6 goes to 1. Thus, the oscillating frequency (output of the circuit 6) can be controlled with currents i1 and i2. Further, the depth of modulation can be controlled with the voltages Vu and Vl.</p> |
