| 摘要 |
PURPOSE:To attain coarse adjustment control with accurate and stable state by accelerating a spindle motor when a reproducing signal includes a signal where the consecutive range of one signal is within 3 bits and decelerating the spindle motor when the reproducing signal includes a signal where the consecutive range of the signal is 12 bits or over. CONSTITUTION:A counter 7 of 5bit constitution is cleared by the output signal of a trailing detection circuit 2, counts sequentially a reference clock signal D' applied from an AND gate 6 and when the count value reaches n=3, an output is generated from an output port P1 and an output is generated from an output port P2 at n=12. The 3rd flip-flop circuit 8 is reset by an output signal generated from the output port P2 of the counter 7 and reset by an output signal of a trailing detection circuit 2. The output signal of an adder 9 is smoothed by a low pass filter 10 and outputted as a coarse adjusting signal. |
