| 摘要 |
PURPOSE:To prevent the quality degradation of a regenerative signal and to improve reliability by making the time constant of a driving current control means enough longer than the response time of an AGC circuit. CONSTITUTION:The integration circuit 9 of a time constant K, which is enough longer than the response time of the AGC of a regenerative signal processing circuit, is provided between a D/A converter 7 and a V/I converter 8. One terminal of this integration circuit is connected to the output part of the D/A converter 7, a switching terminal B of a switching circuit 10 is connected to the output part of the D/A converter, a switching terminal C is connected to the other terminal of the integration circuit 9 and a terminal A is connected to the input part of the V/I converter 8 respectively. Accordingly, when the switching circuit 10 is operated or the capacity value or resistance value of the integration circuit 9 is changed and the time constant is made longer than the response time of the AGC, the response of the AGC of the regenerative signal processing circuit can be followed up. Thus, the quality degradation of the regenerative signal can be prevented. |
