PURPOSE: To finely control the zero point and pore frequencies of a PLL loop filter by not using a passive element constant but using an electronic circuit.
CONSTITUTION: A timing error detector 41 detects the extent of timing error between a timing clock 34 outputted from a controlled oscillator 44 and an input signal 33 and converts this detected extent of timing error in accordance with two set conversion coefficients different by values to output two converted extents of timing error. A loop filter 43 is provided with the transfer function, where the zero point frequency in the loop filter 43 is changed by two conversion coefficients, and the transfer function where a control signal is amplified in accordance with an indicated gain and the pole frequency in the loop filter 43 is changed by the indicated gain. A setting means sets and changes two conversion coefficients and the gain to control the zero point frequency and the pole frequency.
| JPH03192576 | INFORMATION RECORDING AND REPRODUCING DEVICE |
HASE KENICHI
KIMURA HIROSHI
NARA TAKASHI
Next Patent: PHASE SYNCHRONIZING CIRCUIT AND DATA REPRODUCING DEVICE