The LC78621E is a CMOS LSI that implements the signal processing and servo control required by compact disk players, laser disks, CD-V, CD-I and related products. The LC78621E provides several types of signal processing, including demodulation of the optical pickup EFM signal, de-interleaving, error detection and correction, and digital filters that can help reduce the cost of CD player units. It also processes a rich set of servo system commands sent from the control microprocessor. It also incorporates an EFM-PLL circuit and a one-bit D/A converter.