LC7868E Datasheet | SANYO

CMOS LSI LC7868E, 7869E Digital Signal Processor for pact Disc Players Overview The LC7868E and the LC7869E are CMOS LSIs for signal processing and servo control in pact disk players, laser disk players, and CD-V and CD-I products. Only the digital filtering blocks differ between the LC7868E and the LC7869E. These products perform signal processing such as demodulation of the EFM signal from the optical pickup, de-interleaving, error detection and correction, and digital filtering that can contribute to end product cost reduction. Furthermore, these products also process mands from the system microprocessor directed at the servo system. These products also support direct interface with the Sanyo LC78815 and LC78816 serial input D/A converters. Functions - HF signals that are input are sliced at an accurate level, converted to EFM signals, and undergo phaseparison with VCO for PLL playback at an average of 4.3218 MHz. ° Through external connection of a 16.9344 MHz crystal oscillator, all required timing signals can be generated on-chip, including the standard clock. Frame phase difference signals made from the playback clock and the reference clock can control the speed of the disc motor. Performs detection, protection, and interleaving of frame synchronization signals, ensuring stable data reading. Demodulates EFM signals and performs conversion to 8-bit symbol data. Separates subcodes from EFM demodulation signals for output to an external microprocessor. After CRC checking, Q subcode signals are output to the microprocessor by the serial I/O interface (LSB-first output selectable). On-chip RAM performs buffering for EFM demodulation signals, as well as absorbing up to +4 frames of jitter due to fluctuations in the speed of disc rotation. Performs unscrambling and deinterleaving for rearranging the EFM demodulation signals into the specified sequence, ¢ Performs detection and correction of error signals, as wall es erar fina crocessing (double Cl and...