Overview

The LC7874E is a CMOS LSI that provides the signal processing needed for compact disc graphics (CD-G) on a single chip. The LC7874E accepts subcode R to W signals output from a CD player DSP LC786X Series, LC7862XE Series, or LC7863XE Series device, and performs de-interleaving, error detection and correction, graphic instruction processing, and image processing.

Features

• A CD-G decoder can be configured using a three-chip combination of this LSI—the LC7874E—with external RAM (64K × 4 bits) and an LC78010E digital RGB encoder.

• Performs insertion and protection of CD subcode R to W sync signals and detection of R to W signal deinterleave error signals.

• Has two crystal oscillators, for NTSC and PAL, with simple switchover by means of a control pin. Connecting a crystal resonator of 14.31818 MHz for NTSC and 17.734476 MHz for PAL enables the standard clock and other necessary timings to be generated internally.

• Performs CD graphics instruction processing and drawing functions, and controls image display.

• Has microcomputer interface functions, allowing set upgrading.

• Provides superimposition support.

• Has a color bar signal output function.

• DRAM interface and RGB output and sync signal output are 3-state outputs.