LC78684E-US-E

Overview

The LC78684E integrates, on a single chip, CD-ROM signal-processing functions, MP3 signal-processing functions, and CD-DA shockproof signal-processing functions. The LC78684E achieves significant power savings by implementing signal-processing functions using hardwired structures.
A CD player that supports playback of MPEG audio (MP3) recorded on CD media as well as CD-DA shockproof playback can be implemented by combining this IC with a CD DSP, DRAM, and audio D/A converter, and other circuits.

Features

• MP3 Decoding Functions (MPEG audio standard [ISO/IEC 11172-3] layer 3)
- Decodes to a digital audio signal MP3 data decoded by the CD-ROM decoder and outputs that audio signal.
- Supports all bit rates, including variable bit rate operation.
- Supports the following sampling rates.
MPEG1 (Fs = 32 K, 44.1 K, 48 K)
MPEG2 (Fs = 16 K, 22.05 K, 24 K)
MPEG2.5 (Fs = 8 K, 11.025 K, 12 K)
- Can read out the MPEG header and ancillary data.
- Automatically mutes the signal on CRC errors using an MP3 CRC check function.
- External MPEG serial data input function supports memory card playback.
• CD-ROM Decoding Functions
- Supports CD-ROM modes 1 and 2 (forms 1 and 2)
- Faithfully reproduces data stored on CD-ROM discs using CD-ROM error correction functions.
- Header and sector management
- Supports playback speeds up to 4×.
- In addition to data buffering also supports C2 error flag buffering.
- Provides external serial output of decoded CD-ROM data.
• CD-DA Playback Functions (Shockproof support)
- Shockproof operation for about 180 seconds (compressed mode) when 64M DRAM is used.
- Shockproof function supports compressed, uncompressed, and data through modes.
- VCEC (variable speed) supports up to 4×-speed playback.
• Audio Signal Processing
- Serial audio signal output using LRCK, BCK, and DATA signals. (I²S format, either 16-bit or 20-bit precision PCM output, data-slot supports 16-bit, 24-bit, and 32-bit modes)
- Digital bass boost function (4 modes), attenuator function, and muting (-f, -12 dB)
- Provides a base clock (384 fs) output pin for use with external digital filters and D/A converters.
• DRAM Interface
- Supports the use of from 1M to 64M of external DRAM (EDO, 2CAS, 16-bit data bus memory)
- Supports allocation of a user area in DRAM during CD-ROM (MP3) playback.
• Package and Power Supply Voltage Specifications
- Package: Sanyo QFP80 (14 × 14) (unit: mm)
- Supply voltage
Internal power supply: 1.8 V (typical)
I/O power supply: 3.3 V (typical)
Analog system power supply: 3.3 V (typical)