Overview

The SM5907AF is a compression and non compression type shock-proof memory controller LSI for compact disc players. The compression level can be set in 4 levels, and external memory can be selected from 4 options (4M, 4M× 2, 16M, 16M× 2). It operates from a 2.4 to 3.6 V supply voltage range.

Features

- 2-channel processing

- Serial data input

• 2s complement, 16-bit/MSB first, right-justified format

• Wide capture function (up to 3 × speed input rate)

- System clock input

• 384fs (16.9344 MHz)

- Shock-proof memory controller

• ADPCM compression method

• 4-level compression mode selectable

4-bit compression mode 2.78 s/Mbit

5-bit compression mode 2.22 s/Mbit

6-bit compression mode 1.85 s/Mbit

Full-bit non compression mode 0.74 s/Mbit

• 4 external DRAM configurations selectable

1 or 2 × 16M DRAM (4M × 4 bits, refresh cycle = 2048 cycle)

1 or 2 × 4M DRAM (1M × 4 bits)

- Microcontroller interface

• Serial command write and status read-out

• Data residual detector: 15-bit operation, 16-bit output

• Forced mute

- Extension I/O

Microcontroller interface for external control using 5 extension I/O pins

- +2.4 to +3.6 V operating voltage range

- Schmitt inputs

All input pins (including I/O pins) except CLK (system clock)

- Reset signal noise elimination

Approximately 3.8 µs or longer (65 system clock pulses) continuous LOW-level reset

- 44-pin QFP package (0.8 mm pin pitch)