SM5902AF

SM5902AF NIPPON PRECISION CIRCUITS INC. compression and non compression type shock-proof memory controller Overview The SM5902 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 (1M, 4M, 4M × 2, 16M). Digital attenuator, soft mute and related functions are also incorporated. It operates from a 2.4 to 5.5 V wide 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 × 16M DRAM (4M × 4 bits, refresh cycle = 2048 cycle) 1 × or 2 × 4M DRAM (1M × 4 bits) 1 × 1M DRAM (256k × 4 bits) ⋅ DRAM at 5V operation is usable for Low-voltage operation - Compression mode selectable - Microcontroller interface ⋅ Serial command write and status read-out ⋅ Data residual detector: 15-bit operation, 16-bit output ⋅ Digital attenuator 8-bit setting ⋅ Soft attenuator function Noiseless attenuation-level switching (256- step switching in 23 ms max.) ⋅ Soft mute function Mute ON in 23 ms max. Direct ...