OVERVIEW
The SM5849AF is a digital audio signal, asynchronous sample rate converter LSI. It supports 16/20/24-bit word length input data, 16/20/24-bit word length output data, 2kHz to 100kHz input sample rate range, and 4kHz to 200kHz output sample rate range. It also features a built-in digital deemphasis filter and digital attenuator.

FEATURES
Functions
■ Left/right-channel processing (stereo)
■ 2 to 100kHz input sample rate range (fsi)
■ 4 to 200kHz output sample rate range (fso)
■ 0.45 to 2.2-times variable sample rate conversion ratio (fso/fsi)
■ Asynchronous input and output timing (clock inputs)
■ System clock inputs (input and output clocks inde pendent)
   • 256fsi or 384fsi input system clock select
   • 256fso or 384fso output system clock select
■ Deemphasis filter
   • IIR-type filter
   • 44.1, 48 or 32kHz
■ Digital attenuator
   • 11-bit data, 1025 levels
   • Smooth attenuation change
   • +12dB gain shift function
■ Direct mute function
■ Through mode operation
   • Direct connection from input to output
■ Output data clocks (LRCO, BCKO)
   • Slave mode: external input
   • Master mode: output system clock generated internally
■ Dither round-off processing
   • Dither round-off ON/OFF selectable
■ 3.3V single supply
■ 80-pin QFP
■ Silicon-gate CMOS process

Filter Characteristics and Converter Efficiency
■ 24-bit internal data word length
■ Deemphasis filter characteristics (IIR filter)
   • ±0.03dB gain deviation from ideal filter charac teristics
■ Anti-aliasing LPF characteristics
   • Output/input sample rate conversion ratio automatic filter select (6 FIR filters)
      - Up converter LPF
         1.0 to 2.2 times
      - Down converter LPF I
         0.92 times: 48.0 to 44.1kHz
      - Down converter LPF II
         0.73 times: 44.1 to 32.0kHz
      - Down converter LPF III
         0.67 times: 48.0 to 32.0kHz
      - Down converter LPF IV
         0.5 times: 48.0 to 24.0kHz
      - Down converter LPF V
         0.45 times: 48.0 to 22.1kHz
   • ±0.00005dB passband ripple
   • > 110dB stopband attenuation
■ Converter noise levels
   • ≤ −110dB internal calculation (quantization) noise
   • −98dB (16-bit output), −122dB (20-bit output), and −146dB (24-bit output) word rounding noise
■ Output S/N ratio (theoretical values)

Interfaces
■ Input data format
   • 2s-complement, L/R alternating, serial
   • IIS/non-IIS format
■ Output data format
   • 2s-complement, MSB first, L/R alternating, serial
   • Continuous bit clock
  
APPLICATIONS
■ Digital audio equipment-interface sample rate conversion (AV amplifiers, CD-R, DAT, MD and 8mm VTRs)
■ Commercial recording/editing equipment sample rate conversion