OVERVIEW
The SM5847AF is a 4/8-times oversampling (inter polation), 2-channel, linear-phase FIR, multi-function digital filter for digital audio reproduction equipment. It features independent left and right channel digital deemphasis filters and soft muting function.
FEATURES
■ Left/right-channel (2-channel processing)
■ 4-times/8-times oversampling (interpolation)
• 8-times interpolation filter
- 3-stage linear-phase FIR configuration
1st stage (fs to 2fs): 169-tap
2nd stage (2fs to 4fs): 29-tap
3rd stage (4fs to 8fs): 17-tap
- ≤±0.00002 dB passband ripple (0 to 0.4535fs)
- ≥117 dB stopband attenuation (0.5465fs to 7.4535fs)
• 4-times interpolation filter
- 2-stage linear-phase FIR configuration
1st stage (fs to 2fs): 169-tap
2nd stage (2fs to 4fs): 29-tap
- ≤±0.00002 dB passband ripple (0 to 0.4535fs)
- ≥116 dB stopband attenuation (0.5465fs to 3.4535fs)
■ Digital deemphasis
• IIR filter configuration
• fs = 32kHz, 44.1kHz, 48kHz
• 2-channel independent ON/OFF control
■ 26 ×24-bit parallel multiplier/32-bit accumulator
■ Overflow limiter
■ Soft muting
• 2-channel independent ON/OFF control
■ Input data format
• 2s complement, MSB first
• 3 selectable formats
- LR alternating, 16/18/20/24-bit serial, righ justified data
- LR alternating, 24-bit serial, left-justifie data
- LR simultaneous, 24-bit serial, left-justifie data
■ Output data format
• 2s complement, MSB first, LR simultaneous
• 18/20/22/24-bit serial
• BCKO burst (NPC format)
■ Dither round-off processing
• Dither round-off ON/OFF selectable
■ 25-bit internal data word length
■ Internal system clock
• 192fs/256fs selectable
• Maximum operating frequency
192fs mode: 37 MHz max (5 V)
20.7 MHz max (3 V)
256fs mode: 27.6 MHz max (5 V)
25 MHz max (3 V)
■ Jitter-free function
• Jitter-free/Sync mode selectable
■ Crystal oscillator circuit built-in
■ 3 to 5 V supply
■ 44-pin plastic QFP
■ CMOS process