SM5843A
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1
NIPPON PRECISION CIRCUITS INC.
Audio Multi-function Digital Filter
OVERVIEW
The SM5843A
×
1 is a multi-function digital filter IC,
fabricated using NPC’s Molybdenum-gate CMOS
process, for digital audio reproduction equipment. It
features 8-times oversampling (interpolation), digital
deemphasis and soft muting functions. It accepts 16,
18, or 20-bit input data, and outputs data in 18 or 20-
bit format. It operates using either a 384fs or 256fs
system clock.
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5 V supply
Crystal oscillator circuit built-in
TTL-compatible input/outputs
28-pin plastic DIP and SOP
Molybdenum-gate CMOS
APPLICATIONS
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CD players
DAT players
PCM systems
FEATURES
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Filter configuration (2-channel processing)
• 8-times oversampling (interpolation)
- 3-stage FIR configuration
• Deemphasis filter
- IIR filter configuration for correct gain and
phase characteristics
- 2-channel independent ON/OFF control
- 32/44.1/48 kHz sampling frequency (fs)
• 21
×
22-bit parallel multiplier/25-bit
accumulator for high precision
• Overflow limiter
2 oversampling filter characteristics
• Sharp roll-off characteristic (response 1)
-
≤
±0.00005 dB passband ripple (0 to
0.4535fs)
-
≥
110 dB stopband attenuation (0.5465fs to
7.4535fs)
• Slow roll-off characteristic (response 2)
-
≤
±0.00003 dB passband ripple (0 to 0.235fs)
-
≥
77 dB stopband attenuation (0.745fs to
7.255fs)
Soft muting
Digital attenuator
Input data format
• 2s complement, MSB first
- LR alternating, 16/18/20-bit serial, trailing
data
- LR alternating, 20-bit serial, leading data
- LR simultaneous, 20-bit serial, leading data
Output data format
• 2s complement, MSB first, LR simultaneous
• 18/20-bit serial
• BCKO burst (NPC format)
Dither processing ON/OFF control
Jitter-free/Sync mode selectable
256fs/384fs system clock selectable
• 21.2/14.2MHz
maximum
frequency
(384fs/256fs)
ORDERING INFOMATION
Device
SM5843AP1
SM5843AS1
Package
28pin DIP
28pin SOP
NIPPON PRECISION CIRCUITS—1
NPC [ NIPPON PRECISION CIRCUITS INC ]
