SM5841H
NIPPON PRECISION CIRCUITS INC.
Audio Multi-function Digital Filter
OVERVIEW
The SM5841H is an 8-times oversampling (interpo-
lation) digital filter for digital audio reproduction
equipment. It accepts 16 or 18-bit input data, and
outputs data in 16, 18 or 20-bit format, making a
wide range of interfaces possible. It also features
digital deemphasis for 3 sampling frequencies, a
noise shaper to reduce quantization noise, a DC off-
set output and other circuits.
ORDERING INFOMATION
Device
SM5841HP
SM5841HS
Package
18pin DIP
22pin SOP
FEATURES
Functions
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2-channel processing
8-times (8fs) oversampling (interpolation)
Digital deemphasis (fs = 48/44.1/32 kHz)
Serial input data
2s complement, MSB first, 16/18-bit
Serial output data
2s complement, MSB first, 16/18/20-bit
1st-order noise shaper (for 16/18-bit output only)
256fs/384fs system clock selectable
Output data DC offset (approximately 0.8%)
ON/OFF control
TTL-compatible input/outputs
5 V (standard) supply
3.2 V operating voltage
Molybdenum-gate CMOS
Filter Characteristics
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3-stage DC FIR interpolation filter
1st stage (fs
→
2fs), 69-tap
2nd stage (2fs
→
4fs), 13-tap
3rd stage (4fs
→
8fs), 9-tap
IIR deemphasis filter for gain and phase character-
istics close to those of analog filters
Overflow limiter built-in
APPLICATIONS
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Digital amplifiers
CD players
DAT players
DBS systems
PCM systems
NIPPON PRECISION CIRCUITS—1
NPC [ NIPPON PRECISION CIRCUITS INC ]
