
Nippon Precision Circuits
OVERVIEW
The SM5841H is an 8-times oversampling (interpolation) 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
FEATURES
Functions
■ 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
■ 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
characteristics close to those of analog filters
■ Overflow limiter built-in
APPLICATIONS
■ Digital amplifiers
■ CD players
■ DAT players
■ DBS systems
■ PCM systems