SM5950AM Datasheet, PDF (2/20 Pages) Nippon Precision Circuits Inc – Asynchronous Sample Rate Converter

SM5950AM
FEATURES
Interfaces
I Input data format
• 2s-complement, MSB-first, L/R alternating serial
data
• IIS/non-IIS formats
Format
16-bit MSB-first right-justified
20-bit MSB-first right-justified
24-bit MSB-first right-justified
MSB-first left-justified
(leading 16 bits valid data)
IIS (leading 16 bits valid data)
IMOD0 IMOD1 IISI
L
L
L
H
L
L
L
H
L
H
H
L
H or L H or L
H
L = Low input level, H = high input level
I Output data format
• 2s-complement, MSB-first, L/R alternating serial
data
• Bit clock continuous (64fso)
Format
OMOD0 OMOD1 IISO
16-bit MSB-first right-justified
L
L
L
20-bit MSB-first right-justified
H
L
L
24-bit MSB-first right-justified
L
H
L
MSB-first left-justified (16-bit output) H
H
L
IIS (16-bit output)
H or L H or L
H
L = Low input level, H = high input level
Structure
I Silicon-gate CMOS process
Applications
I Digital audio equipment-interface sample rate
conversion
• AV amplifier, CD-R/RW, DAT, MD, DVC
I Recording/editing equipment sample rate conver-
sion
Converter Performance
I Internal data word length: 20 bits
I Deemphasis filter characteristics (IIR filter)
• ± 0.03dB gain deviation from ideal filter char-
acteristic
I Anti-aliasing LPF characteristics (6 types of FIR
filter)
• Output/input sample rate conversion ratio auto-
matic filter select (6 FIR filters)
1. Up converter LPF
1.0 to 2.205 times
2. Down converter LPF I
about 0.92 times: 48.0kHz to 44.1kHz
3. Down converter LPF II
about 0.73 times: 44.1kHz to 32.0kHz
4. Down converter LPF III
about 0.67 times: 48.0kHz to 32.0kHz
5. Down converter LPF IV
about 0.50 times: 96.0kHz to 48.0kHz
6. Down converter LPF V
about 0.45 times: 96.0kHz to 44.1kHz
- Passband ripple: ± 0.0001dB
- Stopband attenuation: > 98dB
I Converter insertion quantization noise level
• Internal calculation (quantization) noise
: ≤ – 96dB
• Output round-off noise:
- 16-bit output mode : – 98dB
- 20-bit output mode : – 122dB
- 24-bit output mode : – 146dB
• Output S/N ratio (theoretical values)
Output signal
word length
16 bits
20 bits
24 bits
S/N ratio
16-bit input 20-bit input 24-bit input
– 92.5dB – 94.0dB – 94.0dB
– 93.9dB – 96.2dB – 96.2dB
– 93.9dB – 96.2dB – 96.2dB
NIPPON PRECISION CIRCUITS INC.—2