cs5378 Cirrus Logic, Inc., cs5378 Datasheet - Page 46

• Manufacturer Part Number: cs5378
• Description: Low-power Single-channel Decimation Filter
• Manufacturer: Cirrus Logic, Inc.

DS639F1
FIR1 – Single stage, fixed decimate by 4
FIR2 – Single stage, fixed decimate by 2
Combined SINC + FIR digital filter specifications
SINC + FIR filters
FIR2
Output
Word
Rate
4000
2000
1000
500
333
250
200
125
100
50
40
25
20
10
5
1
Coefficient set 0: linear phase decimate by 4, 48 coefficients
Coefficient set 1: minimum phase decimate by 4, 48 coefficients
Coefficient set 0: linear phase decimate by 2, 126 coefficients
Coefficient set 1: minimum phase decimate by 2, 126 coefficients
Passband ripple less than +/- 0.01 dB below 40% f
Transition band -3 dB frequency at 42.89% f
Stopband attenuation greater than 130 dB above 50% f
SINC
Deci-
mation
SINC droop compensation filter
Brick wall low-pass filter, flat to 40% f
12800
64000
1280
1600
2560
3200
6400
128
192
256
320
512
640
16
32
64
FIR1
Deci-
mation
Table 14. FIR Filter Characteristics
Figure 26. FIR Filter Stages
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
FIR2
Deci-
mation
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
Total
Deci-
mation
102400
512000
10240
12800
20480
25600
51200
1024
1536
2048
2560
4096
5120
128
256
512
s
Passband
Ripple
( ± dB)
s
0.0042
0.0045
0.0040
0.0041
0.0080
0.0064
0.0043
0.0046
0.0040
0.0040
0.0040
0.0040
0.0036
0.0036
0.0036
0.0029
s
s
Stopband
Atten-
uation
(dB)
130.38
130.38
130.42
130.42
130.45
130.43
130.44
130.42
130.43
130.43
130.44
132.98
130.43
130.43
130.43
134.31
CS5378
46