WM8904
Pre-Production
DIGITAL FILTER CHARACTERISTICS
PARAMETER
ADC Filter
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Passband
+/- 0.05dB
-6dB
0
0.454 fs
+/- 0.05
0.5 fs
Passband Ripple
Stopband
dB
dB
0.546s
-60
Stopband Attenuation
DAC Normal Filter
Passband
f > 0.546 fs
+/- 0.05dB
-6dB
0
0.454 fs
+/- 0.03
0.5 fs
Passband Ripple
Stopband
0.454 fs
dB
dB
0.546 fs
-50
Stopband Attenuation
DAC Sloping Stopband Filter
Passband
F > 0.546 fs
+/- 0.03dB
+/- 1dB
-6dB
0
0.25 fs
0.25 fs
0.454 fs
0.5 fs
Passband Ripple
Stopband 1
0.25 fs
+/- 0.03
0.7 fs
dB
dB
dB
dB
0.546 fs
-60
Stopband 1 Attenuation
Stopband 2
f > 0.546 fs
f > 0.7 fs
0.7 fs
-85
1.4 fs
Stopband 2 Attenuation
Stopband 3
1.4 fs
-55
Stopband 3 Attenuation
F > 1.4 fs
DAC FILTERS
ADC FILTERS
Mode
Group Delay
16.5 / fs
Mode
Normal
Group Delay
16.5 / fs
Normal
Sloping Stopband
18 / fs
TERMINOLOGY
1. Stop Band Attenuation (dB) – the degree to which the frequency spectrum is attenuated (outside audio band)
2. Pass-band Ripple – any variation of the frequency response in the pass-band region
PP, Rev 3.3, September 2012
30
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
