Pre-Production
WM8786
DIGITAL FILTER CHARACTERISTICS
The WM8786 digital filter characteristics scale with sample rate.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
0.454fs
+/- 0.005
UNIT
ADC Sample Rate (Single Rate - 48Hz typically)
Passband
+/- 0.005dB
0
-6dB
0.5fs
Passband Ripple
Stopband
dB
0.546fs
-85
Stopband Attenuation
Group Delay
f > 0.546fs
dB
s
32/fs
0.5fs
ADC Sample Rate (Dual Rate - 96kHz typically)
Passband
+/- 0.005dB
0
0.454fs
-6dB
Passband Ripple
Stopband
+/- 0.005
dB
0.546fs
-85
Stopband Attenuation
Group Delay
f > 0.546fs
dB
s
32/fs
ADC Sample Rate (Quad Rate - 192kHz typically)
Passband
+/- 0.005dB
-3dB
0
0.25fs
0.45fs
0.5fs
-6dB
Passband Ripple
Stopband
+/- 0.005
dB
0.75
fs
Stopband Attenuation
Group Delay
f > 0.75fs
-85
dB
s
10/fs
3.7
High Pass Filter Corner
Frequency
-3dB
Hz
-0.5dB
10.4
-0.1dB
21.6
Table 1 Digital Filter Characteristics
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 3.0 December 2005
11
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