Production Data
WM8945
DIGITAL FILTER CHARACTERISTICS
PARAMETER
ADC Filter
TEST CONDITIONS
MIN
TYP
MAX
0.454 fs
+/- 0.1
UNIT
Passband
+/- 0.1dB
-6dB
0
0.5fs
Passband Ripple
Stopband
dB
dB
0.546s
-60
Stopband Attenuation
DAC Normal Filter
Passband
f > 0.546 fs
+/- 0.03dB
-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
Note:
1. The Group Delays are quoted with the DSP SE1, SE2, and SE3 filters disabled. Enabling the DSP SE1, SE2, and SE3
filters will increase the Group Delay
PD, May 2011, Rev 4.1
157
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
