Production Data
WM8770
DIGITAL FILTER CHARACTERISTICS
PARAMETER
ADC Filter
Passband
TEST CONDITIONS
MIN
TYP
MAX
0.4535fs
±0.01
UNIT
±0.01 dB
0
-6dB
0.5fs
Passband ripple
Stopband
dB
0.5465fs
-65
Stopband Attenuation
Group Delay
DAC Filter
f > 0.5465fs
dB
fs
22
Passband
±0.05 dB
0.444fs
-3dB
0.487fs
Passband ripple
Stopband
±0.05
dB
0.555fs
-60
Stopband Attenuation
Group Delay
f > 0.555fs
dB
fs
16
Table 16 Digital Filter Characteristics
DAC FILTER RESPONSES
0.2
0.15
0.1
0
-20
-40
0.05
0
-60
-0.05
-0.1
-0.15
-0.2
-80
-100
-120
0
0.5
1
1.5
2
2.5
3
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Frequency (Fs)
Frequency (Fs)
Figure 27 DAC Digital Filter Frequency Response
– 44.1, 48 and 96kHz
Figure 28 DAC Digital Filter Ripple – 44.1, 48 and 96kHz
0.2
0
0
-20
-40
-60
-80
-0.2
-0.4
-0.6
-0.8
-1
0
0.2
0.4
0.6
0.8
1
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Frequency (Fs)
Frequency (Fs)
Figure 29 DAC Digital Filter Frequency Response – 192kHz
Figure 30 DAC Digital filter Ripple - 192kHz
PD Rev 4.1 June 2005
45
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
