AKD4955-A Datasheet, PDF (42/89 Pages) Asahi Kasei Microsystems – AK4955 Evaluation Board Rev.3

[AKD4955-A]
13-1. Parameter Setting
(1) Please set a parameter of each Filter.
Parameter
Function
Sampling Rate
Sampling frequency (fs)
HPF
Cut Off Frequency
High pass filter cut off frequency
LPF
Cut Off Frequency
Low pass filter cut off frequency
FIL3
Cut Off Frequency
FIL3 cut off frequency
Filter type
Gain
EQ0
Pole Frequency
The selection of filter type
Gain
EQ0 Pole Frequency
Zero-point Frequency
EQ0 Zero-point Frequency
Gain
Gain2
5 Band Equalizer
EQ1-5 Center Frequency
EQ1-5 Band Width
EQ1-5 Gain
Gain
Gain2
EQ1-5 Center Frequency
EQ1-5 Band Width
EQ1-5 Gain
(Note 22)
(Note 23)
Setting Range
7350Hz ≤ fs ≤ 48000Hz
fs/10000 ≤ Cut Off Frequency
≤ (0.497 * fs)
fs/20 ≤ Cut Off Frequency
≤ (0.497 * fs)
fs/10000 ≤ Cut Off Frequency
≤ (0.497 * fs)
LPF or HPF
-10 ≤ Gain < 0 dB
fs/10000 ≤ Cut Off Frequency
≤ (0.497 * fs)
fs/10000 ≤ Cut Off Frequency
≤ (0.497 * fs)
-20 ≤ Gain < +12 dB
0 / +12 / +24 dB
0Hz ≤ Center Frequency < (0.497 * fs)
1Hz ≤ Band Width < (0.497 * fs)
-1 ≤ Gain < 3
Table 7.Parameter setting of [Filter Setting]
Note 22.A gain difference is a bandwidth of 3dB from center frequency.
Note 23.When a gain is “-1”, EQ becomes a notch filter.
(2) “LPF Enable”, “HPF Enable”, “HPFAD Enable”, “FIL3 Enable”, “EQ0 Enable”,
“EQ1”, “EQ2”, “EQ3”, “EQ4”, “EQ5” Please set ON/OFF of Filter with a check button.
When checked it, Filter becomes ON. When “Notch Filter Auto Correction” is checked, perform
automatic correction of the center frequency of the notch filter is executed.
<KM104703>
Figure 51.Filter ON/OFF setting button
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2011/08