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ManualsBrandsTEXAS INSTRUMENTS ManualsData collecting ICsData acquisition IC - ADC 16 Bit DSBGA 16
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1
st
Order
IIR
x
AGC
Gain
Compen
sation
AGC
FilterC
H
E
H
D
H
C
H
B
H
A
FromDelta-Sigma
Modulatoror
DigitalMicrophone
From
DigitalVol.Ctrl
To AnalogPGA
To Audio
Interface
1
st
Order
IIR
x
AGC
Gain
Compen
sation
AGC
FilterC
25-TapFIR
FromDelta-Sigma
Modulatoror
DigitalMicrophone
From
DigitalVol.Ctrl
To AnalogPGA
To Audio
Interface
1
0 1
15 1
1
N + N z
H(z) =
2 D z
-
-
-
TLV320ADC3001
www.ti.com
SLAS548C –OCTOBER 2008– REVISED APRIL 2011
Five Biquads, First-Order IIR, AGC, Filter C
Figure 41. Signal Chain for PRB_R14 and PRB_R17
25-Tap FIR, First-Order IIR, AGC, Filter C
Figure 42. Signal for PRB_R15 and PRB_R18
User-Programmable Filters
Depending on the selected processing block, different types and orders of digital filtering are available. A
first-order IIR filter is always available, and is useful to filter out possible dc components of the signal efficiently.
Up to five biquad sections, or alternatively up to 25-tap FIR filters, are available for specific processing blocks.
The coefficients of the available filters are arranged as sequentially indexed coefficients in two banks. If adaptive
filtering is chosen, the coefficient banks can be switched in real time.
The coefficients of these filters are each 16-bits wide, in 2s-complement and occupy two consecutive 8-bit
registers in the register space. Table 7.
First-Order IIR Section
The transfer function for the first-order IIR filter is given by Equation 2.
(2)
The frequency response for the first-order IIR section with default coefficients is flat at a gain of 0 dB.
Table 7. ADC 1st order IIR Filter Coefficients
Filter FIlter Coefficient ADC Coefficient, Left Channel ADC Coefficient, Right Channel
N0 C4 (page 4 / register 8 and page 4 / C36 (page 4 / register 72 and page 4 /
register 9) register 73)
N1 C5 (page 4 / register 10 and page 4 / C37 (page 4 / register 74 and page 4 /
First-order IIR
register 11) register 75)
D1 C6 (page 4 / register 12 and page 4 / C38 (page 4 / register 76 and page 4 /
register 13) register 77)
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