Datasheet
TLV320AIC3110
SLAS647B –DECEMBER 2009–REVISED MAY 2012
www.ti.com
Table 5-20. ADC FIR Filter Coefficients (continued)
Filter FIlter Coefficient RAM Default (Reset) Values – Not Valid for the FIR Filter – Must
Coefficient Location Be Reprogrammed by User
Fir20 Page 4 / register 54 0x7FFF (decimal 1.0 – LSB value)
and page 4 / register 55
Fir21 Page 4 / register 56 0x0000
and page 4 / register 57
Fir22 Page 4 / register 58 0x0000
and page 4 / register 59
Fir23 Page 4 / register 60 0x0000
and page 4 / register 61
Fir24 Page 4 / register 62 0x0000
and page 4 / register 63
5.4.4.4 ADC Digital Decimation Filter Characteristics
The TLV320AIC3110 offers three different types of decimation filters. The integrated digital decimation
filter removes high-frequency content and downsamples the audio data from an initial sampling rate of
AOSR × f
S
to the final output sampling rate of f
S
. The decimation filtering is achieved using a higher-order
CIC filter followed by linear-phase FIR filters. The decimation filter cannot be chosen by itself; it is implicitly
set through the chosen processing block.
The following subsections describe the properties of the available filters A, B, and C.
5.4.4.4.1 Decimation Filter A
This filter is intended for use at sampling rates up to 48 kHz. When configuring this filter, the oversampling
ratio of the ADC can either be 128 or 64. For highest performance, the oversampling ratio must be set
to 128.
Filter A can also be used up to 96 kHz with an AOSR of 64.
Table 5-21. ADC Decimation Filter A, Specification
Parameter Condition Value (Typical) Unit
AOSR = 128
Filter gain pass band 0 … 0.39 f
S
0.062 dB
Filter gain stop band 0.55 … 64 f
S
–73 dB
Filter group delay 17/f
S
s
Pass-band ripple, 8 ksps 0 … 0.39 f
S
0.062 dB
Pass-band ripple, 44.1 ksps 0 … 0.39 f
S
0.05 dB
Pass-band ripple, 48 ksps 0 … 0.39 f
S
0.05 dB
AOSR = 64
Filter gain pass band 0 … 0.39 f
S
0.062 dB
Filter gain stop band 0.55 … 32 f
S
–73 dB
Filter group delay 17/f
S
s
Pass-band ripple, 8 ksps 0 … 0.39 f
S
0.062 dB
Pass-band ripple, 44.1 ksps 0 … 0.39 f
S
0.05 dB
Pass-band ripple, 48 ksps 0 … 0.39 f
S
0.05 dB
Pass-band ripple, 96 ksps 0 … 20 kHz 0.1 dB
36 APPLICATION INFORMATION Copyright © 2009–2012, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: TLV320AIC3110