Datasheet
DRCHPF
from
Interface
to
Modulator
Digital
Volume
Ctrl
BiQuad
B
´
BiQuad
C
BiQuad
D
BiQuad
E
BiQuad
F
Interp.
Filter A
+
Beep
Gen.
Beep Volume Ctrl
´
IIR
Interp.
FilterC
BiQuad
D
BiQuad
C
BiQuad
B
BiQuad
A
IIR
to
modulator
Digital
Volume
Ctrl
from
Interface
´
Interp.
FilterC
DRCHPF
IIR
to
Modulator
Digital
Volume
Ctrl
BiQuad
D
BiQuad
C
BiQuad
B
BiQuad
A
from
Interface
´
TLV320AIC3120
www.ti.com
SLAS653A –FEBRUARY 2010–REVISED MAY 2012
5.6.1.2.7 Four Biquads, First-Order IIR, DRC, Filter C
Figure 5-25. Signal Chain for PRB_P21
5.6.1.2.8 Four Biquads, First-Order IIR, Filter C
Figure 5-26. Signal Chain for PRB_P22
5.6.1.2.9 Five Biquads, DRC, Beep Generator, Filter A
Figure 5-27. Signal Chain for PRB_P25
5.6.1.3 DAC User-Programmable Filters
Depending on the selected processing block, different types and orders of digital filtering are available. Up
to six biquad sections 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.
When the DAC is running, the user-programmable filter coefficients are locked and cannot be accessed
for either read or write.
However, the TLV320AIC3120 offers an adaptive filter mode as well. Setting page 8 / register 1, bit D2 = 1
turns on double buffering of the coefficients. In this mode, filter coefficients can be updated through the
host and activated without stopping and restarting the DAC. This enables advanced adaptive filtering
applications.
In the double-buffering scheme, all coefficients are stored in two buffers (buffers A and B). When the DAC
is running and adaptive filtering mode is turned on, setting page 8 / register 1, bit D0 = 1 switches the
coefficient buffers at the next start of a sampling period. This bit is set back to 0 after the switch occurs. At
the same time, page 8 / register 1, bit D1 toggles.
Copyright © 2010–2012, Texas Instruments Incorporated APPLICATION INFORMATION 45
Submit Documentation Feedback
Product Folder Link(s): TLV320AIC3120