PSB21473FV13XT Infineon Technologies, PSB21473FV13XT Datasheet - Page 380

• Manufacturer Part Number: PSB21473FV13XT
• Manufacturer: Infineon Technologies

Specifications of PSB21473FV13XT

• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3.135V
• Operating Supply Voltage (max): 3.6V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 144
• Lead Free Status / RoHS Status: Compliant

Data Sheet
Figure 20-7 Echo Cancellation Unit (Subband Mode) - Block Diagram
The subband mode can be enabled in five different submodes. These submodes offer a
trade-off between the maximum echo length and the functional units that can be run
simultaneously. All units that cannot be run simultaneously must be disabled before the
subband echo cancellation unit can be enabled. After the subband echo cancellation unit
is disabled, the parameters for the affected units must be rewritten by the
microcontroller.
For the optional Wiener filter, the maximum attenuation can be programmed with the
parameter WFATT. If the Wiener filter is enabled, it is only active while there is no speech
detected on the near side (microphone).
As shown in figure 20-7 the total attenuation provided by the speakerphone consists of
the attenuation G
suppression unit). In subband mode the attenuation G
by the adaptive filter) and G
If G
deactivated and G
such that G
Table 20-5 shows the registers associated with the subband echo cancellation unit. The
parameters AECATT, AECLIM, AECDTM, AECDTI and AECDTD have the same
meaning as in fullband mode. Note that the reported echo loss and parameter AECLIM
cover the complete echo cancellation unit including the Wiener filter.
loudspeaker
A
micro-
phone
already exceeds WFATT due to good adaptation then the Wiener filter is
C
=G
Analysis
A
+G
C
C
(provided by the echo cancellation unit) and G
=G
W
Control
never exceeds WFATT.
A
. Otherwise WFATT limits the attenuation G
W
(provided by the Wiener filter).
Analysis
NLMS
380
Filter
FIR
-
C
is further split into G
Synthesis
Digital Signal Processor
S
(provided by the echo
W
of the Wiener filter
WF
PSB 21473
line in
A
2003-03-31
(provided
INCA-D
line
out