PSB2163T-V31TR Infineon Technologies, PSB2163T-V31TR Datasheet - Page 143

• Manufacturer Part Number: PSB2163T-V31TR
• Description: IC AUDIO RINGING CODEC 28-PDSO
• Manufacturer: Infineon Technologies
• Series: ARCOFI®r

Specifications of PSB2163T-V31TR

• Function: CODEC Filter
• Interface: IOM-2, PCI, Serial
• Number Of Circuits: 1
• Voltage - Supply: 5V
• Current - Supply: 900µA
• Power (watts): 1mW
• Operating Temperature: -25°C ~ 80°C
• Mounting Type: Surface Mount
• Package / Case: DSO-28
• Includes: Activation and Deactivation, B-Channel and D-Channel HDLC Controllers, D-Channel Priority Handler, Monitor Channel Handler
• Lead Free Status / RoHS Status: Request inventory verification / Request inventory verification
• Other names: PSB2163T-V31INTR; PSB2163T-V31TR

Semiconductor Group
(decay speed in ms/dB). Therefore the transition into idle mode is very smooth and
hardly noticeable.
Starting from idle mode, depending on the first speech detector recognizing speech, the
device switches immediately into transmit or receive mode. The speed for this immediate
mode switching is determined by the parameter SW (switching time).
Table 2
Parameters for Switchable Attenuation / Speed of Transitions
Parameter
ATT
TW
DS
SW
Note, that the parameters explained above are not responsible for the decision, when to
change a mode. Any changes made for TW, DS, SW only affect the speed of the
transitions between the modes and are not responsible for example for the capability of
recognizing speech and switching the mode. This is handled by the speech detectors
and the speech comparators.
2.5
Both speech detectors have the same structure. For almost every application the
standard parameter set can be used, and there is usually no need for a change except
for the parameters described in the paragraph "processing of continuous tones".
Figure 5 shows the block diagram of the speech detector with all programmable
parameters. Basically, the speech detector makes use of the burst characteristic of
speech, that means, every fast change in signal amplitude compared to the average
signal level is recognized as speech. This is done by averaging the input signal with a
low pass filter (LP2) and comparing the output signal of this low pass with the input signal
itself.
Background Noise Monitor
Background noise monitoring is realized by the low pass LP2. Background noise can be
regarded as approximately stationary from its averaged power. Since only a difference
The Speech Detector
Typical Value
10...40 dB
144 ms
99 ms/dB
0.6 ms/dB
Meaning
Amount of switchable attenuation that will always be
present in receive and/or transmit path (depending on
mode: transmit, receive, idle).
Wait time that passes before the transition from receive
or transmit mode into idle mode starts.
Decay speed that determines how fast the switchable
attenuation changes when going into idle mode.
Switching time for the transition out of idle mode into
transmit or receive mode or for the direct transition from
receive mode into transmit mode and vice versa.
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Speakerphone Implementation