PSB21373HV11XT Infineon Technologies, PSB21373HV11XT Datasheet - Page 110

• Manufacturer Part Number: PSB21373HV11XT
• Manufacturer: Infineon Technologies
• Type: PCMr

Specifications of PSB21373HV11XT

• Number Of Channels: 1
• Number Of Adc's: 1
• Number Of Dac's: 1
• Number Of Adc Inputs: 1
• Pin Count: 44
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

4.2.1
In the transmit direction a series of decimation filters reduces the sampling rate down to
the 8-kHz PCM-rate. These filters attenuate the out-of-band noise by limiting the transmit
signal to the voice band. The decimation stages end with a low-pass filter (LP).
If the tone generation unit is connected to the transmit direction (TGSR.DTMF = ’1’), a
special 2-kHz DTMF low-pass filter is placed in the transmit path. This filter guarantees
an attenuation of all unwanted frequency components, if DTMF signals are transmitted.
Additionally, it is possible to add a programmable tone signal to the transmit voice signal
(TGSR.TRX = ’1’).
The GX-gain adjustment stage is digitally programmable allowing the gain to be
programmed from + 6 to 0 dB in steps of
programmable but the transmission characteristics are only guaranteed in a specific
range, see table 10 and 11). Two bytes are necessary to set GX to the desired value.
After reset, the GX-gain stage is bypassed.
The transmit path contains a programmable high performance frequency response
correction filter FX allowing an optimum adaptation to different types of microphones
(dynamic, piezoelectric or electret). Twelve bytes are necessary to set FX to the desired
frequency correction function. After reset, the FX-frequency correction filter is bypassed.
Figure 59 shows the architecture of the FX/FR-filter.
A high-pass filter (HPX) is also provided to remove unwanted DC components.
In the voice data manipulation block a data format selection (A-law, -law, 8-bit linear,
16 bit linear), the masking of the 8-bit data and the data source selection for the two data
channels at the interface to the IOM handler is realized.
4.2.2
The incoming data from the IOM handler is similar to transmit direction processed by the
VDM block. A programmable sidetone gain stage GZ adds a sidetone signal to the
incoming voice signal. The sidetone gain can be programmed from – 54 to 0 dB within a
transmission characteristics are only guaranteed in a specific range, see table 10 and
11). Respectively two bytes are coded in the CRAM to set GZ to the desired value. After
reset, the GZ-gain stage is disabled (–
A high-pass filter (HPR) is also provided to remove disturbances from 0 to 50/60 Hz due
to the telecommunication network.
The frequency response correction filter (FR) is similar to the FX-filter allowing an
optimum adaptation to different types of loudspeakers or ear pieces. Twelve bytes are
necessary to set FR to the desired frequency correction function. After reset, the
FR-frequency correction filter is bypassed.
Data Sheet
1 dB tolerance range (values from –
Transmit Signal Processing
Receive Signal Processing
dB).
110
0.25 dB (values from –
dB to 12 dB are programmable but the
dB to 12 dB are
PSB 21373
2002-05-13