PEF 20954 HT V1.1 Infineon Technologies, PEF 20954 HT V1.1 Datasheet - Page 17

• Manufacturer Part Number: PEF 20954 HT V1.1
• Description: IC ECHO CANCELLER DGTL TQFP144
• Manufacturer: Infineon Technologies

Specifications of PEF 20954 HT V1.1

• Function: Smart Integrated Digital Echo Canceller (SIDEC)
• Interface: PCM, Serial, UCC
• Number Of Circuits: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 350mA
• Power (watts): 900mW
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 144-LFQFP
• Includes: Double Talk Detection
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: PEF20954HTV1.1; SP000007505

PEB 20954
PEF 20954
Introduction
VoIP Gateway
IP Network
PSTN
(ATM,Frame Relay
SIDEC
,Ethernet)
PEB 20954
VoIP Gateway
Figure 3
SIDEC in a Voice over IP Gateway
An emerging market in the telecom industry is “Voice Over IP”. Due to the long delay
echo cancellation is required. The delay is introduced through packetizing and voice
compression. The SIDEC handles different functions in a Voice over IP gateway, such
as Voice Detection, Voice Activity Detection, Comfort Noise and A-law u-law conversion
regarding G.711.
In a gateway the SIDEC points into the PSTN network as shown in
Figure
3. The echo
itself is generated by the hybrid in the PSTN cloud. Before the voice signal from the
POTS gets packetized into ATM, FR or Ethernet cells the echo is being cancelled by the
SIDEC.
For a high voice quality in “Voice Over IP” environment echo cancellation is a major
requirement.
Data Sheet
17
Rev. 2, 2004-07-28