PSB7238 SIEMENS [Siemens Semiconductor Group], PSB7238 Datasheet - Page 23

• Manufacturer Part Number: PSB7238
• Description: Joint Audio Decoder-Encoder - Multimode
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

2.2.2
General
The uncompressed/compressed audio is applied to the interfaces as follows:
Uncompressed Audio
IOM-2 (transparent)
IOM-2 (transparent)
Host IF (interrupt handshake protocol)
“Transparent” means that data is received/transmitted in a time-slot without protocol.
1. Full Duplex G.728 Encoding/Decoding of One Audio Channel
Audio coding according to ITU-T G.728 fixed point recommendation using Low Delay
Code Excited Prediction (LD-CELP, 16 Kbit/s), offering toll quality audio. The postfilter
of the G.728 may be switched on (offering a higher quality impression) or off (providing
objective better S/N values).
2. Full Duplex G.723 Encoding/Decoding of One Audio Channel
Audio coding according to ITU-T G.723 recommendation using Multipulse Maximum
Likelihood Quantization (MP-MLQ, 6.3 Kbit/s) or Algebraic Code Excited Linear
Prediction (ACELP, 5.3 Kbit/s). The high pass filter, the postfilter and the Voice Activity
Detection of the G.723 may be independently switched on or off.
3. Full Duplex G.722 Encoding/Decoding of One Audio Channel
Audio coding for 7-kHz voice using the Sub-Band Coded Adaptive Differential PCM
(SB-ADPCM) algorithm according to the G.722 Recommendation.
4. Serial H.221/223 Oriented Audio Protocol
The PSB 7238 supports a serial H.221/223 oriented audio protocol for direct connection
to a Videocodec (VCP of 8 8 Inc.). This protocol provides an outband synchronization
of the audio bit streams by using block structures for the compressed audio data.
Semiconductor Group
Audio Functions and Supplementary Features
23
Compressed Audio
SAI (H.221/223 oriented audio protocol or
transparent)
Host IF (interrupt handshake protocol with
minimized interrupt load for the host)
Host IF (interrupt handshake protocol)
General Architecture and Functions
Data Sheet 1998-07-01
PSB 7238