PSB7238 SIEMENS [Siemens Semiconductor Group], PSB7238 Datasheet - Page 6

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

Semiconductor Group
In a Videophone system using the 8 8 (formerly IIT) VCP (Video Codec and Multimedia
Communications Processor) the Siemens PSB 7238 can work standalone without the
need of external initialization. The default configuration of the JADE is such, that no host
is needed in this case and the full communication is done between the VCP and the
Siemens PSB 7238.
The voice compression algorithms are implemented by an embedded 16-bit fixed point
Digital Signal Processor with all memories internal and no external memory needed.
Integration of these and other features, as well as perfectly matched interfaces with other
ICs allows for the implementation of highly optimized, low cost system solutions e.g. for
Videophones, Data-over-voice and Channel Multiplexing equipment.
For system integration, two serial HDLC/transparent data channels are implemented
which can be serviced by an attached host (or the on-chip DSP). System functions and
communication between the chip and an external controller is supported by a full-duplex
256-byte on-chip mailbox communication memory.
The circuit is offered in a Quad Flat Pack package with 100 pins (P-TQFP-100: size
14
Note: This Data Sheet gives a thorough description of the functions and hardware that
14 mm, pitch 0.5 mm, height 1.4 mm).
forms the base of PSB 7238. It includes information (e.g. External Memory
Interface) that is not needed for the PSB 7238 as a “ ready to use plug and play ”
G.728/G.723/G.722/G.711 audio compression device.
6
Data Sheet 1998-07-01
Introduction
PSB 7238