28954-BRF-001-A Datasheet, PDF (1/4 Pages) M/A-COM Technology Solutions, Inc. – PCMx Voice P a i r Gain (VPG) Framer

network access products
Bt8954
PCMx Voice Pair Gain (VPG) Framer
Flexible Framer for VPG Market, Increasing
PSTN Switch Capacity Utilization
The Bt8954 framer forms the foundation for a complete
low-cost voice pair-gain system when combined with the
Conexant Bt8960 or RS8973.
Creating a voice PCM interface for Codecs, the Bt8954 combines
frame, overhead, and signaling information with the PCM payload
for transport over a DSL interface. And the Bt8954 supports from
2-18, 64 Kbps channels or up to 36, 32 Kbps ADPCM compressed
channels. When combined with the Bt8960, a 4-voice system is
possible with > 5km reach without ADPCM compression. This
allows high speed fax and data modems to operate above the 9600
baud limit compared with previous generation which uses 32 Kbps
ADPCM systems based on ISDN U-Interface chips. V.34 data and fax
modem performance is maximized through the use of single frame
strobes, low jitter PLL, and long reach Conexant HDSL technology.
Low Cost, High Performance
The Bt8954 is targeted at systems that support uncompressed
voice for high quality fax and data modem applications. Conexant
delivers low cost and high performance through a combination of
PCM bus interface, PCM clock generation, 18 individual Codec
strobes, and an internal slip buffer.
Since the generation of PCM clock and frame strobes is integrated
into the Bt8954, direct connection to low cost codecs such as the
Distinguishing Features
• Direct PCM Interface
• Supports popular PCM Codecs
• Payload of 2-18 64 Kbps voice channels
• 32 Kbps ADPCM supported
• 2.048 PCM clock generation
• 6.144, 8.192, and 20.48 MHz ADPCM
clock generation
• Slip buffer for singleTX/RX frame sync