This specification describes the Bt8110 and Bt8110B multichannel ADPCM processor CMOS integrated circuits that implement Adaptive Differential Pulse-Code Modulation (ADPCM) encoding and decoding. The fixed-rate coding algorithms include those specified in ANSI Standard T1.303-1989. These algorithms are identical to those in ITU-T Recommendations G.726 and G.727. These circuits also implement the variable-rate or embedded codes specified in ANSI Standard T1.310-1991 and ITU-T Recommendation G.727.

A single ADPCM processor integrated circuit can provide 24 or 32 full-duplex channels of ADPCM processing (encoding and decoding). In some applications, two circuits can be combined to provide 48 or 64 full-duplex channels. Both A-law and µ-law PCM translations are provided.

Distinguishing Features

• Bt8110B offers internal ROM

• 24 or 32 full-duplex channel capacity (48 or 64 channels with two processors)

• 2-, 3-, 4- and 5-bit quantization dynamically selectable on a channel-by-channel, frame-by-frame basis

• Transparent channel operation

• Two control modes available: microprocessor and hardware.

• Direct framer interface for both T1 and E1 signal formats

• Supports the optimal RESET function described in the algorithm standards

• Supports even-bit inversion of A-law inputs and outputs (required by ITU-T Recommendations G.726, and G.727)

• Minimum throughput delay

• Pin compatible with Bt8110

• 8 mw per-channel, low-power CMOS

Applicable Standards

• ANSI T1.302-1987

• ANSI T1.303-1989

• ANSI T1.310-1991

• ITU-T G.726, G.727

• ANSI T1.501-1994

• ANSI T1Y1 Technical Reports #3 and #10

Applications

• T1/E1 Transcoders

• T1/E1 Multiplexers

• Personal Communications Systems:

  Digital European Cordless Telecommunications (DECT), Personal Access Communications System (PACS)

• Wireless Local Loop

• Voice PairGain

• DCME Systems

• Speech Processing/Recording

• Voice Mail/Packetization

• Voice over ATM/Frame Relay