Introduction

Lucent Technologies’ Phone-On-A-Chip IP Solution is a highly integrated set of IC chips that form the basic building blocks for an internet protocol telephone (IPT), residing on a local area network (LAN).

The IPT presently consists of two ICs—the T8301 (IPT_DSP) and the T8302 (IPT_ARM*).

The T8301 provides the audio processing engine for voice compression and decompression, speakerphone echo cancellation, digital-to-analog and analog-to-digital converters, low-pass filters, and amplifiers to drive standard business telephone handsets and speakerphone hardware.

The general-purpose processor chip T8302 controls system I/O (Ethernet, USB, IrDA, etc.) and provides general telephone control features (LED control, keypad button scanning, LCD module interface, etc.).

Features

■ DSP1627 core with bit manipulation unit.

■ DSP clock speeds up to 80 MHz.

■ Instruction ROM, 32K x 16 (zero wait-state at 80 MHz).

■ Dual-port RAM, 6K x 16 (zero wait-state at 80 MHz).

■ Internal SRAM, 16K x 16 (single wait-state at 80 MHz).

■ 16-bit analog-to-digital converter.

■ Programmable gain amplifier on audio input.

■ Fixed gain differential microphone input.

■ Analog input SRAM buffer, 512 x 16.

■ Timed DMA for analog input SRAM.

■ Two 16-bit digital-to-analog converters.

■ Independent simultaneous speaker and handset outputs.

■ Two integrated differential speaker driver outputs.

■ Two analog output SRAM buffers, 512 x 16 each.

■ Two timed DMA outputs for simultaneous handset and speaker audio output.

■ Low-pass filtering on audio inputs and outputs.

■ Serial I/O interface.

■ General-purpose timer counter.

■ Bit I/O interface.

■ JTAG test and debugging control.

■ Implementation in 0.35 µm, 5 V silicon technology.

■ Packaged in 100-pin TQFP.