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.