VOCAL Announces Single-Processor VoIP-Analog Telephone Adapter Based on TMS320C55x DSP Generation from Texas Instruments

VOCAL Technologies released a single-processor design that will enable the development of equipment that allows homes and small businesses to add telephone lines to their broadband services. VOCAL's reference design for a Voice over IP (VoIP) analog telephone adapter (ATA) is based on the TMS320C55x digital signal processor (DSP) generation and analog technology from Texas Instruments.

Equipment that uses the VOCAL ATA design provides a way for service providers to connect consumers to their broadband IP networks.  In addition, these products may help bring VoIP telephone service to regions of the world where standard analog telephone service is poor or nonexistent.

The reference design can be used to create a variety of VoIP equipment including Ethernet phones and handheld wireless phones as well as ATAs. The design includes a software stack based on VOCAL's On-One DSP technology, an operating system designed for use in communications equipment.

VOCAL's ATA reference design incorporates TI's TMS320C5502 DSP alongside power management and analog logic devices. The C5502 device provides all the signal processing and control functionality needed to digitally encode and decode two conventional analog phone calls, then packetize them for transmission using the Internet Protocol (IP) over a broadband service provided by a cable or DSL modem. The programmable 200-megahertz (MHz)C5502 DSP from TI enabled VOCAL to integrate all of the necessary software functions and still have more than 25 percent of the DSP's performance left over for future product enhancements. By contrast, competing ATA designs that are based on RISC microprocessors cost more per operation for real-time signal processing but fail to provide the same high level of performance, making the end equipment more expensive yet less robust.

DSP performance and programmability enables a flexible design

The VOCAL ATA design also incorporates five high-performance analog power management and analog logic devices from TI to efficiently manage the ATA's power system. The TPS54350 SWIFT(TM) (Switcher With Integrated FET Technology) 3-A DC/DC converter provides greater than 90 percent efficiency with its accurate regulation of operating voltage down to 0.891 volts.

Other advanced TI devices in the ATA's bill of materials include the TPS79401 low-dropout linear regulator, SN74LVC1G66 analog switch, and SN74LVC244 and SN74LVC1G32 logic devices.

The VOCAL ATA design promotes cost-efficiency, fast time-to-market and ease of implementation for value-added features in a broad range of customer premise equipments (CPEs). The ATA solution supports up to two analog phone lines, two Ethernet ports and a public switched telephone network (PSTN) port that can be used in the event of a power outage or network disconnection. Design software includes a firewall, network address translation , end-user Web configuration, G.168 echo cancellation, adaptive jitter buffer and support for a variety of industry-standard vocoders, including G.711, G.723.1, G.726, G.729A/B and iLBC.

The 16-bit C5502 DSP which is at the heart of the VOCAL ATA design belongs to the industry's most power-efficient DSP platform, designed specifically to meet the requirements of communications systems. The device integrates 64 Kbytes of memory and interfaces to a variety of external memory types through a 32-bit enhanced memory interface. Other on-chip peripherals include a direct memory access (DMA) controller, three multi-channel buffered serial ports, host port interface and timers. Like all TI DSPs, the C5502 DSP is supported by Code Composer Studio(TM) Integrated Development Environment (IDE), the industry's most comprehensive IDE and suite of development tools for DSPs.

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