Complete Communications Engineering

HOUSTON (May 4, 2005) — A single-processor design announced today by VOCAL Technologies, Ltd. ( will enable the development of inexpensive equipments that allow homes and small businesses to add telephone lines to their broadband services. VOCAL’s innovative reference design for a Voice over IP (VoIP) analog telephone adapter (ATA) is based on a TMS320C55xTM low-power digital signal processor (DSP) platform and analog technology from Texas Instruments Incorporated (TI) (NYSE: TXN). TI’s DSP and analog technology helps VOCAL, a leading developer of software and hardware solutions for the communications industry, quickly deliver affordable VoIP connectivity for residential and commercial broadband customers.

Equipment that uses the VOCAL ATA design provides an inexpensive 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 inexpensive VoIP equipments, including Ethernet phones and handheld wireless phones as well as ATAs. The design includes a complete software stack based on VOCAL’s On-OneTM DSP technology, a highly efficient operating system designed specifically for use in communications equipment.

VOCAL’s ATA reference design incorporates TI’s TMS320VC5502 DSP alongside power management and analog logic devices. The C5502 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.

“The TI C5502 DSP gives us high-performance signal processing and control capabilities all in a single inexpensive device, along with a highly efficient compiler and easy to use tools,” said CTO Victor Demjanenko, Ph.D.. “VOCAL’s business is based on supplying communications algorithms, and we have more than a million lines of code in our product data base. TI’s strategy for DSP code compatibility lets us use existing software for the ATA and provides a migration path for continued software reuse in future products.”

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 SWIFTTM (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 V. 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 StudioTM Integrated Development Environment (IDE), the industry’s most comprehensive IDE and suite of development tools for DSPs.

“The VOCAL design demonstrates that TI customers are secure that they can re-use today’s code in tomorrow’s DSP-based applications because of TI’s commitment to code compatibility,” said Raj Agrawala, C5000 DSP marketing manager, TI. “With the industry’s largest portfolio of DSPs, meeting requirements from cost efficiency to high performance, TI makes it possible for developers to realize their visions for product innovation.”

About VOCAL Technologies, Ltd.
Founded in 1986, VOCAL Technologies, Ltd., is an industry leader in providing innovative telecommunications and networking solutions to a large base of international OEM customers. VOCAL has one of the industry’s largest data and telephony software modem libraries, and supports all major platforms including Texas Instruments, Analog Devices, ARM, MIPS, x86, Legerity, and StarCore cores. For more information,