TI has introduced a suite of DSP hardware and software solutions
that will help clear the way for simultaneous voice and data wireless
transmission. The product portfolio, which will help lower power
dissipation and cut consumer costs by reducing chip count, includes
two DSPs for wireless communications and offers complementary
standard-specific mixed-signal devices and GSM software modules.
According to Gilles Delfassy, general manager of TI's worldwide wireless communications business unit, the new TMS320C545 and TMS320C546 offer the first single-DSP solutions for enhanced cellular standards, such as half-rate GSM. "Previously, these complex systems required at least two DSPs, plus external memory enhancements," said Delfassy. "Because the 'C545 and 'C546 are programmable, they can also accommodate accepted standards such as IS-54, IS-136, Personal Digital Cellular (PDC), and GSM."
The 'C545 and 'C546 memory configuration makes them ideally-suited to half-rate applications. Both DSPs include 6K x 16 words of on-chip RAM, 48K x 16 words of ROM, and can operate at either 2.7 or 5 volts. Also included are three different power-down modes that can cut power dissipation to as little as one milliwatt. Their ability to execute single-instruction operations that take the place of as many as three general-purpose processor instructions also reduces power requirements.
In conjunction with the 'C545 and 'C546, TI has introduced the industry's first software for half-rate GSM communications, designed like TI's full-rate GSM software to help shorten time to market for efficient, cost-effective GSM applications. Also, TI has disclosed the development of new baseband interface devices for GSM and IS-136 standards that extend battery life by reducing power dissipation.
The half-rate GSM software modules run on the 'C545 and 'C546 and perform a variety of functions such as voice coding and decoding, demodulation, encryption, channel coding and decoding, interrupt handling, and control. The software requires only 27 MIPS of processing capacity, allowing ample performance for other features such as voice dialing, speaker phone, and noise cancellation.
Delfassy said that while half-rate and enhanced full-rate standards are now used on an experimental basis, it is anticipated that service providers will soon adopt them. "Half-rate applications allow a provider to pack twice as many conversations into the available bandwidth, which means a company can serve more customers without additional transmission capacity," he said. "This means a provider can minimize the need for extra transmission towers, which is a problem in some areas."
The 'C545 and 'C546 are now sampling and in production. US pricing for the 'C545 is $28 each (128-pin TQFP) at 250,000-piece quantities. The 'C546 is $26 each (100-pin TQFP) at 250,000-piece quantities. Neither device is available through distribution at this time.