"The Manufacturer Says:"
Dallas — Texas Instruments Inc. (TI) developed its first digital amplifiers for the automotive market, which are based on its PurePath Class D amps for the home.

Specifically designed for automotive audio applications like head units and external amplifiers, the TAS5414 is a single-ended input amplifier and the TAS5424 has differential input.

TI's devices are said to be ultra-efficient four-channel digital audio Class D amplifiers. "With the TAS54x4 amplifiers, TI delivers 90 percent power efficiency at normal radio listening levels for automotive audio systems. Comparatively, two TAS54x4 amplifiers can provide eight channels of audio, while generating less heat than a four-channel Class AB-based system, enabling a whole new class of cost-effective eight-channel audio systems that are lighter, smaller and more power efficient than existing systems," said Jeff Akgul, TI's digital audio business manager. In addition, TI's new digital amplifiers also can be used with 2-ohm speakers to offer twice the output power of an AB amplifier into 4-ohm speakers, while generating less heat, he said.

With these automotive digital amplifiers, TI overcomes electromagnetic interference (EMI) at the source through innovative architecture and process advancements, such as an enhanced digital pulse-width modulation (PWM) topology, optimized gate drive technology and patented AM interference avoidance, Akgul said. These advancements make the TAS54x4 TI's first Class D amplifier to meet demanding automotive requirements, eliminating the need for expensive shielding and other EMI countermeasures, now making it possible for developers to bring the power advantages of digital amplification to automotive applications, he said.

By reducing heat dissipation, the TAS54x4 needs only a thin heat sink to spread heat compared to the large heat sinks and fans Class AB-based systems require, Akgul said. Radio head units with more functionality or more output channels can now be designed, eliminating the need for expensive external amplifiers and wire harnesses, he said.

Additionally, on-chip diagnostics simplify radio installation by testing all speaker connections, including tweeters, or short circuits created on the assembly line.

The TAS5414 and TAS5424 are designed to meet the defective parts per million (dppm) requirements of automotive OEMs. In addition, the amplifiers are TS16949 certified, which is the highest standard for automotive quality and reliability, according to Akgul. For an additional charge, TI also offers monitored burn-in during production.

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Currently sampling, the TAS5414 and TAS5424 are expected to be available for volume production in late 2006 and are scheduled to be AEC Q100 qualified at that time.

Pricing for the TAS5414IDKD in a 36-pin PSOP3 package is $9.75 in 1,000s. Pricing for the TAS5424IDKD, offered in a 44-pin PSOP3. is $10.50 in same quantities. Click here for additional information. Data sheets are not available yet.

Texas Instruments Inc., 1-800-477-8924, www.TI.com.

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