STMicroelectronics Extends Class-D Amplifier Portfolio, Enabling High-End Home Multimedia to Look as Good as it Sounds

With the market for class-D amplifiers growing at around 50% per year, according to some industry estimates, ST’s TDA7498 targets performance-featured equipment such as DVD and Blu-ray players, home theater, active speakers, and docking stations. In such applications, the class-D amplifiers’ high energy efficiency and low heat generation support super-slim product styling and also save costs by eliminating bulky heatsinks and high-wattage power supplies. Class-D products already make up the majority of audio products, where small size, low power consumption and high audio outputs are fundamental demands.

“ST’s class-D portfolio delivers performance, size and cost advantages, leveraging the technology lead we have established over our competitors,” said Andrea Onetti, General Manager, Audio Division, within ST’s Home Entertainment and Displays Group. “The TDA7498 will enable our customers to create high-end multimedia products that look as good as they sound, which is increasingly important in today’s consumer markets.”

The TDA7498 is pin compatible with the TDA7492 2x50W amplifier, announced in September 2009, as well as the 2x80W TDA7498L and 100W mono TDA7498MV also now entering production. Pin compatibility between devices supports scalable product design using a common hardware platform to optimize development costs and time-to-market for new models. To simplify development of multichannel applications, the TDA7498 can also be externally synchronized, thus saving external components and avoiding cross-channel interference between channels. In all, ST now has single-chip class-D amplifier ICs from 2x3W to 2x100W.

ST’s class-D amplifier range is the first so far to use advanced BCD6S manufacturing technology, which allows analog, logic, and high-voltage functions to be built on a single chip. This simplifies design, increases reliability, reduces overall dimensions and saves bill-of-materials costs. Operating efficiency is also higher for a given chip size, compared to older processes, meaning that ST’s class-D ICs are typically smaller than competitors’ devices. A further advantage is that BCD6S allows complementary N- and P-type transistors in the output circuitry, which saves the external bootstrap capacitor and diode normally required with processes that support N-type transistors only.

Major specifications of the TDA7498:

* 10.3 x 7.5mm package outline
* Supply voltage range: 10V to 39V
* Up to 90% operating efficiency
* 10% THD + N @ full power into 6Ω speaker load; Vcc = 36V
* Pop-free mute control
* Four selectable gain settings: 25.6dB, 31.6dB, 35.1dB, 37.6dB

The TDA7498 is available immediately, packaged in a PowerSSO36 package, priced from $4.5 for 1000 pieces. Alternative pricing options are available for larger quantities.