Class D amps claim top sound quality
A new family of audio amplifiers combines the space- and heat-saving advantages of Class-D amplification with advanced signal processing technology to deliver dramatic improvements in sound quality
A new family of audio amplifiers combines the space- and heat-saving advantages of Class-D amplification with ADI's advanced audio signal processing technology to deliver dramatic improvements in sound quality. Analog Devices' Class-D audio amplifiers outperform competing devices on the key performance requirements of audio fidelity and EMI, previously the most difficult to attain using a Class-D architecture.
No other Class-D device has been able to achieve less than 0.005% THD+N (total harmonic distortion plus noise) and up to 2 x 40W output power while reducing heat dissipation by 50% in a one-chip solution.
This unique combination of features resolves design challenges in consumer applications such as HDTV and home theatre systems, which demand high performance audio from the smallest possible sound systems.
EMI reduction prevents interference with other electronic equipment, which is particularly important in the design of automotive audio systems.
The AD199x Class-D amplifiers outperform competing PWM-based Class-D schemes by using a highly-integrated single-chip design which features a 'high modulation factor' sigma-delta architecture, configured in a closed-loop implementation with a high power output stage.
Ultimately, this enables higher audio fidelity in half the space of competing devices and meets the demands of next-generation electronics, such as thin flat panel TVs and multichannel surround sound car stereos.
'New consumer electronics applications, especially advanced TVs, are designed as much for their aesthetic appeal as their audio/video performance'.
'Class-D, with its inherent space and heat advantages, is an important enabling technology', said Dick Meaney, Vice President of the Precision Convertor Group at Analog Devices 'Analog Devices' new audio amplifiers take Class-D technology to the next level without compromising sound quality'.
'Leading the industry in high performance and EMI reduction, the devices are the best choice for audio amplification in the demanding car audio market'.
The AD199x amplifiers deliver audiophile sound quality (THD less than 0.005%; SNR better than 101dB; and PSRR better than 65dB) with 50% lower heat dissipation than traditional linear amplifiers.
The devices' breakthrough performance is achieved through Analog Devices' closed-loop, mixed-signal integration of 7th order sigma-delta modulator technology with high-power output drive circuitry and bridge circuitry.
Radiated and conducted out-of-band RF emissions are minimised with Analog Devices' advanced modulation techniques and closed-loop, sigma-delta architecture to enable a significant reduction in EMI.
The AD199x amplifiers, including the AD1990, AD1992, AD1994 and AD1996, are single-chip devices containing an integrated stereo modulator and stereo 'bridge-tied' load (BTL) power stage.
Power levels range from stereo 5W (mono 10W) to stereo 40W (mono 80W).
The AD1994 can be configured in a modulator-only mode.
This, coupled with external high power FETs enables very high power amplification, limited only by the power stage design.
The parts also incorporate critical peripheral functions, including pop/click suppression circuitry as well as short-circuit, overload and temperature protection.
The AD199x amplifiers can be combined with other Analog Devices audio products, including ADCs, DACs and codecs, as well as its SigmaDSP and SHARC audio processors.
The AD199x Class-D amplifiers are now sampling, with full production quantities available beginning in April 2005.
? Analog Devices: contact details and other news
? Email this article to a colleague
? Register for the free Electronicstalk email newsletter
? Electronicstalk Home Page
Related Business News
Taiwan stocks end down in biggest...
...drop in over 1 yr. Taipei, July 27 (Reuters) - Taiwan shares fell 4.22 percent on Friday to their lowest close in three weeks, marking their largest one-day percentage drop in more than a year, after a sell-off on Wall Street hurt big exporters such as TSMC .
Nippon Oil Aug refining seen flat, eyes Sudan crude
Tokyo, July 27 (Reuters) - Japan's top oil refiner Nippon Oil Corp. will keep its August processing volumes steady versus a year ago to meet summer gasoline demand and is seeking more Nile Blend crude to meet higher utility use.
Fluor Gains Eastman Chemical Gasification Plant Feed Work
Fluor Corporation announced today that it was selected by Eastman Chemical Company to provide front-end engineering and design work for a $1.6 billion gasification project along the Texas Gulf Coast.
Migao Corporation Secures Preferential Natural Gas Prices
Toronto, Ontario-- - Migao Corporation , a leading producer of specialty potash fertilizers for the Chinese market, is pleased to announce that it has negotiated preferential natural gas prices in Sichuan Province from China Petroleum & Chemical Corpora
South Korean envoy to meet Afghan...
...president over hostage crisis. A Seoul presidential envoy heading to Afghanistan will seek an urgent meeting with President Hamid Karzai to try to save 22 South Koreans kidnapped by the Taliban, officials said.