Class T amplifier
Encyclopedia
It is an implementation of Class D amplifier
Switching amplifier
A class-D amplifier or switching amplifier is an electronic amplifier where all power devices are operated as binary switches. They are either fully on or fully off. Ideally, zero time is spent transitioning between those two states....
s, but is claimed to improve the control scheme to create more efficient and higher quality audio amplification. One of the amplifiers, the TA2020, was named one of the twenty-five chips that 'shook the world" by the IEEE Spectrum
IEEE Spectrum
IEEE Spectrum is a magazine edited by the Institute of Electrical and Electronics Engineers. The IEEE's description of it is:IEEE Spectrum began publishing in January 1964 as a successor to Electrical Engineering...
magazine.
The control signals in Class T amplifiers may be computed using digital signal processing
Digital signal processing
Digital signal processing is concerned with the representation of discrete time signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing...
or fully analog techniques. Currently available implementations use a loop similar to a higher order Delta-Sigma
Delta-sigma modulation
Delta-sigma modulation is a method for encoding high-resolution or analog signals into lower-resolution digital signals. The conversion is done using error feedback, where the difference between the two signals is measured and used to improve the conversion...
(ΔΣ) (or sigma-delta) modulator, with an internal digital clock to control the sampled comparator. The two key aspects of this topology are that (1), feedback is taken directly from the switching node rather than the filtered output, and (2), the higher order loop provides much higher loop gain at high audio frequencies than would be possible in a conventional single pole amplifier.
Despite Tripath's claimed increased performance at a price similar to class D technology, financial difficulties caused Tripath to file for Chapter 11 bankruptcy protection on 8 February 2007.
Products and applications
Tripath used to sell the amplifiers as chipIntegrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...
s, or as chipset
Chipset
A chipset, PC chipset, or chip set refers to a group of integrated circuits, or chips, that are designed to work together. They are usually marketed as a single product.- Computers :...
s, to be integrated into products by other companies in several countries. For example:
- SonySony, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
, PanasonicPanasonicPanasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
and BlaupunktBlaupunktGmbH is a German manufacturer of electronics equipment, noted for its home and car audio equipment. It was a 100% subsidiary of Robert Bosch GmbH until March 1st, 2009 when its Aftermarket and Accessories branch including the brand name were sold to Aurelius AG of Germany for an undisclosed...
use them in several car stereos and integrated home cinemaHome cinemaHome cinema, also commonly called home theater, are home entertainment set-ups that seek to reproduce a movie theater experience and mood with the help of video and audio equipment in a private home....
systems - Apple ComputerApple ComputerApple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
used them in their Power Mac G4 CubePower Mac G4 CubeThe Power Mac G4 Cube was a small form factor Macintosh personal computer from Apple Inc. It was sold from 2000 to 2001. Its cube shape is reminiscent of the NeXTcube from NeXT, acquired by Apple in 1996. The machine was designed by Apple industrial designer Jonathan Ive...
, Power Mac G4Power Mac G4The Power Mac G4 was a series of personal computers that was designed, manufactured, and sold by Apple between 1999 and 2004. They used the PowerPC G4 series of microprocessors. They were heralded by Apple to be the first personal supercomputers, reaching speeds of 4 to 20 Gigaflops...
(Digital audio), eMacEMacThe eMac, short for education Mac, was a Macintosh desktop computer made by Apple Inc. It was originally aimed at the education market, but was later made available as a cheaper mass market alternative to Apple's second-generation LCD display iMac....
and iMac (Flat Panel)IMacThe iMac is a range of all-in-one Macintosh desktop computers built by Apple. It has been the primary part of Apple's consumer desktop offerings since its introduction in 1998, and has evolved through five distinct forms....
computers - Audio Research, an audio electronics company, formerly an exclusive tube circuit specialist, produced a Tripath based audiophile amplifier.
- Sonneteer a British hifi company,analogue amplifier and technology specialists, manufactured the Bronte amplifier (1999), based around a Tripath, Class T, module.
External links
- US Patent for ClassT amplifier
- Connexelectronic complete class T amplifier modules
- Audio Research amplifiers based on Tripath chips
- Winsome Labs offers kit and assembled Tripath amplifiers with higher power
- Sonneteer Bronte amplifier history based around early Tripath Module.