World’s most efficient high power audio chip enables battery-powered amplified speakers to run 3 hours per day for 10 months on a set of 1.5V batteries
Bristol, UK, 5th Oct: Audium Semiconductor has launched an audio power amplifier IC which, at normal listening levels[1], is 20 times more efficient than competing devices, such as Class D[2] amplifiers, without compromising audio quality. The AS1001 operates from a nominal 1.5V power supply and delivers 100W peak power output. The amplifier is so efficient that battery-powered amplified loudspeakers can run for up to 10 months on a set of four ‘C’ batteries, playing for three hours per day, vastly reducing CO2 from power generation and pollution from battery production[3].
The amplifier also enables the development of smaller, cooler, mains-powered audio equipment, with fewer heat sinks. Applications include totally wireless speakers, home theatre surround sound speakers and battery-powered travel speakers. Future Audium ICs will support MP3 docking stations and USB powered speakers.
The AS1001 architecture uses patented techniques to minimise both fixed power losses and output-dependant variable power losses. The modulation scheme uses low switching rates to minimise switching losses. Power rail switching means that the amplifier operates efficiently from a low voltage rail most of the time, with a DC-DC boost converter driving higher voltage transistors on extreme audio peaks.
“Traditionally, audio amplifiers have only reached quoted efficiency figures at maximum output, which is like building a city-car that’s only efficient at 200mph and anything but efficient at 30,” said Huw Davies, CCO at Audium. “The AS1001 marks a huge leap forward in efficiency and has come from examining how equipment is really used rather than striving for a marketable arbitrary figure.”
“Over 700 million consumer audio devices are sold each year, so the real world efficiency of these has a huge impact on the amount of energy we consume,” commented Malcolm Penn, CEO Future Horizon’s analyst house. “Looking beyond the environmental implications, the technology behind the AS1001 will enable a whole new class of low power consumer products.”
Targeting battery powered applications; the AS1001 is a single 64QFN package and operates directly from a 0.8V – 1.8V supply (compatible with, for example, alkaline primary cells and Ni-MH secondary cells). Samples are available now, priced from $8 each in 1000+ quantities.
