Audio chipset drives efficiency up and scales from 50 to 500 W

Audio chipset drives efficiency up and scales from 50 to 500 W

Until recently, there has been a perception that Class D is inferior to Class AB in terms of audio performance. That’s changing with the introduction of a Class D audio amp driver chipset.

The IRS2092 Audio IC, and its companion digital audio MOSFETs, form a Class D chipset solution comparable to Class AB in performance yet much smaller. In a 100-W application, for example, the IRS2092 IC and IRF6645 DirectFET MOSFETs reduce board size by 60% and eliminate 20% of the parts from the typical bill of materials. A reference design (IRAUDAMP5) based on the IRS2092 and IRF6645 demonstrates 96% efficiency at 120 W in the MOSFET stage, and a THD+N of 0.005% at 60 W, 4 Ω. From an energy-efficiency perspective, the overall energy efficiency of Class AB is about 30% typically. The chipset can address output power from 50 to 500 W by simply replacing the MOSFETs paired with the IRS2092 IC.

The IRS2092 incorporates four essential functions that, in addition to reducing board space, eliminates much of the learning curve for audio designers looking to implement a Class D solution. In contrast to linear amplifiers such as Class AB the MOSFETs cannot be turned on gradually. Therefore a well-designed output stage with finely tuned, well-protected PWM switching is critical to the overall design. The IRS2092 integrates PWM modulator, internal level-shifting, MOSFET gate driver, and overload protection.

International Rectifier , El Segundo , CA
Graham Robertson 310-726-8512

http://www.irf.com