MERUS™ multilevel switching technology from Infineon Technologies

     When designing battery-powered portable audio devices for consumer speaker applications, the need to maximize battery life and provide excellent sound quality while achieving a compact exterior design and reducing system costs is critical. Infineon Technologies' MERUS™ multilevel switching technology, designed to reduce switching losses and achieve efficient audio amplification at both low and high output power, provides significant advantages for these applications. The new IC family uses second generation MERUS™ multilevel switching amplifier technology and a compact 40-pin QFN package for battery powered speakers, Bluetooth/wireless/smart speakers and bar speakers, conference speakers, multi-channel/multi-room audio systems and other applications.

     The new IC series includes MA2304DNS and MA2304PNS. Among them, the MA2304DNS integrates a fully configurable digital signal processor (DSP) and the MA2304PNS has a built-in audio controller with volume control. Both devices use a second generation multilevel switched Class D audio amplifier that operates inductively free and provides a 2 x 37 W bridged load (BTL) output rating. Its power supply voltage range (PVDD) is 10 to 20 V, providing high fidelity sound quality. With five-stage voltage modulation, the idle power consumption is as low as 52 mW, so there is no need for complex dynamic track tracking system. With only one-fifth of the vacant power consumption of traditional Class D audio amplifiers, these devices are ideal for battery-powered speaker applications, extending battery life and reducing the cost of the battery unit.

     The new IC series can achieve efficiency of more than 80% at low power output, which enables longer battery life and improved thermal management capabilities for multi-channel products. The multilevel switch design relaxes the requirements for electromagnetic compatibility (EMC) and enables non-inductive applications in the full power range at a lower cost. Compared to traditional two - and three-stage Class D audio amplifiers, the new IC family speeds product time to market by reducing electromagnetic interference (EMI) without compromising audio effects and system efficiency. This lower and adjustable EMI enables industrial designs that would otherwise require heat sinks or traditional LC filters in power-powered multi-channel applications.

     The high order internal feedback loop ensures excellent audio with low total harmonic distortion (THD) and background noise. Non-inductance applications help achieve minimum output filtering, avoiding the cumbersome problem of large inductors, and thus reducing system costs without limiting output power. The highly configurable DSP integrated in the MA2304DNS can tune the audio for perfect sound quality, and adjust the actual speaker application with equalization, restriction, and similar features. The MA2304PNS provides simpler volume control functions and audio controllers for systems that process audio using or connected to an application processor.