Infineon Technologies has launched a family of highly monolithic Class D audio amplifier solutions which promise to provide high levels of audio performance while cutting typical power consumption by 75% compared to that of conventional Class D amplifiers.
The new MA12040/P and the MA12070/P amplifiers are part of the MERUS™ portfolio of audio products, uniting the existing Infineon portfolio of multi-chip modules and discrete audio products under one umbrella.
The building block for the high performance of the MERUS Class D amplifiers is a new technology: multi-level switching. The MA120x0 amplifiers set new benchmarks in parameters such as power consumption, solution size, audio performance, EMI and Bill-of-Materials (BoM) cost.
The new devices make up to five levels of output signal modulation possible. In contrast to traditional audio amplifiers, the Infineon multi-level amplifiers use additional on-chip MOSFETs and capacitors to produce outputs with a higher signal granularity, supporting higher switching frequencies and scalable output-signal levels. This results in a small form factor and almost no switching loss measurable in idle mode.
The MA12040/P and MA12070/P offer power consumption of around 250mW. This makes them well suited to portable battery-powered products, and to applications with challenging thermal management constraints.
A comparison with traditional Class D amplifiers is instructive: conventional amplifiers are only efficient at the highest volume levels, at which Total Harmonic Distortion (THD) is high. In practice, then, listeners today typically drive Class D-based systems at lower sound levels, at which they perform at low efficiency.
In these realistic audio playback situations, conventional devices’ 1W average power consumption is four times higher than that of the MERUS integrated multi-level audio amplifier ICs.
The newly introduced Infineon devices support up to four channels, which can be configured in parallel bridge-tied-load (PBTL), in bridge-tied-load (BTL) or in single-ended (SE) mode. A single IC can provide up to 160W peak output (16A maximum) in a single PBTL channel. It can also be set up as a 2.1 system with 2 x 20W tweeters as SE channels and 1 x 40W woofer speaker as a BTL channel.
In addition, the products feature an advanced digital power management scheme, low THD+Noise of 0.003%, and low emitted EMI.
Infineon’s multi-level technology allows for operation without filters and without a heat-sink. This reduces the BoM and overall system costs, due to a reduced component count and lower cooling requirements.
FTM Development Boards
These reference boards are size-optimized implementation examples for the highly power-efficient MERUS™ analog (MA120x0), or digital (MA120x0P), input multilevel Class D amplifier ICs. The ICs are specifically targeted for high-performance, filter-less and heat-sink-free audio applications.