The boosted, digital Class-D MAX98390 DSM smart amplifier, says the company, can safely drive higher power levels (up to 5.1W) into tiny speakers typically rated for much lower power between 1 to 3W.
“The MAX98390 smart amplifier was designed to boost audio quality in the smallest form factor to make it nimble enough to go into any device,” says Greg Mow, business manager for Mobile Audio Solutions at Maxim Integrated. “From providing the most balanced and loudest sound to offering the market’s highest efficiency and ease of design, the MAX98390 enables our customers to deliver a best-in-class, immersive sound experience.”
The MAX98390 uses integrated IV (current and voltage) sense and the company’s DSM algorithm to drive micro speakers to their maximum specified limits, while protecting against over excursion and over-temperature events. DSM’s thermal protection, says the company, enables designers to safely push their speakers well beyond their specified power rating to produce their maximum loudness, while DSM’s excursion protection lets designers drive speakers to their specified excursion limits, producing sound up to two octaves below the resonant frequency limit.
Design time is reduced, says the company, with the DSM Sound Studio GUI that allows users to quickly and easily characterize many speakers. Combined with DSM’s thermal protection, the result is maximum loudness across the significantly extended frequency ranges in minutes, with no complex programming required.
The MAX98390 offers peak efficiency at 86% – which is further improved with DSM’s Perceptual Power Reduction (PPR) feature that can yield up to an additional 25% efficiency – and a quiescent power consumption of ~24mW, suiting it for low-power devices that need longer battery life. On-chip DC resistance (Rdc) testing can be used on the production line for quality assurance to ensure a speaker is within impedance tolerance.
The MAX98390 is available now for $1.95. An evaluation kit – MAX98390EVSYS – is available for $200.