Class-H audio amp promises richer sound from smaller devices

November 12, 2015 // By Graham Prophet
A smart amplifier enables TI says, deeper, richer and louder audio for next-generation smartphones. The amp, with integrated speaker protection, is supported by a new software suite to accelerate development.

The low-power smart amplifier aims to allow designers to develop next-generation smartphones with leading audio quality at peak volumes while maximising battery efficiency. The TAS2555 Class-H audio amplifier with integrated speaker protection uses back electromotive force and low power of 5.7W to produce bigger sound from small devices. TI says it is the first to provide both integrated and nonintegrated smart amplifiers, giving engineers a broad range of design options.

The TAS2555 is also the first low-power amplifier supported by the PurePath Console 3 software suite, for both advanced and beginner designers, to meet diverse system requirements. The solution takes the guesswork out of speaker characterisation and includes tools for tuning and integration into end products, accelerating time to market for smartphones, tablets and other audio-enabled portable electronics.

The TAS2555 offers; louder and clearer audio with 5.7W output power into 4Ω and 3.8W into 8Ω at 4.2V; low idle-channel noise (ICN) simplifies designs: 15.9-µV ICN eliminates audible speaker noise when using the smartphone in a receiver or pause mode and also eliminates the need for external components.

Integrated multilevel Class-H boost converter and automatic gain control dynamically adjusts audio output during periods of low battery voltage to maximises battery life. User-specified boost control helps customise boost on/off based on end-equipment power profile requirements.

Any processor with an I ²S output can be employed to enable on-chip speaker protection. This greatly reduces porting and integration time, enabling end equipment manufacturers to get to market faster.

Along with the PurePath Console 3 software suite, TI offers an evaluation module (EVM) and a learning board tool for speaker evaluation. The TAS2555YZEVM is available for $149.

The TAS2555 in a 3.4 7 x3.23-mm, 42-ball wafer-level chip-scale package (WCSP) and is priced at $2.50 (1,000).

Texas Instruments;