TFA9891UK/N1AZ NXP

TFA9891 9.5 V boosted audio system with adaptive sound maximizer and speaker protection Rev. 1 21 December 2016 Product short data sheet 1. General description The TFA9891 is a high efficiency class-D audio amplifier with a sophisticated speaker boost and protection algorithm. It can deliver 7.2 W peak output power to an 8 speaker, at a supply voltage of 3.6 V. The internal boost converter raises the supply voltage to 9.5 V, providing ample headroom for major improvements in sound quality. A safe working environment is provided for the speaker under all operating conditions. The TFA9891 maximizes acoustic output while ensuring that the diaphragm displacement and voice coil temperature do not exceed their rated limits. This function is based on a speaker box model that operates in all loudspeaker environments (e.g. free air, closed box or vented box). Furthermore, advanced signal processing ensures that the quality of the audio signal is never degraded by unwanted clipping or distortion in the amplifier or speaker. An integrated Dynamic Range Compressor (DRC) allows the speaker to operate at the highest possible power rating without suffering physical damage. Unlike competing solutions, the adaptive sound maximizer algorithm uses feedback to calculate both the temperature and the excursion. It allows the TFA9891 to adapt to changes in the acoustic environment. Internal intelligent DC-to-DC conversion boosts the supply rail to provide additional headroom and power output. The supply voltage is only raised when necessary. It maximizes the output power of the class-D audio amplifier while limiting quiescent power consumption. The TFA9891 also incorporates advanced battery protection. By limiting the supply current when the battery voltage is low, it prevents the audio system from drawing excessive load currents from the battery. Drawing excessive load currents from the battery could cause a system undervoltage. The advanced processor minimizes the impact of a falling battery voltage on the audio quality, by preventing distortion as the battery discharges. The device features low RF susceptibility because it has a digital input interface that is insensitive to clock jitter. The second order closed loop architecture used in a class-D audio amplifier provides excellent audio performance and high supply voltage ripple 2 rejection. The audio input interface is I S and the control settings are communicated via 2 an I C-bus interface. The device also provides the speaker with robust protection against ESD damage. In a typical application, no additional components are required to withstand a 15 kV discharge on the speaker. The TFA9891 is available in a 49-bump WLCSP (Wafer Level Chip-Size Package) with a 400 m pitch.TFA9891 NXP Semiconductors 9.5 V boosted audio system with adaptive sound maximizer and speaker protection 2. Features and benefits Sophisticated speaker-boost and protection algorithm that maximizes speaker performance while protecting the speaker: Fully embedded software, no additional license fee or porting required Total integrated solution that includes DSP, amplifier, DC-to-DC, sensing and more Adaptive excursion control which guarantees that the speaker membrane excursion never exceeds its rated limit Multiband Dynamic Range Compressor (DRC) allows independent control of up to three frequency bands Audio enhancement Real-time temperature protection - direct measurement ensures that voice coil temperature never exceeds its rated limit Environmentally aware - automatically adapts speaker parameters to acoustic and thermal changes including compensation for speaker box leakage Output power: 3.6 W (RMS) into 8 at 3.6 V supply voltage (THD = 1 %) Clip avoidance - DSP algorithm prevents clipping even with sagging supply voltage Bandwidth extension option to increase low frequency response Compatible with standard acoustic echo canceler (s) High efficiency and low-power dissipation Wide supply voltage range (fully operational from 2.7 V to 5.5 V) 2 Two I S inputs to support two audio sources or one Pulse Density Modulation (PDM) input 2 A third I S input dedicated to inter-chip communications 2 I C-bus control interface (400 kHz) 2 Speaker current and voltage monitoring (via the I S-bus or PDM output) for Acoustic Echo Cancellation (AEC) at the host Fully short-circuit proof across the load and to the supply lines 2 Sample frequencies from 8 kHz to 48 kHz supported in I S mode and 16 kHz to 48 kHz in PDM mode 2 3-bit clock/word select ratios supported (32x, 48x, and 64x) in I S mode Bit clock speed from 2.048 MHz up to 6.144 MHz in PDM mode 2 2 2 Option to route I S input directly to I S output allowing a second I S output slave device to be used in combination with TFA9891 TDM interface supported (with limited functionality) Volume control Low RF susceptibility Input clock jitter insensitive interface Thermally protected 15 kV system-level ESD protection without external components TFA9891 All information provided in this document is subject to legal disclaimers. NXP Semiconductors N.V. 2016. All rights reserved. Product short data sheet Rev. 1 21 December 2016 2 of 24