TFA9887 Datasheet, PDF (1/20 Pages) NXP Semiconductors – Audio system with adaptive sound maximizer and speaker protection

TFA9887
Audio system with adaptive sound maximizer and speaker
protection
Rev. 1 — 11 July 2012
Product short data sheet
1. General description
The TFA9887 is an audio system consisting of a high efficiency class-D audio amplifier,
and embedded DSP with a sophisticated speaker-boost and protection algorithm and an
intelligent DC-to-DC converter. It can safely deliver 2.65 W (RMS; THD = 1 %) output
power into a 4  speaker that is nominally only rated for 0.5 W. The integrated intelligent
DC-to-DC converter allows the system to deliver this power from a battery voltage of
3.6 V. The audio input interface is I²S and the control settings are communicated via an
I²C-bus interface.
The TFA9887 guarantees safe speaker operation under all operating conditions. It
maximizes acoustic output while ensuring diaphragm displacement and voice coil
temperature do not exceed rated limits. The processing is capable of providing a
significant improvement in sound volume and quality, while also ensuring reliable
operation. This function is based on and adaptive model that operates in all loudspeaker
environments (e.g. free air, closed box or vented box). Furthermore, advanced signal
processing ensures the quality of the audio signal is always optimized.
Adaptive DC-to-DC conversion boosts the supply voltage only when necessary (when the
output signal level is high). This maximizes the output power of the class-D audio amplifier
while limiting quiescent power consumption. The TFA9887 also adapts the amplifier gain
to limit battery current when the battery voltage is low.
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
rejection.
The TFA9887 is available in a 29-bump WLCSP (Wafer Level Chip-Size Package) with a
400 m pitch.
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 - guarantees that the speaker membrane excursion never
exceeds its rated limit
 Real-time temperature protection - direct measurement ensures that voice coil
temperature never exceeds its rated limit