TFA9897UK中文资料Boosted audio system with adaptive sound maximizer and speaker protection数据手册恩XP规格书

描述 Description

Overview
The TFA9897 is a high efficiency class-D audio amplifier with a sophisticated
speaker-boost protection algorithm. It can deliver 1.2 W (RMS; THD = 1 %) output power
into an 8 Ω speaker at a battery voltage of 3.6 V. The internal boost converter raises the
supply voltage to 5.3 V, providing ample headroom for major improvements in sound
quality.

A safe working environment is provided for the speaker under all operating conditions.
The TFA9897 maximizes acoustic output while ensuring 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 audio signal is
always of optimum quality.

The adaptive sound maximizer algorithm uses feedback to accurately calculate both the
temperature and the excursion, allowing the TFA9897 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. This
feature maximizes the output power of the class-D audio amplifier while limiting quiescent
power consumption.

The TFA9897 also incorporates advanced battery protection. By limiting the supply
current when the battery voltage is low, it prevents the audio system drawing excessive
load currents from the battery (excessive load currents 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
rejection. The audio input interface is TDM and can be I²S configured. Control settings are
communicated via an I²C-bus interface.

The TFA9897 is available in a 30-bump WLCSP (Wafer Level Chip-Size Package) with a
400 μm pitch.

特性 Features

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

Environmentally aware - automatically adapts speaker parameters to acoustic and
thermal changes including compensation for speaker-box leakage

Output power: 1.2 W (RMS) into 8 Ω at 3.6 V supply voltage (THD = 1 %)

Low noise Receiver mode

Clip avoidance - DSP algorithm prevents clipping even with sagging supply voltage

Bandwidth extension option to increase low frequency response

Intelligent DC-to-DC converter maximizes audio headroom from any supply level and
limits current consumption at low battery voltages

Compatible with standard Acoustic Echo Cancellers (AECs)

High efficiency and low-power dissipation

Wide supply voltage range (fully operational from 2.5 V to 5.5 V)

TDM audio interface configurable from 2 slots (I²S) up to 16 slots

I²C-bus control interface (400 kHz)

Dedicated speech mode with speech activity detector

Speaker current and voltage monitoring (via the TDM-bus) for Acoustic Echo
Cancellation (AEC) at the host

Fully short-circuit proof across the load and to the supply lines

Sample frequencies from 8 kHz up to 48 kHz supported

Option to route TDM input direct to TDM output to allow a second TDM input slave
device to be used in combination with the TFA9897

Volume control

Low RF susceptibility

Input clock jitter insensitive interface

Thermally protected

Low ‘pop noise' at all mode transitions

应用 Application

Mobile phones


Tablets

Portable gaming devices

Portable Navigation Devices (PND)

Notebooks/Netbooks

MP3 players and portable media players