TFA9881_15 Datasheet, PDF (1/32 Pages) NXP Semiconductors – 3.4 W PDM input class-D audio amplifier

TFA9881
3.4 W PDM input class-D audio amplifier
Rev. 3 — 23 April 2013
Product data sheet
1. General description
The TFA9881 is a mono, filter-free class-D audio amplifier in a 9-bump WLCSP (Wafer
Level Chip-Size Package) with a 400 m pitch.
The digital input interface is an over-sampled Pulse Density Modulated (PDM) bit stream.
The TFA9881 receives audio and control settings via this interface. Dedicated silence
patterns are used to configure the control settings of the device, such as mute, gain, Pulse
Width Modulated (PWM) output slope, clip control and bandwidth extension (this control
mechanism is not required if the default settings are used). The Power-down to Operating
mode transition is triggered when a clock signal is detected.
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 the TFA9881
provides excellent audio performance and high supply voltage ripple rejection.
2. Features and benefits
 Small outline WLCSP9 package: 1.3  1.3  0.6 mm
 Wide supply voltage range (fully operational from 2.5 V to 5.5 V)
 High efficiency (90 %, 4 /20 H load) and low power dissipation
 Quiescent power:
 6.5 mW (V_DDD = 1.8 V, V_DDP = 3.6 V, 4 /20 H load, f_clk = 2.048 MHz)
 7.8 mW (V_DDD = 1.8 V, V_DDP = 3.6 V, 4 /20 H load, f_clk = 6.144 MHz)
 Output power:
 1.4 W into 4  at 3.6 V supply (THD = 1 %)
 2.7 W into 4  at 5.0 V supply (THD = 1 %)
 3.4 W into 4  at 5.0 V supply (THD = 10 %)
 Output noise voltage: 24 V (A-weighted)
 Signal-to-noise ratio: 103 dB (V_DDP = 5 V, A-weighted)
 Fully short-circuit proof across load and to supply lines
 Current limiting to avoid audio holes
 Thermally protected
 Undervoltage and overvoltage protection
 High-pass filter for DC blocking
 Invalid data protection
 Simple two-wire interface for audio and control settings
 Left/right selection
 Three gain settings:3 dB, 0 dB and +3 dB
 PWM output slope setting for EMI reduction