Texas Instruments SLOU025, Руководство пользователя

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The TPA122 MSOP Audio Power Amplifier Evaluation Module
3-4 Details
3.2.1 TPA122 Audio Amplifier IC
The TPA122 audio amplifier IC is a CMOS device intended primarily for
high-performance line-level output, headphone driver, and small speaker
applications. It is supplied in a very small surface-mount MSOP package and
has been designed to operate from low supply voltages (between
approximately 2.5 V and 5.5 V) and to deliver up to approximately 150 mW into
8-
Ω
speakers with low distortion. As a line-level driver, distortion levels
(THD+N) are below 0.07% into 10-k
Ω
loads across the audio band (20 Hz to
20 kHz). As a headphone driver, distortion levels are below 0.4% into 32-
Ω
loads across the audio band. And as a speaker driver, distortion levels are
below 0.8% into 8-
Ω
loads across the audio band. Typical applications include
portable computers, desktop computers, personal audio, toys, games, and
similar audio applications.
The IC includes two separate internal amplifiers, depop circuitry, and a
common shutdown control (Figure 3 – 4). The load for each channel is
connected between the V
O
pin and GND through a coupling capacitor. For
more information, see the TPA122 amplifier IC data sheet, TI Literature
Number SLOS211.
Figure 3–4. TPA122 Amplifier IC
Stereo
RL RL
CC
CC
VO1
VO2
Bypass
IN2
IN1
CB
RF
RF
RI
RI
CI
CI
R
L
Stereo Audio
Input
Bias
Control
From System
Control
CS
VDD
6
3
5
1
2
8
7
–
–
+
+
Shutdown
4