Texas Instruments SLOU023A - Manual (Page 17)

The TPA112 MSOP Audio Power Amplifier Evaluation Module
3-3 Details
3.2 The TPA112 MSOP Audio Power Amplifier Evaluation Module
The TPA112 MSOP audio power amplifier evaluation module is powered by
a TPA112 150-mW stereo audio amplifier IC. It can drive either line-level
outputs, 32-
Ω
headphones, or 8-
Ω
speakers. A single-supply operational
amplifier (TLV2211) on the module provides a buffered midpoint voltage to
properly bias the noninverting inputs of the TPA112 amplifier IC.
The evaluation module can be used with the TI plug-n-play audio amplifier
evaluation platform (Figure 3 –1) or wired directly into circuits or equipment.
The module has single in-line header connector pins mounted to the under
side of the board. These pins allow the module to be plugged into the TI
platform, which automatically makes all the signal input and output, power, and
control connections to the module. The module connection pins are on
0.1-inch centers to allow easy use with standard perf board and plug
board-based prototyping systems. Or, the EVM can be wired directly into
existing circuits and equipment when used stand-alone.
The module appears in Figure 3–2 and its schematic is shown in Figure 3 – 3.
Figure 3–2. TPA112 MSOP EVM
GND
Vo2 IN2–
IN2+
Vdd GND
IN1+
U2
C7 R9
C1
C5
Vo1
GND
TEXAS
INSTRUMENTS
SLOP126
TPA112 MSOP EVM
C6
R10
R8
R7 C4
R1
R2
R3
R4
C2
R5
R6
C3
JP1
IN1–
+
† Due to the very small size of the MSOP IC package, the standard part number TPA112 is replaced with the code TIAAD
Figure 3–3. TPA112 MSOP EVM Schematic Diagram
IN 1–
Vo1 VDD
Vo2
GND
IN 2–
C3
1 µ F
R7
20 k Ω
C4
0.1 µ F
8
7
6
5
1
2
3
4
Vo2
Audio
Input 1
R10
82 k
Ω
TPA112
MSOP
C6
1
µ
F
+
VDD
2.5 to 5.5 V
GND
C5
10
µ
F
Vo1
R8
82 k
Ω
IN 1+
IN 2+
R9
20 k
Ω
C7
0.1 µ F
Audio
Input 2
R1
20 k Ω
C1
0.1 µ F
R4
20 k Ω
C2
0.1
µ
F
_
+
R6, 20 k Ω
R5
20 k Ω
VDD
Mid
Mid
R2
82 k Ω
R3
82 k
Ω
U1
U2
IN +
IN –
IN +
IN –