2*25W @4
Ω
TPA3123 Class-D Audio Amplifier Board
FIGURE 2-8 GAIN SETTINGS
TABLE 2-7 GAIN SETTINGS
Settings
Amplification Gain
K1
K2
Gain Level
Power Gain (dB) Typical
ON ON Weak
20
OFF ON
Low
26
ON OFF Medium
32
OFF OFF
High
36
Note:
1. High: Portable MP3/CD player with built-in volume control
Medium and low: General-purpose use
Weak: Preamplifier with fairly high output signal
2. Different gain levels correspond to different input sensitivities. Improper selection
will cause the audio distortion or even damage the amplifier board.
3. No preamplifier or other devices are needed for gain settings. We won’t assume
any responsibility for the damage caused by connecting extra devices.
2.8 DC Offset
Capacitive coupling output is applied to ensure no DC offset output.
2.9 LED Indicators
This amplifier has one power LED indicator which is marked as “Power (D2)”. The power
indicator will be illuminated in green when power-up. Please refer to the connection
schematics of the board for the LED location.
©
2004-2009 Sure Electronics Inc
AA-AB018_Ver1.0_Page 10
