Power Amplifier
High quality mono output is provided. The DAC output is connected through a buffer
stage to the input of the Audio Power Amplifier, using two coupling capacitors The
mono buffer stage also includes a mixer of the LINEL and LINER inputs as well as a dif-
ferential monaural auxiliary input (line level) which can be, for example, the output of a
voice CODEC output driver in mobile phones.
In the full power mode, the Power Amplifier is capable of driving an 8Ω Loudspeaker at
maximum power of 440mW, making it suitable as a handsfree speaker driver in Wire-
less Handset Application.
The Low Power Mode is designed to be switched from the handsfree mode to the nor-
mal earphone/speaker mode of a telephone handset.
The audio power amplifier is not internally protected against short-circuit. The user
should avoid any short-circuit on the load.
PA Features
• 0.44W on 8Ω Load
• Low Power Mode for Earphone
• Programmable Gain (-22 to +20 dB)
• Fully Differential Structure, Input and Output
Table 115. PA Gain
APAGAIN 3:0
0000
0001
0010
0011
Gain (db)
-22
20
17
14
11
8
0100
0101
0110
5
0111
2
1000
1001
1010
1011
-1
-4
-7
-10
-13
-16
-19
-22
1100
1101
1110
1111
98
AT8xC51SND2C
4341D–MP3–04/05
ATMEL [ ATMEL ]
