AA4838
Agamem Microelectronics Inc.
PRELIMINARY
AUDIO POWER AMPLIFIER
• VOLUME CONTROL TABLE (Table 2)
Gain Voltage Range (% of Vdd)
Voltage Range (Vdd = 5) Voltage Range (Vdd = 3)
Low
High Recommended Low High Recommended Low High Recommended
0
77.5 100.00
75.0 78.5%
72.5 76.25%
70.0 73.75%
67.5 71.25%
65.0 68.75%
62.5 66.25%
60.0 63.75%
100.000% 3.875 5.000
5.000
3.844
3.719
3.594
3.469
3.344
3.219
3.094
2.969
2.844
2.719
2.594
2.469
2.344
2.219
2.094
1.969
1.844
1.719
1.594
1.469
1.344
1.219
1.094
0.969
0.844
0.719
0.594
0.469
0.344
0.000
2.325 3.000
2.250 2.363
2.175 2.288
2.100 2.213
2.025 2.138
1.950 2.063
1.875 1.988
1.800 1.913
1.725 1.838
1.650 1.763
1.575 1.688
1.500 1.613
1.425 1.538
1.350 1.463
1.275 1.388
1.200 1.313
1.125 1.238
1.050 1.163
0.975 1.088
0.900 1.013
0.825 0.937
0.750 0.862
0.675 0.787
0.600 0.712
0.525 0.637
0.450 0.562
0.375 0.487
0.300 0.412
0.225 0.337
0.150 0.262
0.000 0.187
3.000
2.306
2.231
2.156
2.081
2.006
1.931
1.856
1.781
1.706
1.631
1.556
1.481
1.406
1.331
1.256
1.181
1.106
1.031
0.956
0.881
0.806
0.731
0.656
0.581
0.506
0.431
0.356
0.281
0.206
0.000
-1
-2
-3
-4
-5
-6
-8
76.875%
74.375%
71.875%
69.375%
66.875%
64.375%
61.875%
59.375%
56.875%
54.375%
51.875%
49.375%
46.875%
44.375%
41.875%
39.375%
36.875%
34.375%
31.875%
29.375%
26.875%
24.375%
21.875%
19.375%
16.875%
14.375%
11.875%
9.375%
3.750 3.938
3.625 3.813
3.500 3.688
3.375 3.563
3.250 3.438
3.125 3.313
3.000 3.188
2.875 3.063
2.750 2.938
2.625 2.813
2.500 2.688
2.375 2.563
2.250 2.438
2.125 2.313
2.000 2.188
1.875 2.063
1.750 1.938
1.625 1.813
1.500 1.688
1.375 1.563
1.250 1.438
1.125 1.313
1.000 1.188
0.875 1.063
0.750 0.937
0.625 0.812
0.500 0.687
0.375 0.562
0.250 0.437
0.000 0.312
-10 57.5 61.25%
-12 55.0 58.75%
-14 52.5 56.25%
-16 50.0 53.75%
-18 47.5 51.25%
-20 45.0 48.75%
-22 42.5 46.25%
-24 40.0 43.75%
-26 37.5 41.25%
-28 35.0 38.75%
-30 32.5 36.25%
-32 30.0 33.75%
-34 27.5 31.25%
-36 25.0 28.75%
-39 22.5 26.25%
-42 20.0 23.75%
-45 17.5 21.25%
-47 15.0 18.75%
-51 12.5 16.25%
-56 10.0 13.75%
-61 7.5% 11.25%
-66 5.0% 8.75%
-78 0.0% 6.25%
6.875%
0.000%
• AUDIO POWER AMPLIFIER DESIGN
Audio Amplifier Design: Driving 1W into an 8ΩLoad
The following are the desired operational parameters:
Power Output: 1 WRMS, Load Impedance: 8Ω, Input Level:1 VRMS,
17
©Copyright Agamem Microelectronics Inc.
www.agamem.com.tw
2008/8/26
AGAMEM MICROELECTRONICS INCOPERATION RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE
TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. AGAMEM DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCTS OR CIRCUIT DESRIBED HEREIN; NEITHER
DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
AGAMEM [ AGAMEM MICROELECTRONIC INC. ]
