User Manual

TPA005D02 Class D EVM Measured Characteristics
3-31
Details
Total harmonic distortion plus noise (THD+N) versus output power is shown
in Figure 3–23. A lower power levels (less than 40 mW), most of the distortion
is contributed by the class D amplifier device. Distortion at mid and high power
levels (40 mW to 1.9 W) is a function of the output filter components,
particularly the inductors.
A slight increase in supply voltage over 5 V substantially reduces the harmonic
distortion at power levels above 500 mW.
Figure 3–23. Distortion versus Output Power
10
0.1
0.01 0.05 0.1 0.2 0.5 1
THD+N – Total Harmonic Distortion Plus Noise – (%)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
2
5
2
0.5
0.2
1
0.02
V
DD
= 5 V
R
L
= 4Ω
P
o
– Output Power – W
0.05
0.03
20 KHz
1 KHz
100 Hz