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Figure 3–23. distortion versus output power – Texas Instruments TPA005D02 User Manual

Page 45

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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 – T

otal Harmonic Distortion Plus Noise – (%)

TOTAL HARMONIC DISTORTION PLUS NOISE

vs

OUTPUT POWER

2

5

2

0.5

0.2

1

0.02

VDD = 5 V

RL = 4

Po – Output Power – W

0.05

0.03

20 KHz

1 KHz

100 Hz