Texas Instruments APA100 - Manual (Page 36)

Total Harmonic Distortion + Noise
5-2
5.1 Total Harmonic Distortion + Noise
The APA100 has excellent total harmonic distortion + noise (THD+N).
Figure
5−1 and Figure 5−2 show the THD+N versus frequency, and
Figure 5−3 and Figure 5−4 show THD+N vs output power. A 30-kHz
bandwidth limit was used on the audio precision to limit switching frequency
from affecting the measurement.
Figure 5−1. APA100 THD+N vs Frequency With 4-
W
Load
100
10
1
0.1
0.01
20 100 200 1 k 2 k 20 k
P
O
= 1 W
P
O
= 10 W
P
O
= 40 W
P
O
= 70 W
V
CC
= 29.5 V
THD+N − T
otal Harmonic Distortion + Noise − %
f − Frequency − Hz
Figure 5−2. APA100 THD+N vs Frequency With 8-
W
Load
100
10
1
0.1
0.01
20 100 200 1 k 2 k 20 k
P
O
= 1 W
P
O
= 10 W
P
O
= 40 W
P
O
= 20 W
V
CC
= 29.5 V
THD+N − T
otal Harmonic Distortion + Noise − %
f − Frequency − Hz