Texas Instruments SoundPlus INA1651EVM, Руководство пользователя, Страница: 10 / 20

Frequency (Hz)
Total Harm
onic Dist N
oise (%)
20 30 50 70 100 200 300 500 1000 2000 5000 10000 20000 50000 50000
0.0001
0.0002
0.0003
0.0005
0.0007
0.001
0.002
0.003
0.005 0.005
THD+N (%)
Frequency (Hz)
To
tal Har
mo
nic Distor
tion
+ N
oise (
%)
20 100 1000 10000 50000 50000
0.0001
0.001
0.005 0.005
Test Setup and Results
www.ti.com
10 SBOU212 – September 2018
Submit Documentation Feedback
Copyright © 2018, Texas Instruments Incorporated
INA1651EVM SoundPlus™ High Common-Mode Rejection Line Receiver
Evaluation Module
4.7 THD+N vs. Frequency
The THD+N vs. Frequency measurements were performed by sweeping the input signal from 20 Hz to
20 kHz with the measurement bandwidth of the Audio Precision APx555 set to 90 kHz. Figure 8 shows the
THD+N vs. Frequency measurement with an amplitude of 1 V
RMS
on the output of the INA1651. Note that
capacitor C8 on the output of the INA1651 can increase distortion at low frequencies due to non-linear
effects of the capacitor. Therefore, capacitor C8 is bypassed in these tests by a shunt installed across
jumper J5.
Figure 8. THD+N vs. Frequency Measurement with 1 V
RMS
Output
±15-V Supplies, 1-V
RMS
Output, 90-kHz MBW
Figure 9 shows the THD+N vs. Frequency measurement with an amplitude of 10 V
RMS
on the output of the
INA1651.
Figure 9. THD+N vs. Frequency Measurement With 10 V
RMS
Output
±15-V Supplies, 10-V
RMS
Output, 90-kHz MBW