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IRAUDAMP18 REV
1.0
Test Procedures
Test Setup:
1. Connect
4
, 100W load to both output connectors, P1 and P2 and audio analyzer (Ap).
2. Connect Audio Signal Generator to CN1 for CH1 and CH2 respectively (Ap).
3. Connect a single power supply to P3 pre-adjusted to 18-31V as shown on Figure above
4. Turn on the power supply.
5. Turn on SW1(right side).
6. Blue LED (Normal) stays turning on after RED LED extinguished.
7. With an Oscilloscope, monitor switching waveform at VS of CH1 and CH2.
8. Quiescent current for the power supply should be 70mA
10mA at 31V.
Functionality Audio Tests:
9. Sweep the audio signal voltage from 15 mV
RMS
to 1.5 V
RMS
.
10. Monitor the output signals at P1/P2 with an oscilloscope. The waveform must be a non
distorted sinusoidal signal with input sinusoidal signal below 1Vrms.
Performance and Test Graphs
Power vs THD+N
Test Conditions:
VBus = 31V
Input Signal=1 kHz
Load Impedance = 4 ohms
Color
Sweep
Trace
Line Style
Thick
Data
Axis
Comment
1
1
Red
Solid
2
Anlr.THD+N Ratio
Left
Ch1 4ohms 31V
1
3
Blue
Solid
2
Anlr.THD+N Ratio
Left
Ch2 4ohms 31V
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
20m
40
50m
100m
200m
500m
1
2
5
10
20
W
THD+N vs Power
Fig 2
