4.Connect a scope probe from channel 1 between the on/off control pin and reference ground (SGND) on the Evaluation Board.
5.Set channel 2 on the oscilloscope to be DC coupled and to the appropriate range for the output voltage.
6.Connect a coaxial cable from channel 2 to BNC2 on the Evaluation Board.
7.Set the Time base to 2mS/Div
8.Set the Trigger for a
9.Enable the on/off switch to turn on and use the cursor V Bars for measurement of the delay time, and then record the waveform on the oscilloscope.
8.4.Thermal Characteristic
8.4.1 Efficiency
Efficiency is the ratio of total output power to the input power. It is typically measured at full load and nominal input voltage.
Test
1)Turn on the fan.
2)Set the enable switch SW2 to the converter ON.
3)Adjust the input voltage to the desired operating point.
4)Set the electronic or resistive Load to the desired operating point.
5)Read and note the output voltage (DVM3) and input voltage (DVM2).
6)Read and note the input and output currents from the DVM1 and the electronic load.
7)Use the following formulas to calculate the efficiency:
Efficiency= (Pout/Pin) × 100(%)
Pin = Iin × Vin
Pout = Iout × Vout
The following graph shows the efficiency curves of the DNM04S0A0S10P A module when measuring at different operating points.
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% | 95 |
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EFFICIENCY | 90 |
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| VI = 5.5V |
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| VI = 5.0V |
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85 |
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| VI = 4.5V |
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| 80 |
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| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
LOAD (A)
18
