
SLUU195 − June 2004
6 Test Results and Performance Data
6.1Efficiency and Power Loss
Figure 8 shows the efficiency as the load varies from 10 A to over 100 A. The efficiency at full load is about 84.3%.
Figure 7 shows the total loss versus the load current, which is approximately 28.3W at 100 A.
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  | OVERALL EFFICIENCY | 
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  | 90  | 
  | OUTPUT CURRENT | 
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  | 40  | ||
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  | VIN = 12 V  | 
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  | fSW = 420 kHz  | 
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  | 35  | |
  | 85  | 
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  | W  | 30  | 
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Efficiency − %  | 80  | 
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  | − Power Loss −  | 25  | 
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  | 20  | ||
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Percent  | 75  | 
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  | LOSS  | 15  | 
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  | 10  | 
  | 70  | 
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  | 65  | 
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  | 0  | 20  | 40  | 60  | 80  | 100  | 120  | 
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  | IOUT − Output Current − A  | 
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TOTAL POWER LOSS
vs
OUTPUT CURRENT
  | VIN = 12 V  | 
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  | fSW = 420 kHz  | 
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0  | 20  | 40  | 60  | 80  | 100 | 120 | 
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  | IOUT − Output Current − A  | 
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Figure 8.  | Figure 9.  | 
TPS40090   | 15  |