Nc is the Number of conduction cycles.
To measure conduction loss in a BJT/IGBT, using the following equation:
Where, V
CE
(sat) is the voltage in volt, which should be configure in application.
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Computation of Average Loss and Total Loss
Average and Total loss are calculated using the following equation:
Total Switching Loss=Ton Loss+Toff Loss+Conduction Loss
Concept to identify Ton and Toff using gate voltage for edge analysis:
Use gate voltage for edge analysis with default 50% edge level and hysteresis 10%.
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To find the start of Ton: The start of the Ton is 5% or 1.5 V whichever is lower on the rise slope of the gate voltage.
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To find the stop of Ton: The start index on the switch voltage is 5% or 1.5 V of the rise slope gate voltage. Move forward on
the switch voltage from the start index until 5% or the configured level is met.
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To find the start of Toff: The start index is 80% of the gate voltage. From the Stop index, search for 5% of the switch voltage
(on rise slope).
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To find the stop of Toff: The 80% of the gate voltage is start index. From this start index on switch current (fall slope) move
forward until 5% of the max (switch current) is met.
Measurement algorithms
470 MSO54, MSO56, MSO58, MSO58LP, MSO64 Help
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