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I found this formula to calculate \$E_{\text{on}}\$ for an IGBT:

$$E_{\text{on}} = \int\limits_{t_1}^{t_2}p_v(t)\text{ d}t = \int\limits_{t_1}^{t_2}v_{CE}(t) \times i_C(t)\text{ d}t$$

How can I calculate \$E_{\text{on}}\$ from datasheet parameters? I'm confused how to determine/calculate \$t_1\$ and \$t_2\$.

I have a new question here, are these t1 and t2 equal to ton(tdn+tr)?

Here is the data sheet: Semikron Datasheet IGBT

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    \$\begingroup\$ Eon is usually a datasheet parameter, no calculation needed. \$\endgroup\$
    – Hearth
    Commented Nov 3, 2021 at 15:43
  • \$\begingroup\$ Hearth is right. Eon is already given in the datasheet. \$\endgroup\$
    – Rohat Kılıç
    Commented Nov 3, 2021 at 15:47
  • \$\begingroup\$ The Eon can be ratiometrically scaled for your working voltage/current against their test voltage/current (quite linear). HOWEVER... the turn-on speed can't... be mindful of your gateresistor vs the testcase gate resistor (99% of the time the stated value is good enough anyway) \$\endgroup\$
    – user16222
    Commented Nov 3, 2021 at 15:51
  • \$\begingroup\$ Yes, Eon is there. I actually want to use the formula to check if i get the same Eon with the one from datasheet, but i'm stuck with t1,t2. Anyway, thanks for the answers \$\endgroup\$
    – Laz
    Commented Nov 3, 2021 at 15:53
  • \$\begingroup\$ @Laz It's not really possible to calculate from other parameters, it has to be measured. This is because Vce and Ic will be varying throughout the switching transient. Your formula also ignores the contribution from gate charging current (which is normally significantly smaller, so ignoring it is well-founded, but if you want to be as precise as possible you'd need to include it). \$\endgroup\$
    – Hearth
    Commented Nov 9, 2021 at 13:50

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You can't calculate it from other datasheet parameters; that's why it's given in the datasheet as its own parameter. The formula you've shown is correct, but you can't just use the saturation voltage and operating current for Vce and Ic in the formula; both Vce and Ic change during the switching transient, not necessarily linearly and at a rate determined by your gate drive strength. It's a parameter that has to be measured, not calculated. Even still, it depends on the load as well; if your load is resistive and the switching energy is measured with an inductive load, you'll see different results than the datasheet numbers.

The formula also overlooks the contribution from gate charging current, but this is a small contribution and can usually be ignored. That energy is still there, though.

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