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I'm trying to calculate the switching loss of the MOSFET which is used for a DC-DC Boost converter. Input Voltage : 9V-16V

Output Voltage : 30V

Output Current : 0.3A.

Switching Freq : 455kHz

Based on this [App Note][1] the Switching loss formula is given on page 3, equation 4.

enter image description here

If I calculate the switching loss based on the above formula, it comes to around 14W.

In this Article, the formula for calculating the switching loss is different.

enter image description here

Which one is the correct formula and could you explain the reason for 2 different formulas?

[1]: https://www.ti.com/lit/an/slyt664/slyt664.pdf?ts=1617773788537&ref_url=https%253A%252F%252Fwww.google.com%252F#:~:text=MOSFET%20switching%20losses%20are%20a,as%20shown%20by%20Equation%204.&text=where%20VIN%20%3D%20VDS%20(drain%2D,IG%20is%20the%20gate%20current

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    \$\begingroup\$ these formulas may well be identical because each of GS2 and GD capacitances is charged by a current \$I_G/2\$ \$\endgroup\$ – V.V.T Apr 7 at 12:15
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    \$\begingroup\$ Switching frequency 455 kHz ... that'll make you popular! \$\endgroup\$ – user_1818839 Apr 7 at 12:27
  • \$\begingroup\$ I'm unable to understand. And why 455kHz would make me popular/ \$\endgroup\$ – Newbie Apr 7 at 13:04
  • \$\begingroup\$ That’s the IF channel for AM radios , some interference is possible nearby. \$\endgroup\$ – Tony Stewart EE75 Apr 7 at 13:49
  • \$\begingroup\$ Also Q=CV and Ig =Vgs/Rg peak during tR,tF so peak power is something like Vg^2/Rg * C * 2f (?) for C=Ciss which is related to Cgd,Cgs or Qgd,Qgs \$\endgroup\$ – Tony Stewart EE75 Apr 7 at 13:55

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