Facebook
Google
GitHub
Linkedin
This is one of the first times I have looked at a datasheet, and I would like to get an estimate of the power dissipated during gate driver switching.
I've assumed some random data (hopefully realistic) and, if I'm not wrong, in line with the absolute max ratings of the driver in question. I also realize that for example Qg in the datasheet is specified for Vds=40V, while I assumed 50V, so "it would not fit." I used a general formula that should included all losses:
Are the calculations correct? Am I doing something wrong?
Do I choose the current to turn the driver off (I_drv,on and I_drv,off)? Or is it defined in the datasheet of the gate driver? ..because I assumed 5A, but I read online that the formula Ig=2*f*Qg=3.2mA should be used .. but this seems strange to me because it would disproportionately increase losses! There is something I don't understand..
I repeat that the data are made up, so (given my inexperience) they might be unrealistic and strange!
I am interested if the gate driver parameters taken from the datasheet (Qg and Coss) are correct and if I have forgotten/made mistake something.
Thanks!
(P.S.: in the datasheet there is the section "8.2.2.4 Power Dissipation" that shows the formula for calculating P_diss (as I did in the photo), but it seems to me to be lacking some terms ... or maybe it is neglected. I would like to compare the dissipation losses of multiple gate drivers with each other, so I would like to use one general formula including all the terms without having to check the single P_diss in each datasheet)
I've assumed some random data (hopefully realistic) and, if I'm not wrong, in line with the absolute max ratings of the driver in question. I also realize that for example Qg in the datasheet is specified for Vds=40V, while I assumed 50V, so "it would not fit." I used a general formula that should included all losses:
Are the calculations correct? Am I doing something wrong?
Do I choose the current to turn the driver off (I_drv,on and I_drv,off)? Or is it defined in the datasheet of the gate driver? ..because I assumed 5A, but I read online that the formula Ig=2*f*Qg=3.2mA should be used .. but this seems strange to me because it would disproportionately increase losses! There is something I don't understand..
I repeat that the data are made up, so (given my inexperience) they might be unrealistic and strange!
I am interested if the gate driver parameters taken from the datasheet (Qg and Coss) are correct and if I have forgotten/made mistake something.
Thanks!
(P.S.: in the datasheet there is the section "8.2.2.4 Power Dissipation" that shows the formula for calculating P_diss (as I did in the photo), but it seems to me to be lacking some terms ... or maybe it is neglected. I would like to compare the dissipation losses of multiple gate drivers with each other, so I would like to use one general formula including all the terms without having to check the single P_diss in each datasheet)
