When designing with an LM3150 and ambient temp > 30 Deg C, M2 defaults to a FDD8647L device. At 50 Deg C, M1 & M2 are restricted to the FDD8647L. I am then unable to substitute other devices. At 30 Deg C, I can select alternate devices. There are better devices than the FDD8647L (BSZ040N04LS G). WHy am I restricted to the FDD 8647L?
I will forward this to our Webench guy.
Frank D
Hello Rick,
Webench goes through all the possible FET combinations to check if the FET is feasible for the design requirements. If the power dissipation and junction temperature requirements are not met then it will reject that FET and move on to another. If there are no FETs found that are rated for the requirements, then the design is rejected quoting that no FETs in the database were found.
I believe that at 50C, not many FETs can make it. I would like to investigate further, so if could, please send us your design requirements in terms of the input voltage range and the load output voltage and current.
Regards,Akshay