Tool/software:
Hello,
I try to find some information about the calculation of power dissipation of the IC for different operation conditions. I tried the preliminarry Excel calculation tool and there for my operation conditions I will get a value of more than 3W for IC dissipation and a dT of 130°C.
I entered the following values: Input voltage 48V, Output voltage 63V, LED-current 4A
switching frequency would be 400kHz.
There are no information on power looses inside the IC - so DC looses can be calculated regarding 150mOhm Mosfets, and voltage regulator is mentioned with 10mA current. For switching looses there are no informations, but in any case I will not come to more than 3W.
2. question:
To reduce the power dissipation I could supply the IC only with 12V for controlling - the LED power path needs to rund with 48V. This means, that Vin would be 12V, while SW-pin will come to 48V. Also the measureing pins for current will have a common mode of 48V.
Is this a problem and are there any points I have to take care on.
Many thanks
Juergen
