D
debugginglife
- Jan 1, 1970
- 0
i have been trying to use tl494 to obtain 15V 2Amp power supply, my
switching frequency is about 20kHz and input voltage is 24-35V. However
when i connect the load to the line my mosfet [irfz34n Ron=0.04 ohm ]
gets hot too fast and it dissipates about 6W. I calculated the
switching and conduction losses and it shouldnt dissipate such amout of
energy. [ When i use the mosfet without tl494 there is no such
problem.]
What can be the possible causes of the problem ? [ i suspect from
switching losses but i cant figure out where i have done the mistake]
* i read the ti's application note and all the calculations are based
on the note [slva001d].. in the note darlington pair is used and i also
tired with single npn transistor with proper connections but the result
is the same
switching frequency is about 20kHz and input voltage is 24-35V. However
when i connect the load to the line my mosfet [irfz34n Ron=0.04 ohm ]
gets hot too fast and it dissipates about 6W. I calculated the
switching and conduction losses and it shouldnt dissipate such amout of
energy. [ When i use the mosfet without tl494 there is no such
problem.]
What can be the possible causes of the problem ? [ i suspect from
switching losses but i cant figure out where i have done the mistake]
* i read the ti's application note and all the calculations are based
on the note [slva001d].. in the note darlington pair is used and i also
tired with single npn transistor with proper connections but the result
is the same