Help! An engineer has to design an AC-DC converter in the figure below with respect to its thermal management. The converter uses MOSFETs for the switching purposes and its characteristics are given in appendix (1). The thermal management designs consideration for the converter are as follows:
a) All MOSFETs are placed on the same heat sink, with the sink-ambient thermal resistance is 3.0 °C/W. An assumption is made that all dissipated power flows through that single heat sink.
b) Individual MOSFET is placed on the individual heat sink, with the sink-ambient thermal resistance is 2.0 °C/W. An assumption is made that each dissipated power from the MOSFETs flows through each heat sink.
Evaluate both designs and choose the most suitable one for the converter. Justify your answer.
Tj.mosfet = 90°C
Tamb = 35°C
NTD12N10
An engineer has to design an AC-DC converter in the figure below with respect to its thermal management. The converter uses MOSFETs for the switching purposes and its characteristics are given in appendix (1). The thermal management designs consideration for the converter are as follows:
a) All MOSFETs are placed on the same heat sink, with the sink-ambient thermal resistance is 3.0 °C/W. An assumption is made that all dissipated power flows through that single heat sink.
b) Individual MOSFET is placed on the individual heat sink, with the sink-ambient thermal resistance is 2.0 °C/W. An assumption is made that each dissipated power from the MOSFETs flows through each heat sink.
Evaluate both designs and choose the most suitable one for the converter. Justify your answer. Tj.mosfet = 90°C
Tamb = 35°C
222 Sin (100t)
NTD12N10
NTD12N10 MOSFET Isterage 175°C
175°C
85°C/W
Rps, s*c
0.14
ID = 6A VGS = 10V 2.5
2
1.5
0.5
50-25
25
5075100125150175 TJ.JUNCTIONTEMPERATURE(C