CGY 184
Thermal Resistance and Temperature Considerations:
Because the MW16 heat sink is not easily accessible to a temperature measurment the
thermal resistance is defined as RthJC using the case temperature TC
l Calculation of Junction Temperature TJ :
TJ = TC + RthJC * Ptot
l Measurment of Case Temperature TC :
Tc should be measured in operation at the upper side of the case where the temperature
is highest. Small thermoelements ≤ 1mm (thin wires, thermopaste) and thermopapers
with low heat dissipation are well suited.
Thermoelement for Tcase
Case ( C )
Junction ( J )
PCB
soldered Heatsink
Ambient ( A )
Siemens Aktiengesellschaft
11
Semiconductor Group
11
23.07.97
HL HF19P9E8-G11a-A0s1