BD808 BD810
Note 1:
There are two limitations on the power handling ability of
a transistor: average junction temperature and second
breakdown. Safe operating area curves indicate IC – VCE
limits of the transistor that must be observed for reliable
operation, i.e., the transistor must not be subjected to greater
dissipation than the curves indicate.
The data of Figure 1 is based on TJ(pk) = 150_C; TC is
variable depending on conditions. Second breakdown pulse
limits are valid for duty cycles to 10% provided TJ(pk)
v 150_C. At high case temperatures, thermal limitations
will reduce the power that can be handled to values less than
the limitations imposed by second breakdown.
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