2N6306T1 Temperature-Power Derating Curve
NPN Power Transistor. Package, TO-3 Metal Can [TO-254AA, TO-257AA].
2N6306T1 Transistor Derating Curve
The above chart details the maximum allowable power dissipation with increasing ambient temperature. Maximum operational power dissipation is achievable at 25C. However above 25C the maximum package dissipation, or power, must be reduce to insure that the devices junction temperature remains constant. The higher the ambient temperature is increased the lower the allowable power dissipation, as depicted in the curves.
Decreasing a devices operational limits as temperature is increased is called derating, in this case derating a devices operational power dissipation vs increasing ambient [surrounding] temperature. This particular graph depicts the derating of a 2N6306T1 transistor in a TO-254AA package.
Additional Transistor Derating Curves for other devices.
Temperature derating is a standard design practice for electrical engineers.
Refer to MIL-PRF-19500/498E; Semiconductor Device, Transistor, NPN, Silicon, Power, Types 2N6306, 2N6306T1, 2N6306T3, 2N6308, 2N6308T1, 2N6308T3, JAN, JANTX, and JANTXV [TO-3, TO-254AA, TO-257AA]
2N6306T1 Maximum Ratings:
Collector Emitter Voltage = 250 volts
Collector Base Voltage = 500 volts
Emitter Base Voltage = 8.0 volts
Power Dissipation 250C = 6 Watts
Operating Temperature = -65 to +2000C
Storage Temperature = -65 to +2000C
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How to Derate; Guideline for Derating Electronic Components
Department of Defense Specifications:
MIL-PRF-19500: Semiconductor Devices, General Specification
MIL-STD-750: Test Methods for Semiconductor Devices
