2N4239 Temperature-Power Derating Curve [2N4238, 2N4237]
NPN Low Power Transistor. Package, TO-39.
2N3439 Applications; General Purpose Amplifiers [GP Amps]
2N4239 Temperature-Power Derating Curve
Use the Graph to determine maximum power dissipation of a 2N4239 based on operational ambient temperature. Attaching a heat sink to the metal can will allow the device to operate at a higher temperature with out the need to reduce power consumption. The graph provides maximum power dissipation in still air at the ambient temperature indicated. Applying forced air will also allow greater power dissipation at a given operating temperature.
Temperature derating is a standard design practice, Transistor Derating Curves.
Refer to MIL-PRF-19500/581B; Semiconductor Device, Transistor, NPN, Silicon, Amplifier Types: 2N4237, 2N4238, AND 2N4239, JAN, JANTX, AND JANTXV, [TO-39, TO-205AD]
2N4239 Maximum Ratings, 250C:
Collector Emitter Voltage = 80 volts dc [Vceo]
Collector Base Voltage = 100 volts dc [Vcbo]
Emitter Base Voltage = 6 volts dc [Vebo]
Power Dissipation = 1 Watt, 250C [Ta, ambient temperature]
Power Dissipation = 6.0 Watt, 250C [Tc, case temperature]
Operating Junction Temperature = -65 to +2000C [Tj]
Storage Temperature = -65 to +2000C [Tstg]
Complementary Device; 2N4236 PNP Transistor
2N4239 Derating Curve Notes:
Top curve is thermal runaway loci and cannot be used as a derate design curve since it exceeds
the maximum ratings for this part. Operating under this curve using these mounting conditions assures the
device will not have a thermal runaway. This is the true inverse of the worst case thermal resistance value
extrapolated out to the thermal runaway point.
DEPARTMENT OF DEFENSE SPECIFICATIONS
MIL-PRF-19500 - Semiconductor Devices, General Specification for.
DEPARTMENT OF DEFENSE STANDARDS
MIL-STD-750 - Test Methods for Semiconductor Devices.
How to Derate; Guideline for Derating Electronic Components
