2N2904A Temperature-Power Derating Curve
PNP General Purpose Transistor. Package, TO-39.
2N2904 Applications; General purpose switching and amplifier circuits
2N2904A Temperature-Power Derating Curve
Use the Graph to determine how much to derate power [wattage] based on ambient operational temperature. Additional Transistor Derating Curves
The graph details the maximum allowable power dissipation with increasing ambient temperature. Maximum operational power dissipation is achievable at 25C. Above 25C the maximum package dissipation, must be reduce to insure that the devices junction temperature remains constant.
Refer to MIL-PRF-19500/290L; Semiconductor Device Transistor, PNP, Silicon, Switching, Types, 2N2904,
2N2904A, 2N2904AL, 2N2905, 2N2905A, and 2N2905AL, JAN, JANTX, JANTXV, JANJ, JANS,
JANTXVM, JANTXVD, JANTXVR, JANTXVH, JANSM, JANSD, JANSR, and JANSH, [TO-39, Hermetically Sealed can]
Screening and processing per MIL-PRF-19500, Qualification Levels per JAN [above].
2N2904 Maximum Ratings:
Collector Emitter Voltage = 40 volts
Power Dissipation 250C = 600mW
Operating Temperature = -65 to +2000C [maximum operational temperature]
How to interpret the chart;
At no time should the junction temperature of the 2N2904 exceed 200C. Select the desired junction temperature [below 200C]. Draw a line parallel to one of the curves to determine the functional operation of the 2N2904 over temperature.
List of Transistor Manufacturers, Small Metal Can Heat Sink Manufacturers, Star style
How to Derate; Electronic Components
