2N4150 Temperature-Power Derating Curve [2N3419, 2N5237, 2N5238]
NPN Medium Power Switching Silicon Transistor. Package, TO-5 Metal Can.
2N4150 Applications; General Purpose, Low power, High voltage.
2N4150 Transistor Operational Power Derating Curve
Use the Curves to determine maximum operational power based on operational case temperature, derate power as required. In this particular instance the chart is showing case temperature in still air.
Derating charts will shows one of three cases;
ambient temperature [Ta], case temperature [Tc], or junction temperature [Tj].
How to read the chart; First the maximum possible junction temperature [Tj] is 200C, and should not be exceeded. The right most curve allows the device to operate up to 200C, at zero watts. The other curves provide a more conservative design approach to a maximum of 150C or 125C temperature. The design using a junction temperature of 110C would be the most conservative. Pick a maximum junction temperature [below 200C] and run a line parallel to one of the curves to determine the transistors operating range.
Additional Transistor Derating Curves and graphs
Temperature derating is a standard design practice for electrical engineers.
Refer to MIL-PRF-19500/394M; Semiconductor Device, Transistor, NPN, Silicon, Power Switching, Types: 2N4150, 2N5237, 2N5238, 2N4150S, 2N5237S, and 2N5238S, JAN, JANTX, JANTXV, JANS, JANSM, JANSD, JANSP, JANSL, JANSR, JANSF, JANSG, JANSH, JANHCA, JANHCB, JANKCA, JANKCB, JANKCM, JANKCD, JANKCP, JANKCL, JANKCR, JANKCF, JANKCG, and JANKCH, [TO-5 metal package]
2N4150 Maximum Operational Ratings:
Collector Emitter Voltage = 70 volts dc
Collector Base Voltage = 100 volts dc
Emitter Base Voltage = 10 volts dc
Power Dissipation 250C = 1 Watt
Operating Temperature = -65 to +2000C
Storage Temperature = -65 to +2000C
Transistor Manufacturers, Clip-on Heat Sink Manufacturers
TO-5 Pin Out: Lead 1 = emitter, lead 2 = base, lead 3 = collector.
The collector is internally connected to the case.
How to Derate; Guideline for Derating Electronic Components
Refer to; MIL-PRF-19500; Semiconductor Devices, General Specification
