2N3418 Temperature-Power Derating Curve [2N3419, 2N3420, 2N3421]
NPN Medium Power Switching Silicon Transistor. Package, TO-39, TO-5 Metal Can.
2N3418 Derating Curve, Maximum Operation
Use the Graph to determine how much to derate power [wattage] based on ambient operational temperature. Transistor Derating Curves
Temperature derating is a standard design practice for electrical engineers.
Refer to MIL-PRF-19500/393H; Semiconductor Device, Transistor, NPN, Silicon Power, Types 2N3418, 2N3418S, 2N3418U4, 2N3419, 2N3419S, 2N3419U4, 2N3420, 2N3420S, 2N3420U4, 2N3421, 2N3421S, and 2N3421U4, JAN, JANTX, JANTXV, JANS, JANSM, JANSD, JANSP, JANSL, JANSR, JANSF, JANSG, JANSH, JANHCA, JANHCB, JANKCA, JANKCB, JANKCBM, JANKCBD, JANKCBP, JANKCBL, JANKCBR, JANKCBF, JANKCBG, and JANKCBH, [TO-39, TO-5]
2N3418 Maximum Ratings:
Collector Emitter Voltage = 60 volts
Power Dissipation 250C = 1Watt
Operating Temperature = -65 to +1750C
How to read the chart; Use the upper curve as a guideline for a 'not to exceed' limit.
Determine the maximum junction temperature that the 2N3418 should operate at.
Draw a line parallel to one of the curves on the chart, that determines the operating characteristics of the 2N3418.
Best practices should force the design to use the 110C curve, for longest life.
How to Derate; Guideline for Derating Electronic Components
