2N3740 Temperature-Power Derating Curve
PNP Power Transistor. Package, TO-66 [U4 Surface Mount].
2N3740 Applications; Drivers, Switches, Medium-Power Amplifiers
2N3740 / 2N3741 Temperature Derating Curve
Use the Graph to determine how much to derate maximum power [in wattage] based on ambient operational temperature [Case Temperature]. The curves work for either the 2N3740 or 2N3741 transistor. For longest life use the gray curves which are the most conservative. Or generate a curve that fits the design, parallel to one of the curves shown. The top curve represents the absolute maximum power dissipation, or the 'not to be exceeded' rating. For more information see How to Read Transistor Derating Curves.
Another method then the curves is to use the linear equation;
Derate above 250C by 0.143 watts/0C.
Additional Transistor Derating Curves [which also provides definitions to terms related to transistor derating].
Temperature derating is a standard design practice for electrical engineers.
Refer to MIL-PRF-19500/441; Semiconductor, Device, Transistor, PNP, Silicon, Power, Types 2N3740, 2N3740U4, 2N3741, and 2N3741U4, JAN, JANTX, JANTXV, JANS, JANHC, and JANKC, [TO-66]
2N3740 Maximum Electrical Ratings:
Collector Emitter Voltage = 60 volts dc [80V for 2N3741]
Collector Base Voltage = 60 volts dc [80V for 2N3741]
Emitter Base Voltage = 7 volts dc
Collector Current = 4 Amps dc
Base Current = 2 Amps dc
Power Dissipation 250C = 25 Watts
Operating Temperature = -65 to +2000C
Transistor Pinout: Terminal 1. Emitter. Terminal 2. Base, Case Collector
Complementary to 2N3766 NPN Transistor
MIL-PRF-19500; Semiconductor Devices, General Specification
MIL-STD-750; Test Methods for Semiconductor Devices