2N718A Temperature-Power Derating Curve
NPN Silicon Planar Transistor, General Purpose Transistor. Package, TO-18 metal Can.
2N718A Applications; Small single general purpose amplifiers.
Temperature-Power Derating Curves for 2N718 Transistor
Use the curve as a guideline for derating power dissipation based on ambient operating temperature for the 2N718 transistor. The top most curve represents the maximum junction temperature and should not be used as an operating condition. Most circuits should be designed to use one of the gray curves, or at the least below the lower black curve.
Derating Equation; Derate linearly at 10.3mW/ degree C above 250C.
Note the maximum operational temperature in still air is 2000C. A heat sink or air flow may be added to increase the temperature or power rating at a range of temperatures.
The collector is electrically and mechanically connected to the case.
Refer to MIL-PRF-19500/181; Semiconductor Device, Transistor, NPN, Silicon, Low-Power, Types 2N718A, 2N1613, AND 2N1613L, JAN, JANTX, and JANTXV [TO-18, TO-39, TO-5]
2N718A Absolute Maximum Ratings, Tc; 250C:
Veco, Collector Emitter Voltage = 30 V dc
Vcbo, Collector Base Voltage = 75 V dc
Vebo, Emitter Base Voltage = 7 V dc
Ic, Collector Current = 500mA dc
Pt, Power Dissipation 250C = 500mW [2N718A]
Pt, Power Dissipation 250C = 800mW [2N1613]
Tj,Operating Temperature = -65 to +2000C
Tstg, Storage Temperature = -65 to +2000C
2N718 Test Circuit, Pulse Response Test
The schematic shown above details the test setup to measure the pulse response for the 2N718 or the 2N1613 transistors.
Note that the input pulse is a +/- 1 volt square wave with a 15nS pulse width, while the output is +18 to +20 volts DC.
Also note the 1N3064 bias diode [Small Signal Diode], and the different bias voltages used.
