2N4033 Temperature-Power Derating Curve [2N4029]
PNP Switching Transistor. Package, [TO-39, TO-18].
2N4033 Applications; High-speed switching
2N4033 Transistor Temperature-Power Derating Curves
The derating curve details the maximum allowable power dissipation with ambient temperature. Maximum operational power dissipation is achievable at 250C [or below]. However above 25C the maximum package dissipation must be reduce to insure that the devices junction temperature remains constant.
Heat Sink;
Installing a [clip-on] heat-sink is one method of insuring that the device will operate above the ambient temperature depicted in the curves. Decreasing a components operational limits as temperature is increased is called derating.
Air Flow;
Implementing forced air cooling will also allow the 2N4033 to operate higher that the graph represents, as the power derating curves are for free-air. Free-Air or still-air is air surrounding the device that is not forced [via a fan] or inhibited because the device in placed within a chassis [enclosure] or case.
Altitude;
An additional power reduction must also be accounted for if the device is operated above sea-level. Check the manufacturers data sheet for operation above the altitude of 10,000 feet [or above sea-level].
Heat Sources;
Insure that there are no near-by heat sources producing radiant heat, the graph does not account for heat produce from other sources.
Refer to MIL-PRF-19500/512; Semiconductor Device, Transistor, PNP, Silicon, Switching,
Types 2N4029, 2N4033, 2N4033UA, 2N4033UB, JAN, JANTX, JANTXV, JANS,
JANKC-2N4033, and JANHC-2N4033 [TO-39 metal Can]
Note; links to the alternate surface mount packages to the left.
The 2N4029 is available in a TO-18 package [metal can].
2N4033 Maximum Ratings:
Collector Emitter Voltage = 80 volts dc [Vceo]
Collector Base Voltage = 80 volts dc [Vdbo]
Emitter Base Voltage = 5 volts dc [Vebo]
Collector Current = 1.0 amps dc [Ic]
Power Dissipation 250C = 400mW [Free-Air]
Operating Temperature, Junction = -65 to +2000C [Tj]
Storage Temperature = -65 to +2000C [Tstg]
Note there are two different surface mount devices called out in the standard listed above; a 2N4033-UA and a 2N4033-UB; however neither version is covered here.
