#2n3055 transistor how to#

Testing, however would require a more definitive measurement. Note that the air temperature is normally be assumed to be the surrounding temperature as found in what ever chassis the 2N3055 is installed in. In an environment of substantially uniform temperature, cooled only by natural air convection, and not materiallyĪffected by reflective and radiant surfaces. Ambient temperature is the air temperature measured below a semiconductor device, The top curve in the graph is the maximum junction temperature, which is normally always shown in any of the derating graphs.Īmbient temperature.

Some data sheets or derating curves may use the case temperature of a 2N3055 while other data sheets may use the ambient temperature around the 2N3055. The 2N3055 is a two-terminal device, the collector forms the case of the device. So it has to be assumed to be the location of the measurement is defined by JEDEC, although that assumption could change the over-all results.

#2n3055 transistor how to#

The military specification that defines how to derate the 2N3055 does not define the location of the temperature probe. The location should be specified by JEDEC, because the temperature will change based on the location of the Thermocouple. Case temperature is that temperature measured at a specified point on the case of a 2N3055 semiconductor device. Another heatsink is shown above.Ĭase temperature.

Note the large cut-outs in the heat sink for terminals 1 and 2 of the 2N3055 transistor. The 2N3055 package may also be called a diamond style package. A type of package outline or case style which provides a method of readily attaching one surface of the semiconductor device to a larger heat dissipater to achieve thermal management of the case temperature. Refer to MIL-PRF-19500 Semiconductor Devices, General SpecificationĬase mount. The Lead-Free version is 2N3055G in a TO-204AA metal package. The collector is electrically connected to the case. TO-3 Pin Out: Lead 1 = emitter, lead 2 = base, lead 3 = collector. Operating Temperature, Junction = -65 to +200 0C Also seen as a TO-204AA case, depending on the vendor or OEM.Ĭollector Emitter Voltage = 70 volts dc Ĭollector Base Voltage = 100 volts dc Įmitter Base Voltage = 10 volts dc Ĭurrent Gain = 20 to 70, Ic =4A, Vce = 4V Refer to MIL-PRF-19500/407 Silicon Semiconductor Device, NPN Power Transistor, Types covered: 2N3055, JAN, JANTX, and JANTXV. The highest curve to the right represents the maximum operating temperature of the 2N3055 and should not be used in the design. Use any of the three lower curves in the graph above, or select a line parallel to one of the curves. Temperature derating is a standard practice for engineers during circuit design. Sockets are available for a TO-3 package, but should only be used during design and testing. In any case for longest life use either of the gray curves.

Fans may be used to induce forced air cooling which will greatly enhance operation over higher temperatures. Note that the curves indicate Case Temperature and applies to free-air. The two styles of heat sinks for a 2N3055 include Rectangular Shape, or Diamond Shape. Refer below for a graphic of one style of heat sink. Extrusion heat-sinks are by far the most common for power amplifiers, and allow the formation of elaborate two-dimensional shapes capable of dissipating large heat loads. Because the collector is connected to the case the device may be directly attached to a heat sink to allow higher temperature operation. Use the curve to determine the amount of power derating based on case temperature. Some vendors may provide a much stricter derating, as this MIL Spec indicates 34.2mW/C for temperatures over 25C. No power reduction is required for temperatures below 25C. 2N3055 Transistor Operational Power Derating Curveĭerate the power dissipation for the 2N3055 by 0.657 W/ 0C for any operating temperature above 25 0C. 2N3055 Applications General-purpose switching, power amplifiers and audio amplifier. Package, TO-3 metal diamond shape package. 2N3055 Temperature-Power Derating Curve and linearly equation.