The maximum (reverse) V EB for most transistors is 5 V. If a greater voltage is used, the base-emitter junction of the transistor is likely to break down. This is the highest voltage that may be applied in reverse across the base-emitter junction of the transistor. Preferably, the circuit supply voltage should always be less than the specified maximum V CEO.

Obviously, this device should not be used in any circuit with a supply exceeding 40 V otherwise the transistor might break town.

8-1, the maximum collector-emitter voltage is specified as V CEO = 40 V. Defines the amount of noise added by the device.į hfe or f αe : Common emitter cutoff frequency - common emitter operating frequency at which the device current gain falls to 0.707 of its normal (mid-frequency) value.į hfb or f αb : Common base cutoff frequency - as above, for common base.įrom the section of the 2N3903-2N3904 data sheet reproduced in Fig. NF : Noise figure - ratio of total noise output to total noise input expressed as a decibel (dB) ratio. H FE : Static forward current transfer ratio - common emitter ratio of dc collector current and base current. V CE(sat) : Collector-emitter saturation voltage - collector-emitter voltage with the device in saturation. I CBO or I CO : Collector cutoff current - dc collector current with the collector-base junction reverse biased and the emitter open-circuited. I C : Collector current - maximum dc collector current. V EBO : Emitter-base voltage - maximum emitter-base reverse-bias dc voltage. V CEO : Collector-emitter voltage - maximum collector-emitter dc voltage with base open-circuited. The maximum transistor ratings must also be adjusted downward for operation at temperatures greater than 25 ☌. For reliability, the maximum ratings should not even be approached. It is very important that these ratings never be exceeded otherwise, failure of the device is quite possible. These are the maximum voltages, currents, and power dissipation that the device can survive without breaking down. The absolute maximum ratings of the transistor at a temperature of 25☌ are listed next. This information is usually followed by mechanical data in the form of an illustration showing the package shape and dimensions, as well as indicating which leads are collector, base, and emitter, (see Fig.

Most data sheets start off with the device type number at the top of the page, a descriptive title, and a list of major applications for the device. To select a transistor for a particular application, the Transistor Datasheet provided by device manufacturers must be consulted.

Transistor data sheets