An exact expression for the thermal variation of the emitter base voltage of bi-polar transistors

Over the years, a number of interesting and useful properties concerning the highly predictable nature of the emitter - base voltage of bipolar transistors have been discovered. One such property is that the exact temperature compensation of the transconductance can be realized. This letter will demonstrate another predictable property of the emitter - base voltage in deriving an expression for the emitter - base voltage as a function of temperature in terms of physical constants and the emitter - base voltage at any one temperature. Since a direct attack on this problem quickly produces unwieldy equations, a ´backdoor approach,´ based on the transconductance compensation scheme, is e used.