Some Basic Concepts of Electronics

Thermal Voltage:

Thermal Voltage is  the voltage developed  across a P-N junction of a Semiconductor Device at a particular Temperature, if not any voltage is applied across the junction. It is expressed as Vt. The temperature dependency of thermal voltage is expressed as below

                    Vt = KT/q (Volts)

Where,    K= Boltzmann Constant = 1.381x10^(-23) J/K

              T= Temperature in Kelvin
              q = 1.6 x 10^(-19) ev/K
From the above data we can calculate thermal Voltage as Below
                         Vt = T/11600 (Volts)
So, At T = 0K  , Vt = 0 volts ;  At T = 300 K Vt = 26 mv
Thus we can say that Thermal voltage is directly proportional to the temperature across the junction.

Electron Volt(EV):

It is the practical Unit of energy in electronics. It is the amount of  energy that a electron gain during moving through a electric field of 1volt.

                          So, 1 EV = |q| x Pd (Joule)

               where, |q|= 1.6 x 10^(-19)

                                   Pd = 1 Volt 

             So, 1EV= 1.6 x 10 ^(-19) Joule