Note that \(i\) is defined as positive when flowing from p to n. Equation \ref{eq1} is also called the Shockley ideal diode equation or the diode law. At an arbitrary temperature, it is a known constant defined by: where k is the Boltzmann constant, T is the absolute temperature of the p–n junction, and q is the magnitude of charge of an electron (the elementary charge). Here, we derive the ideal diode equation specifically for the case of organic heterojunctions HJs . Later he gives a corresponding equation for current as a function of voltage under additional assumptions, which is the equation we call the Shockley ideal diode equation. The simplest approximation to make is to represent the diode as a device that allows no current through -- that is, it acts as an open circuit -- under reverse bias, and allows an unlimited amount of current through -- a closed circuit -- under forward bias. Then we find that the total current, or the drop in hole current, is. I am looking for the simplest possible derivation of the diode equation. share | cite ... You can work through the derivation, but I think you are after a more intuitive answer to the question. relationship can be derived from the current density equation for the electrons and the holes (Homework). I = I 0 ( e q V / k T − 1) Diode Equation is given as above which I just always took it as a fact in my electrical engineering class. where \(I_S\) is the reverse saturation current. In 1954, Bill Pfann and W. van Roosbroek (who were also of Bell Telephone Laboratories) reported that while Shockley's equation was applicable to certain germanium junctions, for many silicon junctions the current (under appreciable forward bias) was proportional to The Shockley diode equation or the diode law, named after transistor co-inventor William Shockley of Bell Telephone Laboratories, gives the I–V (current-voltage) characteristic of an idealized diode in either forward or reverse bias (applied voltage): The equation is called the Shockley ideal diode equation when n, the ideality factor, is set equal to 1. J It gives a more rigorous form of expression for ideal diodes in general, except that it assumes that the cell is thick enough that it can produce this flux of photons. T 22 0. That is the long base case, and the short base diode is this very close to the junction, close to the depletion region x. A Note that Shockley diodes may be fired in a way other than breakover: excessive voltage rise, or dv/dt. It conducts when it is forward biased and stops conducting when it is reverse biased. Simple Derivation Of Diode Equation Thread starter 03myersd; Start date Apr 16, 2009; Apr 16, 2009 #1 03myersd. {\displaystyle \exp((\phi _{p}-\phi _{n})/V_{\text{T}})} It is equivalent to a thyristor with a disconnected gate. This can be taken into account by adding a resistance in series. : When we assume that V V A latched Shockley diode is re-set back into its nonconducting state by reducing current through it until low-current dropout occurs. , [1] Later he gives a corresponding equation for current as a function of voltage under additional assumptions, which is the equation we call the Shockley ideal diode equation. Where is the saturation current or scale current of the diode the magnitude of the current that flows for negative in excess of a few typically 10 12 a. exp He points out that the current at the p terminal is all holes, whereas at the n terminal it is all electrons, and the sum of these two is the constant total current. This decrease is due to an excess of recombination of electron-hole pairs over generation of electron-hole pairs. I am trying to get an intuitive grasp of the derivation of the ideal diode equation and I am struggling with a couple assumptions although the math itself looks pretty straightfoward. 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