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The equation relating diode voltage and current is: Id = Is*(exp(Vd / n*Vt) - 1) Where: Id = Diode current Is = Saturation current exp() = exponential function (e^) n = Ideality factor Vt = Thermal voltage The relationship between temperature and diode voltage comes from this Vt, the Thermal voltage, which is defined as: Vt = k*T / q Where k = Boltzmann constant (8.617 * 10^−5 eV/K) T = Temperature in Kelvin q = Elemental charge (1.602 * 10^−19 C) Thus, the temperature affects the thermal voltage (an electrostatic voltage across the PN junction), which affects the diode's Id and Vd properties.

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PN junction diode made of silicon is the value of voltage depends exponentially on the current through the diode.?

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