What effect does temperature change have on diode characteristics?
Reverse saturation current (IS) of diode increases with increase in the temperature the rise is 7\%/ºC for both germanium and silicon and approximately doubles for every 10ºC rise in temperature. Thus if we kept the voltage constant, as we increase temperature the current increases.
Why does a diode overheat?
Zener diode is heating due to power dissipation. More the power dissipation more the heat, similar to resistor, for example: 2 ohms resistor carrying current of 1A is dissipation 2W of power. Smoking is due to “excess power dissipation”, i.e you are crossing the limit of maximum power withstanding capacity of Zener.
What is the effect of temperature on diode IV characteristics?
Increasing the temperature makes the diode to “turn ON” at lower voltages. The diode law for silicon – current changes with voltage and temperature. For a given current, the curve shifts by approximately 2 mV/°C. The light blue curve shows the effect on the IV curve if I0 does not change with temperature.
Can a diode overheat?
Diodes can stand more heat than your fingers can. If you can’t hold it for more than 5 seconds, it is getting too hot. If it stops being a diode and conducts equally in each direction, then it is faulty. The power dissipated in a diode depends on the current and voltage.
Why does diode voltage decrease with temperature?
For any intrinsic semiconductor the band gap of the semiconductor decreases as the temperature increases and hence this results as a decrease in the open circuit voltage of the semiconductor.
Why does voltage decrease when temperature increases in semiconductor?
The decrease in the band gap of a semiconductor with increase in temperature is an increase in the energy of electrons in the material. Lower energy is thus required for breaking the bond. The open circuit voltage decreases with temperature decrease because of the temperature dependence of I0.