If it is a light emitting diode it is there to let you know that the relay is energized. In my experience, when a DC current is removed from a coil, the polarity of the magnetic field reverses and if it weren't for the diode, the relay would "chatter". The diode polarity is oppsite of the actuating voltage.
Quenching diodes are used to protect the control circuit of a relay. Power is applied to a relay's coil to close it. When this power is released there is a backwards flowing pulse that can wipe out solid state devices like transistors, LEDs, chips, etc... The quenching diode is applied in parallel with the relay coil so that the cathode is on the positive side. During normal operation, the diode doesn't conduct and the relay operates normally. When the relay is switched off, the "reversed" back pulse is absorbed due to the low voltage drop of the diode which limits the spike.
SILICON same as any other diode but with different characteristics
With a 10mA forward bias current, if the voltages at the anode and cathode of a diode in a circuit are found to be the same, then the diode most likely to be shorted.
to limit the voltage or regulate the same.
If it is a light emitting diode it is there to let you know that the relay is energized. In my experience, when a DC current is removed from a coil, the polarity of the magnetic field reverses and if it weren't for the diode, the relay would "chatter". The diode polarity is oppsite of the actuating voltage.
no
Quenching diodes are used to protect the control circuit of a relay. Power is applied to a relay's coil to close it. When this power is released there is a backwards flowing pulse that can wipe out solid state devices like transistors, LEDs, chips, etc... The quenching diode is applied in parallel with the relay coil so that the cathode is on the positive side. During normal operation, the diode doesn't conduct and the relay operates normally. When the relay is switched off, the "reversed" back pulse is absorbed due to the low voltage drop of the diode which limits the spike.
If the current through a coil is interrupted, the coil generates a high voltage (such as in the old car ignition coils). The diode provides a path for the current to decay naturally, thus avoiding the high voltage.
diode is a two terminal passive non linear device.
SILICON same as any other diode but with different characteristics
No... Diode block one way... resistor block eitherway.
With a 10mA forward bias current, if the voltages at the anode and cathode of a diode in a circuit are found to be the same, then the diode most likely to be shorted.
You do not want to replace diodes with zener diodes. They are not the same type of device, and the design objective is not the same.
to limit the voltage or regulate the same.
forward drop is the same as any other silicon diode, about 0.7V
A: Actually a transistor have two diode with the base mas a common terminal. the characteristics of these tow diodes however are not the same as a common diode