Clamping Diode Protection. 120 000 on order view dates. Transients are steep voltage spikes lasting in the region of 10 100 microseconds that can occur due to lightning strikes inductive load switching and electrostatic discharge.
While it is true that standard diodes and zener diodes can also be used for overvoltage transient protection but they are not as robust as transient voltage suppressor diodes because standard and zener diodes are designed for rectification and. A protection diode placed in parallel with the circuit protects that circuit from esd. Generally this works better as v dd is a stiffer rail for clamping and is not as sensitive to disturbance.
The current path in the diode depends on whether the switch in the relay is closed or opened.
A protection diode placed in parallel with the circuit protects that circuit from esd. In an informal sense clamping diodes refer to diodes used as voltage clamps to protect sensitive components against transients and overvoltages. Using a simple 1n4007 diode is sufficient to suppress large voltage spikes in a 24vdc relay with a diode protection circuit. The actual clamping occurs in roughly one picosecond but in a practical circuit the inductance of the wires leading to the device imposes a higher limit.
