What is the role of the TVS diode on a hard drive PCB?

The TVS (Transient Voltage Suppression) diode on a hard drive PCB is used to protect the hard drive from power surges and voltage spikes. The TVS diode acts as a safety valve, absorbing excess voltage and preventing it from damaging the internal components of the hard drive. The TVS diode is typically located near the power input of the hard drive, as this is where power surges are most likely to occur. The TVS diode is an essential component for the protection and longevity of the hard drive, as it helps to prevent damage from power fluctuations and other electrical disturbances.