Circuit to protect a light element

摘要

A circuit protects a light element and prevents a breakdown of a laser diode (LD) when electric static discharge (ESD) occurs. The circuit protects the light element in a drive to control an operation of the light element, which radiates light onto a disc. Here, the drive includes a switch between an active node of the light element and a predetermined potential so that the switch is short-circuited in a normal state, but is open when the drive operates. The light element is protected from static electricity or a surge voltage in a manufacturing process thereof or under a user environment. As a result, the probability that the light element is broken down is remarkably reduced.