The BZT52C27S SOD-323 Zener diode with ROHS manufacturing by FOSAN is a type of diode that is used to regulate reverse current. This diode works by acting as a battery when the voltage is reversed, causing it to be blocked off from any further current. The voltage is then stored and regulated by the diode, allowing it to provide a stable output. This diode has a reverse voltage of 27V and a power dissipation of 500mW. It is also RoHS compliant, meaning that it has been designed and produced without the use of hazardous substances. In addition, it features an SOD-323 package, which is optimized for more compact circuit boards. This diode is suitable for many different electronics applications including lighting equipment, automotive systems, and audio amplifiers.