The BZT52B27S is a SOD-323 RoHS manufactured by Formosa and it is a Zener diode device. The diode is a three-terminal electronic component that restricts the electric current to flow in one direction, and it is used to create electrical stability in different circuits. The BZT52B27S has a nominal reverse breakdown voltage of 27V, and it can be used for a maximum reverse power dissipation, or PZM, of 500 mW. The RoHS compliant indicates that this diode is compliant with the European regulation on the restriction of certain hazardous substances in electrical and electronic equipment. It is the perfect device for a wide range of applications including power supplies, voltage regulation, and protection circuits.