The BZT52C39 with Single 37V~41V 350mW 39V SOD-123 Zener Diodes ROHS manufactured by Hottech are voltage regulators or voltage references, which are used for reference voltage in circuits. They function as a single-stage voltage regulator and protect any circuit from rising above the zener voltage set. They can also be used as voltage reference for analog to digital converters, switching regulators, and comparators. The device is designed in the SOD-123 package, with a maximum dissipation of 350mW , and a breakdown voltage of 37V~41V . It is RoHS compliant and manufactured by Hottech.