The BZT52C20 is a Zener Diode with a SOD-123 RoHS package made by Bourne. It is a three terminal component that is designed to act as a voltage regulator, limiting the amount of voltage and current going through a circuit. The BZT52C20 is manufactured in compliance with Restriction of Hazardous Substances (RoHS) regulations, so it does not contain any hazardous materials or substances. The diode has a Vz of 20V and a Pz of 500mW, which makes it suitable for low noise and high frequency circuits. It also has a low forward voltage drop and high total power dissipation, making it suitable for low-voltage applications. It is also highly stable, with a power dissipation of 0.640 watts (typical) and a maximum Zener voltage of 20 volts (± 5%).