The BZT52C4V7 is a single Zener diode manufactured by YFW Electronics and is used for dissipating voltage spikes or regulating unwanted voltage in applications such as power supplies, DC to DC converters, LED lighting, and voltage references. It has a maximum voltage rating of 4.4V-5V for 500mW power, enabling it to be used in many types of circuits. In addition, the BZT52C4V7 is RoHS compliant, allowing it to be used in processes with stringent environmental regulations.