This component is a Zener diode with a surface-mount transistor designed and manufactured by LG Electronics. It is made of SOD-323 (1SMB) type plastic-encased package with a rating of 5.9V, 200mW power dissipation. It is RoHS compliant and suitable for various RF, digital, and small signal applications. It features wave & reflow soldering capability and an operating temperature range of -55°C to +125°C. Specifically, it is suitable for applications such as switching regulator control, noise bypassing, protection circuits, ESD protection, and voltage references.