BUY HB3051 https://www.utsource.net/itm/p/8933383.html
HB3051 Zener Diodes 5.1V 250mW/0.25W SOT23-5.1V low power
Description: The HB3051 is a 5.1V voltage regulator with a SOT23 package. Features: Low Dropout Voltage Low Quiescent Current Output Current up to 500mA Thermal Shutdown Over Current Protection Output Voltage Accuracy ±2% Output Voltage Range 4.5V to 5.5V Operating Temperature Range -40°C to +125°C Applications: Battery-Powered Systems Automotive Electronics Portable Electronics Industrial Electronics Power Management (For reference only)