BUY LMBZ5231BLT1G https://www.utsource.net/itm/p/11272995.html
LMBZ5231BLT1G Zener Diodes 5.1V 225mW/0.225W SOT23-5.1V marking KE1
Description: LMBZ5231BLT1G is a SOT23-5.1V NPN Bipolar Transistor manufactured by ON Semiconductor. Features: Low collector-emitter saturation voltage Low collector-emitter leakage current High current gain Low noise High switching speed Applications: General purpose switching Low voltage amplifier High frequency oscillator Low noise amplifier High speed switching (For reference only)