Transistors with built-in Resistor UN5211/5212/52.
UN521D - Silicon NPN epitaxial planer transistor
Transistors with built-in Resistor UN5211/5212/5213/5214/5215/5216/5217/5218/5219/5210/ 521D/521E/521F/521K/521L/521M/521N/521T/521V/521Z Silicon NPN.