BSS138K-13 by Diodes Inc. is a N-channel FET with 50V DS breakdown voltage, ideal for switching applications. It features single configuration with built-in diode, operating in enhancement mode. With 3 terminals and 0.31A max drain current, it offers high performance in small outline package style.
ULN2803ADWR by Texas Instruments is a peripheral driver with 8 functions, open-collector output characteristics, and built-in transient protections. It operates b/w -40 to 85°C, has a max supply voltage of 3V, and is ideal for buffer or inverter-based applications requiring sink current flow direction.