ULN2803ADWRG4 by Texas Instruments is a peripheral driver with 8 functions, open-collector output, and built-in transient protection. It operates b/w -40 to 85 °C with a max supply voltage of 3 V. Ideal for applications requiring sink current flow direction in a small outline package style.
NPN; Configuration: 8 BANKS, DARLINGTON WITH BUILT-IN DIODE AND RESISTOR; Surface Mount: NO; Maximum Collector Current (IC): .5 A; No. of Elements: 8; Minimum DC Current Gain (hFE): 1000;
N-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Drain-Source On Resistance: 3.5 ohm; Maximum Drain Current (ID): .2 A; Peak Reflow Temperature (C): NOT SPECIFIED;
NPN; Configuration: SINGLE; Surface Mount: NO; Nominal Transition Frequency (fT): 300 MHz; Maximum Power Dissipation (Abs): .5 W; Maximum Collector Current (IC): .8 A;
BSS138LT3G by Onsemi is a N-CHANNEL FET with a min DS breakdown voltage of 50V. It is used for switching applications and has a max drain current of 0.2A and max drain-source on resistance of 3.5 ohm.
NE555D by Texas Instruments is an 8-terminal IC with a supply voltage range of 4.5V to 16V, suitable for analog waveform generation applications. It operates at temperatures from 0°C to 70°C and has a max supply current of 15mA. The package style is small outline, making it ideal for compact electronic designs.