This is an LED driver that requires just three microcontroller pins to control up to 8 7-segment digits or a bar graph display or up to 64 individual LEDs. Manufacturer: MAXIM. Manufacturer's Part Number: MAX7219.
These darlington drivers let you microcontroller output pins handle loads of up to .5a such stepper motors, relays and incandescent bulbs. Each pin is protected by a clamping diode so the IC can be connected directly to inductive loads. In 16-pin DIP package Manufacturer: TOSHIBA. Manufacturer's Part Number: ULN2003AP.