arduino - leds in parallel, switched with NPN transistors - Electrical Engineering Stack Exchange
Arduino PWM Led Control
Build a very cheap linear LED driver and plug it to Arduino - Projects & Stories - SmartThings Community
OVNSHVN 10Pcs TM1637 LED Display Module 4 Bits 0.36 Inch Clock RED Anode Digital Tube Serial Driver Board for Arduino - Walmart.com
8×32 MAX7219 Dot Matrix LED Display with Arduino
Android Basics and User Interfaces
Max7219 Led Module 8-digit 7 Segment Digital Led Display Tube For Arduino Mcu Microcontroller Serial Driver 7-segment 3.3v 5v - Integrated Circuits - AliExpress
L1: Turning on an LED - Physical Computing
Plant waterer and led control - Project Guidance - Arduino Forum
Multiplexing With Arduino and the 74HC595 : 14 Steps (with Pictures) - Instructables