I want to connect my 12v LED circuit powered by an external 12v adapter to my Arduino so I could control the LEDs
First, I'm a beginner in Arduino and have little knowledge on electronics. I know that Arduino Uno can only support 5v and 400mA. I could have easily connected my circuit to it but I'm using 80 LED with a total of 1600mA. As a resort, I found this design (for 50x 2.2v LED just a part of the 80 LED circuit).

Is there a way for me to hook up the 12v circuit to Arduino so that I can control the LED circuit? Any ideas? Suggestion? I have no problem with the LED circuit, I can change it anytime but I want to know how will I be able to connect the circuit to Arduino?