“Learn how to create a circuit to increase the electrical current of the Arduino pins to activate loads that need more electrical current.
Between the several types of Arduino and other Microcontrollers, we have a problem: the low capacity of electrical current sourcing of the pins. Where this value can vary between 6 mA to 40 mA in some models. But be careful, always check the datasheet of your device and check the electrical current sourcing capacity of the pins.
But now, to solve this problem, we will use an electrical current driver circuit and we will present all step by step to you construct your own circuit of simple way.
Through the presented problem, the circuit allows you to drive a load whose electrical current is higher than the pin of the Microcontroller can provide. And for that, we will use a transistor.
The transistor will be used as a switch and will allow greater electrical current capacity for the load. And for this, we will use this circuit, that is presented in Figure 2, connected to the Arduino pin or any other CHIP. This circuit can be replicated to all digital pins.”