Using a resistor to limit the current can be used for small LEDs. For such low power LEDs, where the supply current is not critical it works okay. But for high-power LEDs, a better way is to use the Constant Current Driver. As the name suggests, the constant current driver will supply the same current whatever voltage it is supplied with and whatever the forward voltage … [Read more...] about Constant Current Driver Design based on LM317
Projects
Automatic Irrigation System Using Arduino
In this project, we will make an automatic irrigation system using Arduino microcontroller. Automatic Irrigation system monitors the soil moisture and depending on set points turns on/off the pump which is connected to the relay. This way you can keep soil moisture to a set point. This system automatically waters the plants when we are on vacation. As we are setting the soil … [Read more...] about Automatic Irrigation System Using Arduino
Arduino DC Digital Voltmeter
A voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit. Analog voltmeters move a pointer across a scale in proportion to the voltage of the circuit; digital voltmeters give a numerical display of voltage by use of an analog to digital converter. We are using internal ADC of Arduino to make Digital Voltmeter … [Read more...] about Arduino DC Digital Voltmeter
Controlling a Servo Motor with Arduino
A servomotor is also defined as a rotary actuator that allows for very fine control of angular positions. This article explains controlling a servo motor with Arduino in detail. Many servos are widely available and quite cheap. Servos can drive a great amount of current. This means that you wouldn't be able to use more than one or two on your Arduino board without using an … [Read more...] about Controlling a Servo Motor with Arduino
Arduino based Automatic Light Controller
The automatic light controller offers energy saving and convenience in the areas with a photosensor (LDR). LDR senses the ambient light conditions in the surrounding area and switches ON-OFF the lighting load. The darkness level in the surrounding is settable. It is in-built with an additional PIR Sensor which TURNS ON Light in the presence of human and switches OFF after 10 … [Read more...] about Arduino based Automatic Light Controller