An infrared sensor is a device that emits and/or receives infrared waves in the form of heat. While most infrared sensors transmit and receive infrared waves, some can only receive them. These types of infrared sensors are known as Passive Infrared Sensors (PIR sensors) or motion detectors. What is an Infrared Detector? An infrared detector is a pyroelectric sensor that detects the light spectrum’s infrared wavelength. Infrared detectors are usually emitters as well, but this is not always the case. Infrared detectors can be made of a phototransistor, photodiode, or Read More

A solid state relay is a device that controls voltage to allow or prevent a voltage or current from passing through a circuit without using any moving parts. Solid state relays are commonly found in control systems that use large amounts of power and must be switched on and off on a regular basis. Solid state relays can be used for a wide variety of purposes and can be constructed in different ways. How a Solid State Relay Works Solid state relays consist of a control switch that produces an Read More

A Zener diode transfers current forward and backward, while traditional diodes are only capable of transferring current forward. Many different electronic systems use Zener diodes to control their circuit’s voltage levels. While there are several ways of doing this, Zener diodes provide efficient voltage regulation without damaging the diode itself. How Zener Diodes Work For the most part, a Zener diode acts like a regular diode as current moves in a forward direction in its circuit. However, when a large enough voltage is applied to the diode in the reverse Read More

A photodetector is a device that imprints the image of an object or scene onto a material. Photodetectors are made in various ways and can be used for different purposes. Most photodetectors fall into the phototube, thermal detector, or camera category. These photodetectors are used for communication, navigation, and record keeping. Types of Photodetectors Phototube A phototube is a device that contains a chamber and is either filled with gas or vacuumed so that light passes through it. Phototubes are extremely sensitive and detect ultraviolet, visible, and infrared light. They Read More

In a very simple sense, a capacitor is a device that stores energy in an electric field between two charged "plates" for a short period of time. The electric charge is then used or dissipated at an appropriate time. The capacitor essentially works along the same lines as the battery you might find in a flashlight, but with a few minor differences. How a Capacitor Works A capacitor works in a fairly simple fashion. There are two "plates" separated by a material called a dielectric. The dielectric can be made Read More

A rectifier is a device that is able to convert an alternating current into a direct current through a process known as rectification. This device is very important because most electronic devices require direct current. Rectifiers are often used in power supplies (such as the power adapter used in laptop computers) and to detect radio signals as well as fires. A rectifier is the exact opposite of an inverter and can be seen in virtually all electronic devices. Alternating Current Alternating current is a type of electric current that alternates Read More

A momentary switch is one that is capable of turning a device on or off when a user presses it. Momentary switches represent one of two forms of switches, the other being a traditional on/off switch. They are found in many electronic devices and are usually buttons. Momentary switches are a type of biased switch and are available in two types: push-to-make and push-to-break. How a Momentary Switch Works A momentary switch acts as a regular switch in order to connect two metal contacts and complete an electrical circuit. However, Read More