Things You Need To Know About Phototriac

Things You Need To Know About Phototriac

While doing PCB design services, for a safer current flow and even distribution of voltage, designers utilize a wide range of electric-switchable devices. These switchable devices include relays, physical switches, SCRs, and analog switches. These are easily available in packages and can be mounted on the concerned PCB layout at an ease. One such switchable device toggled optically or electrically is called triac. If the switchable device is toggled optically then it is known as phototriac. Hence, in this blog, we will clearly understand all the essential things you need to know about phototaric.

Difference Between Triac And Phototriac:

A triac makes the job of the PCB designer easier as it can be implemented to switch on the AC circuit without having an physical switch on the AC line. However, this creates a major issue with safety. On the other hand, a phototriac is performed through an optical signal which is an Infrared (IR) signal. This signal is given as an input with the help of LED. These phototriacs are available in packages where components would receive a DC signal from General-Purpose Input/Output (GPIO) and the output is used to modulate the load current delivery or to activate a standard triac.

Both the components, be it a phototriac or triac are operated in the same way only with the difference in toggling and how they perform depending on the input. Additionally, these phototriacs have a complex construction and are well-suited for the circuits that include line-voltage to load delivery.

These phototriac components are utilized on the layouts that include surface mount or small through hole packages. These elements are not available directly which can be mounted with an external light source. These components include an LED within their package which is used to toggle the phototriac present inside the package. As they fall under the optoisolators category they are also called as optotriacs.

Tips On Using The Phototriac Efficiently:

Here are some tips to use the phototraics successfully in your PCB circuit and to prevent the transients and switch bounces. They are

  1. Use a series resistor and place it on the input LED to optimize the forward current.
  2. Place a capacitor on the input LED to turn-on the dampen.
  3. Include numerous passives at the output for a seamless power delivery at the load.

In some cases, these components can also be used in the depletion mode where they can be modulated into an ON state and drive away the current from the load.

One of the most popular uses of the phototriac is they are used as a modulator to control the power electronic circuits and the power motor. It is also used in the 

  1. Inrush current limiting
  2. Static switching
  3. Optical solid state relays

Hence, these are the essential things that you should know about phototriac. Sunstream the best provider of PCB layout services is your ideal destination in designing and creating an optically stimulated circuit with the help of phototriacs.