Vishay OPTO Squad

Smartphone / Tablet Remote Control

“At first glance, Samsung’s Galaxy Tab 3 doesn’t seem to fit its $199 price tag. The price of the tablet, which is slated to be released on July 7, is about on par with other tablets that have 7-inch screens, but this device only stores 8GB of data and the screen resolution is only 1024×600 pixels.

In taking a closer look at specs of the new release, however, Samsung has added many other features that could get buyers’ attention and keep shares of the company’s stock from plunging. These features include an IR emitter to control your TV, a slot for a 64GB-compatible microSD card, and various other features that improve entertainment.”    

                                                                                                              ―Philip Woolgar, The Motley Fool, June 26, 2013

As the world’s leading manufacturer of infrared receivers and emitters for remote control, you can imagine how tuned we are at Vishay to the consumer market for remote controls. Today, many set top boxes feature both infrared and RF for remote control. RF for remote control typically operates on the 2.4 GHz radio band and includes Bluetooth Low Power, Zigbee, IEEE802.15.4, IEEE802.11/WiFi, RF4CE, or proprietary protocols. But the only common use of this ISM band in the home is the microwave oven. The advantage of RF resides solely in the fact that the signal can go through walls or, specifically, cabinet doors. Consumers want to be able to hide all those electronics gadgets like a DVD or STB in a cabinet, giving their living rooms a cleaner, more refined look. Consumers used to also want to hide the TV in a cabinet but then CRTs gave way to hyper-thin, huge LCD TVs. No cabinet was large enough for them, so we decided they would make a beautiful wall hanging or an effective fireplace screen. But I digress. The point is that consumers can use an RF remote control to change channels or make movie selections without having to see the STB.

The challenge initially for RF was that the receiver had to tolerate any interference from ISM equipment, and interference from other unlicensed devices operating in this same band. Remote control units can also use frequency bands other than the bands shared with ISM, but such uses require approval on a country by country basis. The frequency hopping spread spectrum method of transmitting radio signals pretty much eliminates RF receivers from receiving unwanted signals from unintended devices. The main reason RF hasn’t been more widely adopted is the absence of an industry standard that allows worldwide compatibility and interoperability between different manufacturers’ solutions. It is next to impossible to make a universal remote that would work with more than one device unless all the devices use the same protocol and differ only by address. RF4CE is working on this.

Infrared remote control is the leading method of remote control. One advantage over RF is that it is line of sight. You point it at the device you want to control. You can’t be in the next room and inadvertently change the channel; no butt calls with IR.  It is extremely low cost, universal remotes abound, and it is an extremely low-power communication method. Multiple protocols and wavelengths can be used to differentiate device from device, light is an unlicensed and uncontrolled medium, so a single, and worldwide design is feasible and common.

Clearly, I think infrared is the way to go. I am admittedly biased because I work for the Optoelectronics group of Vishay Semiconductors.

But Samsung can’t be accused of being biased and they like infrared as much as I do.


Check out all of Vishay’s IR Receivers at

Check out all of Vishay’s Infrared Emitters at .

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This entry was posted on May 15, 2015 by in Articles, Optical Sensors.
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