Smart IR is patented technology I came up with to make an Android Phone to work like an IR remote control. It has shipped in over 650 Million phones.
The Peel Smart Remote is an android application that lets you use your smartphone as a remote control to control your TV, Set top box, air conditioner, anything that you use a remote control for. Adding infra-red (IR) remote control feature to a phone required adding hardware circuitry, and an IR LED (like the one on the top of your TV remote) to the phone.
The Innovation I came up with is called SmartIR, it dramatically reduced the cost of adding the IR remote control feature to an android phone.
The Problem
The Samsung Galaxy S4, launched in 2013, was the first android phone with an IR remote control feature. The cost for Samsung to include this feature was over $1.2 per phone. The Peel application was preloaded on that phone, which meant that anybody who purchased the phone did not need to go to a play store to download the app, it was already available on their phone.
Peel wanted to make sure that the Peel Smart Remote application was the only app preloaded on any phone that had the IR remote control feature.
Background on IR Remote Control Technology:
The hardware circuit in your TV remote control is a microcontroller that will toggle the IR led on and off in a predetermined sequence when you press a button on a remote control. Your TV recognizes the sequences of pulses as a command, and executes it.
Think of an IR remote command like a barcode, the kind that you see on the back of a book or on the packaging of almost anything you buy. A barcode is a sequence of alternating black and white bars of varying thickness that make up a pattern that a barcode scanner can scan and decode.
Every remote code is similar, a series of on and off periods of the infra-red light emitted by the IR LED. If you want to see this in action; pick up your tv remote and point it to your mobile phone’s front (selfie) camera and press a button. The IR light (that you have likely never seen before) will be visible as an oddly purple flicker.
The innovation:
The duration of an IR pulse can vary, from as small as 120 microseconds (0.00012 of a second) to 6 millisecond (0.006 of a second). An IR command is a series of on-off pulses of varying duration, typically up to a total of 200 milliseconds. To accurately send out a remote command requires a dedicated microcontroller that can toggle the LED at a very deterministic rate.
The technology I came up with took away the need to use a dedicated microcontroller, and could use the main processor of the phone to send the IR command without affecting the operation of other applications on the Phone while it was sending it.
All microprocessors big or small include multiple SPI (Serial peripheral interface). This interface allows the main processor to communicate with other devices in the phone, an example is the accelerometer that tells you the orientation of the phone. SPI is typically used to communicate with another processor (or intelligent device) at speeds up to 20 Mhz (20million bits per second).
SPI has no intelligence of its own, there is no way for the bus to know if it is truly connected to another processor. I connected the digital output pin of the SPI BUS to a small circuit that turned the IR LED on or off based on whether the digital output was 1 or 0.
On the main processor I prepare a buffer that has 1’s and 0’s to signal the on and off of the IR LED. Considering that the bus would run at 20Mhz, if I wanted an on period of 120 microseconds I would fill the buffer with 2,400 “1’s”, with filling the buffer with 0’s for the off period and so on, up to total of 200 milliseconds as in a typical IR command.
All processors, big or small, have a feature called DMA (Direct Memory Access). If you fill a large buffer, and hand it over to the DMA system, the processor will continue to send that data at the predetermined SPI BUS speed (in this case 20Mhz) till there is no more data to send.
We patented this approach (8 patents). It took out the need for a dedicated microcontroller in the phone to drive the IR led, bringing the cost of IR down to simply the IR LED, and a small circuit to turn the LED on or off.
The first product to ship with this innovation was the Samsung Note 4 smartphone.
Result:
This innovation brought down the cost of adding IR to between 15 to 25 cents (the cost of the LED, some resistors and a fet). This innovation has been licensed by Samsung, LG, HTC, Xiaomi, Gionee, Oppo, Vivo and many other Android phone OEMs and ODMs. On the Samsung Note 4, this innovation saved them over $1 per device. A savings of over $40 Million.
Having a technology that android OEM needed to license gave Peel the leverage to force the OEMs to preload the Peel Smart Remote application. SmartIR, and the Peel Smart Remote has shipped in over 650 Million android smartphones worldwide.
Samyeer Metrani 