From Nicholas Junker on Hackaday.io

Micro TV-B-Gone

The Micro TV-B-Gone is based off of Adafruit’s original TV-B-Gone kit, except made to be as small as possible, using an LIR-2032 coin cell.

I based this project off of the Adafruit TV-B-Gone kit. I wanted to start getting into using surface mount components on my projects, and seeing as the TV-B-Gone was my first foray into soldering, I figured that it would be a great project to work on.
The device takes a rechargeable LIR-2032 battery, and is activated pressing the single button on top. It will run through all TV power codes, and then go into a low power mode, waiting for the next button press. The battery will last around 40 full cycles, before being reduced down to 3.5 volts