My grandfather was an engineer, and his house had all sorts of neat gadgets in it. One of the things that stood out to me as a child was a lamp you could turn on and dim just by touching a pad that sat on the desk! So since then, I’ve always thought dimmable lamps were cool, especially touch ones. Well, this LED touch controller board from Blinkinlabs features a really cool little chip called the RH6618 that does exactly what I remember my grandfather’s lamp doing!
The RH6618 is essentially a touch controller on a chip. It does capacitive touch sensing and can be configured to respond in one of three modes, depending on how the jumpers on the board are set. This chip perfectly emulates the way my grandfather’s lamp worked — tapping it quickly smoothly fades the lamp up to the last brightness it was set at. Tapping it again quickly fades it off. Holding the pad down while it’s on slowly fades the brightness up, then down, until you reach the brightness you want. It then remembers this level and will turn on at that level the next time it’s used.
My nostalgia for this lamp notwithstanding, this is a well-created board, with input fusing and reverse polarity protection. It can come with terminal blocks pre-installed, which would make adding it to an existing LED lamp a cinch. If I can find a lamp that has a similar shape to the lamp my grandfather had, I might try and re-create it using this board just for nostalgia. The datasheet for the RH6618 is in Chinese, but online translation software does a fairly good job and it has all the detail needed to work with the chip. Blinkinlabs have also released the schematic and design files, which is great! They even explain how to increase the maximum LED current, should you want to. I hope we get to see some cool lamp designs using this board!
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