Wireless 'Cloud' LED

The 6 addressable LEDs on this circular PCB are driven in sequence by an AVR microcontroller. The color pattern and RF channel are selected by DIP switches on top, and the device is toggled locally by a capacitive touch sensor. A 500mAh rechargeable lithium battery drives the 5V LEDs through a boost converter, and everything else through a 2.7V LDO.

 

When one 'Cloud' lamp  is touched, it continuously transmits a command for a few seconds with the NRF24L01. While off, other 'Cloud' lamps in range will turn on their receiver every few seconds, at an interval slightly shorter than the transmit period. Doing this 'polled RX' technique greatly improves the sleep current of the device, as both the microcontroller, NRF24, and LED power section can sleep continuously except for a few milliseconds per RX period. 

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The 'Cloud' nomenclature may be misleading – this device does not interface with any cloud services, only with other 2.4GHz radios using Nordic's proprietary ESB protocol. The  name comes from a cloud-shaped diffuser that can be placed over the LEDs.