The LED Node v2 combines a JeeNode with 3 high-power (2A) mosfets. It is narrow (18 x 132 mm) form factor and has been designed as a good in-line fit for standard RGB LED strips.
The LED Node uses mostly through-hole parts, with the SMD MOSFET’s already soldered to the board, so it’s easy to assemble. It includes theATmega328, the HopeRF wireless module, 3 sensitive MOSFETs able to drive easily lengths of RGB LED strips (even types with 30 or 60 LEDs per meter).The MOSFET drive circuits are tied to I/O pins which support hardware PWM, providing independent flicker-free, dimming of each color. A 4-position heavy duty PCB termination matches the connections of standard RGB common-anode (common-positive) strips.
The LED Node takes its logic power from the required heavy duty supply (typically +12V regulated) which is passed on to the LED anodes. This design pays particular attention to handling relatively large currents effectively. There is provision for adding an optional thermistor for active monitoring of the MOSFET temperature, important when driving strips near the maximum (2A) recommended with high duty cycles. With more modest loading (lower maximum currents and/or duty cycle), the MOSFET’s typically stay just hand warm.
Read the ‘analog’ LED strip specification carefully. The series resistors embedded in the strip are there to limit the current draw of the individual series/parallel LED diodes. If in doubt, connect the strip directly to the power supply (that’s 100% duty cycle) and measure the current per color. The sum of these three currents must be less than the rating of the power supply and less than 3*2A, unless you add in the optional thermistor to detect and then limit excessive MOSFET temperatures. For extra long, single colour strips, the MOSFET outputs can safely wire in parallel.
Note that the LED Node does not have the full set of standard JeeNode’s “ports”. Two standard-wiring 6pin headers (Ports 1,4) are there in non-standard positions (board end and side).
- The LED Node Kit contains the ATmega, HopeRF radio module in the frequency of your choice (915 MHz or 434 MHz), 3 SMD power-MOSFET’s, and all the other parts needed to build a LED Node. Standard header pins are suitable for a total average current of only 1A on the common pin. Use direct soldering to the oversized output pads for higher currents. 868 Mhz models are available in Europe at JeeLabs.com.
- Selecting No Radio for the frequency omits the HopeRF radio module.
- The PCB only assembly option is the bare board without any components (selecting a frequency does nothing; there is no radio included). You’ll need to add your own components to create a working LED Node.
- JeeLabs LED Node with RGB LED Strip combines the LED Node with a 1-meter strip or 5-meter reel of RGB LEDs.
- You may also buy LED strips here.
Limited stock is now available, documentation updates during Dec. 2012.
- JeeLabss blog entries this Weblog.
- Documentation and schematics at JeeLabs.org