EYE ON NPI - Würth Elektronik's RGB WL-ICLED Integrated Controller Within LED

Adafruit Industries

This week's EYE ON NPI looks miiiiiighty familiar with those of us who love our colorful lights, it's Würth Elektronik's RGB WL-ICLED Integrated Controller Within LED (https://www.digikey.com/en/product-highlight/w/wurth-electronics/wl-icled-integrated-controller-within-led). WE's take on the 'smart LED' has taken over the electronics industry over the past 15 years. These ubiquitous LEDs can save you time, pins, and cost by simplifying the addition of up to a couple-dozen colorful LEDs, especially when the PCB size is at a premium. Back in my day, if you wanted to add a lot of colorful LEDs to a design, you'd have to use a dedicated LED driver chip. That is, unless your microcontroller had tons of pins, and 10mA drive current - and even then there's a total current-draw limit for the chip package. We still stock some breakouts for these like the TLC5947 (https://www.adafruit.com/product/1429) a 'chainable' SPI board that could drive 8 RGB LEDs and PWM them all for you, often with a set-able constant-current. There's still need for chips like this, but they're often kinda large, and they're not free, so using them was not a light matter. Then came the first - or close to the first - low cost chainable LED driver: the LPD8806 (https://www.adafruit.com/product/306). We wrote a library for this chip in 2011 (https://github.com/adafruit/LPD8806/commits/master/?after=1951478c2c2a8317feab9997cdfddba3728a245a+69), the way this chip worked is it could control two RGB LEDs per, with all PWM handled internally and you only needed 2 pins! This was inexpensive and worked great, but the chips were still a bit large, 14-SOICs. They were superseded by the WS2811 (https://www.adafruit.com/product/1060) which came up with using a Manchester encoding (https://en.wikipedia.org/wiki/Manchester_code) for transport over a single line. These used even less space, and only a single pin, with an SOIC-8 package. However, the real ingenuity is when folks realized they could put the chip INSIDE the LED: and thus was born what we call "NeoPixel" (https://www.digikey.com/en/products/result?s=N4IgTCBcDaIHYFMD2AHAlgDwQGxAXQF8g) a fully chainable smart LED that only uses one pin and no external components. Now all's been right in the world, with dozens of different shapes, configurations and sizes of 'WS2812-compatible' LEDs. But there was one thing missing: a reliable source of smart LEDs. And we should know because we use a lot of these chips: and we try to warn folks that low cost LEDs have differing LED color and brightnesses, are hard to solder and rework, and suffer high failure rates in the field. Worst of all, when one fails all the ones down the line also fail! Until today you just had to cross your fingers and hope that the reel you got was from a 'good batch'. That's why we were excited to see Würth Elektronik's RGB WL-ICLED in DigiKey's NPI list, because WE is known for high quality, reliable products. Unlike most NeoPixel compatibles, this datasheet specifies the LED brightnesses and spectra. It also has RoHS, REACh and Halogen compliance. Finally, you know you'll be getting consistent quality, where each LED solders just as well as last week's or last year's batch. The WL-ICLEDs are available in 4 sizes, including the common 5x5mm and 2x2mm. Würth Elektronik also designed a cool FeatherWing (https://github.com/WurthElektronik/FeatherWings/tree/main/ICLEDFeatherWing) with hundreds of the 2x2mm ICLEDs to demo how to display animations, text, and graphics. (https://www.youtube.com/watch?v=_tCo7FSO1Gk) If you want a NeoPixel compatible LED, with trace-ability, high reliability and known functionality check out Würth Elektronik's RGB WL-ICLED (https://www.digikey.com/en/product-highlight/w/wurth-electronics/wl-icled-integrated-controller-within-led) available right now at DigiKey! Order today and you'll get your ready-to-assemble rainbows by tomorrow afternoon.