LED

Analyzing a battery powered LED tea light with 24h timer functionality. Discovering that it is surprisingly based on a low-cost 8-bit microcontroller integrated into the LED package.

Taking a closer look at the PWM behavior of the WS2812: Why does it have 11 bit PWM resolution when only 8 bits are used for color data?

Dissects a cheap multicolor LED string and its phosphor-converted LEDs, revealing shared driver quirks.

Reverse-engineers a whole-wire LED Christmas string that encodes data on the supply rails, mapping its protocol.

What would it take to build an addressable LED like the WS2812 (aka Neopixel) using only discrete transistors? Time for a small “1960 style logic meets modern application” technology fusion project.

Flashing a LED is certainly among the first set of problems any burgeoning electronics specialist is tackling, may it be by using an ancient NE555 or, more recently, a microcontroller to control the LED. As it turns out, we can turn any trivial problem into a harder one by changing its constraints.

Whenever a logic gate in an integrated circuit switches, it will cause a tiny current spike that can be measured in the supply current. By inspecting the temporal variation it is often possible to deduce information about the construction of the IC. Let’s take a closer look at the WS2812 RGB LED.

Explores analog chaos with Schmitt triggers, filters, and feedback to create Chua-like oscillations on breadboard.

Builds an addressable seven-segment display module using Padauk MCUs, covering protocol details and firmware.

Attempting to build a LED candle with integrated light sensing using the ‘3‑cent MCU’

Analyzing the SK9822 addressable RGB-LED, a clone of the SPI based APA102.

Implementing a touch controller electronic dice on an ATtiny10 using PlexingPlus.

Analyzing a new addressable RGB LED: The SK6812.

Can we reverse engineer the flickering pattern of a real candle to improve artificial candle LEDs? Measuring and analyzing the temporal light output of a real candle.

PlexingPlus - Driving the seven LEDs of a dice using only two GPIO pins and clever multiplexing.

Dissects APA102 timing details to explain start frames, data forwarding, and reliable end-frame clocking.

How to estimate WS2812 string length by measuring supply-voltage sag from the LEDs’ current draw.

Investigating the SPI based the APA102/APA102C LED, outlining its SPI protocol, global brightness control, and fast PWM behavior.

Implementation of the optimized light_ws2812 driver with hand crafted assembly inner loop that bit-bangs LEDs even at 4 MHz without timing violations on an AVR.

Analyzing and understanding the WS2812 timing, protocol tolerances, and hardware behavior to enable a reliable driver implementation.

Reverse-engineering the algorithm of a candle flicker LED by statistical analysis of its light output pattern.