If your introduction to digital electronics came more years ago than you’d care to mention, the chances are you did so with 5V TTL logic. Above 2V but usually pretty close to 5V is a logic 1, below ...

If you’re looking to control WS2812 (or Neopixel) LEDs using a microcontroller running at 3.3 volts, you might run into some issues. The datasheet tells us that a logic high input will be detected at ...

Almost all inexpensive commercial LED flashlights use a 4.5V power supply—three AA or AAA batteries—because white LEDs require 3.3 to 3.5V to fully turn on. Thus ...

Most commercial LED flashlightsuse three AAA or AA batteriesin series that produce 4.5V. The batteriesthen drive four white LEDs that connectin parallel. These LEDs can workat voltages as low as 2.7V ...