LEDs are as popular as ever in digital displays – both as the display itself and as backlighting.
Multiplexed display - the basics
Multiplexing is a technique used to connect devices – typically LEDs (for displays) or buttons (for keyboards) – in a matrix of addressable rows and columns. The advantage is simplification of hardware due to the reduced number of pins required. Multiplexed displays using seven-segment LEDs remain popular due to low cost and high brightness. A … Continue reading "Multiplexed display – the basics"
7-segment display basics
7 segments 7-segment (or “seven-segment) LED displays are commonly used to display digital information. Each segment consists of one or more LEDs and can be lit independently of all the others to form the digits 0 to 9. A limited range of alphabetic characters can also be formed but these are of mixed case and can be … Continue reading "7-segment display basics"
Alphanumeric LED displays
Alphanumeric LED displays are available in several main variations. The 7-segment numeric display remains the most common of these displays. Many devices including industrial controllers have displayed alpha characters on these displays and while acceptable for some characters (A, b, C, d, E, F, etc.) many characters were comically indecipherable without a code book from … Continue reading "Alphanumeric LED displays"
1602 LCD backlight LED
The popular TC1602A-01T LCD features an LED backlight. The backlight is nominally 5 V but reading the datasheet gives some warnings. It appears that the LED has a forward voltage, of 4.1 V at 100 mA but that there is no current limiting built in. If connected directly to a 5 V supply then excessive current would flow (as predicted … Continue reading "1602 LCD backlight LED"
