Types of Passive STN LCD Displays

Passive STN (Super Twisted Nematic) displays come in three major types:

  1. Segment
  2. Alphanumeric / Character
  3. Graphic

Let’s take a closer look at these 3 types of displays.

What are Passive STN Segment, Alphanumeric, and Graphic Displays?

Segment LCDs

A segment display is the type of thing you see in gas pumps, calculators, or simple meters. It can usually show a few numeric digits and perhaps a few icons or symbols.

Segment display on a scale - crystalfontz.com

These displays are typically used where a very low cost is needed and fixed function display is acceptable. Unless you are making 10K units a month of a very simple, very low-cost device, a segment LCD is probably not the answer.

Alphanumeric / Character LCDs

A character LCD can show a fixed set of numbers and letters in a simple 5×8 dot monospaced font.

The font is stored in the LCD’s controller (the CGROM), so when you want to display an “A”, you simply send over the ASCII code for “A.”

Alphanumeric / character LCDs are typically a nice combination of low cost, good function, and ease of application.

Crystalfontz 20x4 display

Graphic LCDs

A graphic LCD has a regular array of dots, that can be turned on in any pattern to show any image, letters, numbers, or symbols. Graphic LCDs offer the most flexibility, but take more computing power, since every single dot has to be managed.

The current generation of embedded microcontrollers is quite powerful though, and most can easily handle the extra load of a graphic LCD.

A graphic LCD is the best solution to assure that you have future flexibility in your user interface design.

Questions about These Types of LCDs?

If you have any questions about these types of displays or would like help choosing the type of display module would work best for your project, please contact our knowledgeable and friendly support staff by email, phone, or chat.