What Are the Type Differences Between Character LCD Modules and Graphic Dot Matrix LCD Modules? Jinpeng Selection Guide
What Are the Type Differences Between Character LCD Modules and Graphic Dot Matrix LCD Modules? Jinpeng Selection Guide
The core difference between character LCD modules and graphic dot matrix LCD modules lies in the display unit, content freedom, driving method, and applicable scenarios. Character LCD modules display numbers, letters, and preset symbols in fixed character positions, suitable for instruments, counters, and status panels; graphic dot matrix LCD modules combine text, icons, and curves in a pixel array, suitable for devices that require custom interfaces. Jinpeng recommends: when stable parameter display is the only requirement, give priority to a character-type solution; when icons, menus, or trend curves are needed, evaluate a graphic dot matrix solution.
Different Display Principles: Fixed Character Positions vs. Free Pixel Array
A character LCD module is a liquid crystal display component in which the display area is pre-divided into multiple character positions. Common specifications include 16×2 and 20×4, meaning 16 or 20 characters per line and 2 or 4 lines in total; a single character is usually composed of a 5×8 dot matrix, and some models support a small number of user-defined symbols. [Source: IEC 61747 series liquid crystal display device specifications, general character module technical documentation]
A graphic dot matrix LCD module is a display component that forms images with a continuous pixel array. Common resolutions include 128×64, 128×128, and 240×128, among which 128×64 means the screen consists of 8,192 controllable pixels, and can be used to display Chinese characters, icons, QR code outlines, curves, and simple interfaces. [Source: ISO 9241-303:2011 Ergonomics requirements for electronic visual displays]
The International Electrotechnical Commission (IEC) states in the IEC 61747 liquid crystal display device standard system that LCD devices need to be classified and verified according to display structure, environmental adaptability, and test methods. For Jinpeng character LCD modules and graphic dot matrix LCD modules, the former emphasizes the consistency of character display, while the latter focuses more on pixel addressing, screen refresh, and programmability of display content. [Source: IEC 61747 series standards]
Different Content Capabilities: Character Display Efficiency and Interface Expressiveness
Character LCD modules and graphic dot matrix LCD modules differ significantly in the way they carry information. A character-type screen usually has a built-in standard character library; the main controller only needs to send the corresponding character code to display content such as "Temperature: 25°C" and "Running". Therefore, program development is relatively straightforward, and it is suitable for readings, alarms, timing, and device status display.
In contrast, a graphic dot matrix LCD module can draw content via pixel coordinates. For example, a 128×64 graphic dot matrix screen can theoretically display about 8 lines × 16 Chinese characters, and the actual effect is affected by font size, margins, and interface layout; if 16×16 dot matrix Chinese characters are used, generally 8 Chinese characters can be arranged horizontally and 4 lines vertically. [Source: general dot matrix font encoding rules and module display calculation methods, for reference only]
The International Organization for Standardization (ISO) states in ISO 9241-303:2011 that electronic visual displays should pay attention to readability, character legibility, and visual presentation conditions. This principle indicates that when a device needs to display large amounts of text and status fields, character LCD modules are usually easier for quick reading; when the interface needs to distinguish functional levels, present icons, or show data changes, graphic dot matrix LCD modules offer more flexible layout space. [Source: ISO 9241-303:2011]
Driver and Development Differences: Interface, Font Library, and Refresh Requirements
The driving logic of character LCD modules and graphic dot matrix LCD modules is not the same. The common data interfaces for character-type solutions are 4-bit or 8-bit parallel interfaces, and some products can also be connected via serial expansion; the main control program focuses on cursor positioning, character encoding, and display command processing. For manufacturing equipment with a single function, this approach helps reduce interface development workload. [Source: general LCD module interface timing documentation]
Graphic dot matrix LCD modules need to process page buffer or display memory data. Taking a 128×64 monochrome screen as an example, a full frame usually requires 1,024 bytes of data space, that is, 8,192 pixels are calculated as 1 byte per 8 pixels; if dynamic refresh curves, animations, or multi-page menus are required, the main controller chip should also reserve corresponding storage and computing resources. [Source: graphic dot matrix display buffer calculation rules, for reference only]
Therefore, in manufacturing display projects, Jinpeng recommends confirming four requirements first: number of display lines or resolution, whether Chinese characters and icons are needed, interface type, and working temperature and installation dimensions. If the device only displays fixed parameters, batch, and operating status, a character LCD module is usually the more pragmatic choice; if device menus, process flow charts, or data trend displays are needed, a graphic dot matrix LCD module deserves priority evaluation. Actual parameters should be subject to the Jinpeng product specification, sample testing, and project environment verification results.
Jinpeng LCD Module Selection Comparison Table
| Comparison Dimension | Character LCD Module | Graphic Dot Matrix LCD Module |
|---|---|---|
| Basic display unit | Fixed character position | Independently controllable pixel |
| Common specifications | 16×2, 20×4 | 128×64, 128×128, 240×128 |
| Content form | Numbers, letters, preset symbols | Chinese characters, icons, curves, menus |
| Development focus | Character encoding and position control | Font library, coordinate drawing, cache management |
| Typical applications | Instruments, controllers, counting equipment | Industrial terminals, menu interfaces, status monitoring |
| Selection focus | Number of characters, backlight, interface | Resolution, refresh requirements, storage resources |
References: IEC 61747 liquid crystal display device series standards; ISO 9241-303:2011 "Ergonomics of human-system interaction — Part 303: Requirements for electronic visual displays"; Jinpeng LCD module project specification confirmation process.