LCD Module (LCM) and dot matrix LCD module What is the difference

LCD module and dot matrix LCD module difference
Broadly speaking, all components assembled by a liquid crystal display device and an integrated circuit are “modules”, but in fact we usually refer to a “dot matrix liquid crystal display device” Especially because dot matrix liquid crystal display device products in addition to some special high-volume varieties (such as electronic dictionaries, communications products), manufacturers are directly to the user supply of liquid crystal display devices, almost all common type dot matrix liquid crystal display devices are Is processed into modules available to users, it is easy to form a “liquid crystal module” is the “dot matrix LCD module” misunderstanding.
LCD module and dot matrix LCD module introduction
LCD module is a liquid crystal display devices, connectors, integrated circuits, PCB circuit boards, backlight, structural components assembled together. English name is “LCD Module”, referred to as “LCM”, Chinese generally known as “LCD module.” In fact it is a commercial part. According to China’s national standards: Only unassembled integrated components are called “modules”, separable is called “components.” So the standard name should be called “LCD components.” But because people have long been accustomed to call it a “module.”
Liquid crystal display device is a high-tech basic components, although it has been widely used, but for many people, the use of assembly is still difficult. In particular, dot-matrix LCD devices, users will feel it is impossible to start. The special connection method and the special equipment required are also not known and available to all. Therefore, users of liquid crystal display devices hope that some people will do their best to assemble the liquid crystal display device and the control and drive integrated circuit together to form a functional part. With the traditional process can be assembled into a whole system.
First, digital LCD module
This is a type of liquid crystal display devices and special integrated circuits assembled into one of the features, can only display numbers and some identification symbols. Segment LCD devices are mostly used in portable, pocket devices, such as BP machines, telephones, electronic watches, calculators, MP3, etc .; also useful in some instruments, such as car audio, tanker and the like. Due to the small size of these devices, the display part should not be designed as a separate part as much as possible. Even if some applications require a separate display component, it should also have some functions of receiving, processing, Storage delivery and other functions, as they have some common, specific features and welcomed by the market. Common digital LCD module has the following.
1. Counting module
This is a kind of seven-segment liquid crystal display device with different digits and decoding driver, or counter plus the counter display assembly. It has the function of recording, processing and displaying numbers. At present, the main products that can be seen on the market in our country are unit LCD display module driven by CD4055 decoding driver and integrated circuits such as ICM7211, ICM7231, ICM7232, CDl4543, UPDl45001, HD44100 and corresponding liquid crystal display devices Of the 4, 6, 8, 10, 12, 16-bit counting module. In the selection of such counting module must pay attention to the following points:
Clear function: Although called “counting module”, but most of them can not be directly counted. Some of their input ports are only BCD code interface form, some are BCD plus gated end input interface form, there are direct and serial, parallel interface interface form, etc., such as the need to calculate or record a String digital elements, you must also configure the corresponding circuit, of course, there are also counting circuit with a good product on the module.
Look for the structure: liquid crystal display devices have different installation methods and installation structure. Solid, in the selection should pay attention to the structural characteristics, in general, this count module mostly by zebra conductive rubber strips, plastic (or metal) pressure frame and the PCB board will be integrated with liquid crystal display devices and made. The outer leads are solder joints, pins, board pin several. Pay attention to the power: a device should try to use a unified power supply, common liquid crystal display device counting module has a single power supply and dual power supply, 5V and 9V and other different specifications.
2. Metering module
Is a multi-segment LCD devices and has decoding, driving, counting, A / D conversion integrated circuit chip assembled module. Due to the integrated circuit used in A / D conversion function, so you can input analog electrical signals into digital display. We know that any physical quantity, even chemical (such as pH, etc.) can be converted into analog power, so as long as accompanied by a certain number of sensors, this module can achieve any amount of value and display, easy to use. The main types of integrated circuits used in the measurement module are ICL7106, ICL7116, ICL7126, ICL7136, ICL7135, ICL7129, etc. The functions and characteristics of these integrated circuits determine the functions and characteristics of the measurement module. As a measurement of products, according to the regulations must be metered. Approved by the metrology department affixed to the product measurement certificate.
3. Timing module
The timing module uses a liquid crystal display device for the longest history of timekeeping. Assembling a liquid crystal display device with a timing integrated circuit is a fully functional timer. Sound in it there is no finished watch shell, so called the timing module. Although the timing module is very versatile, but common, standard timing module is very difficult to buy in the market, only to electronic watch manufacturers to purchase or order the appropriate core, the timing module and the counting module although the appearance of similar, However, the way they are displayed is different, and the number displayed by the timekeeping module is composed of two digits and two digits. The counting module each digit are arranged in series. Because many timing modules also have timing, control functions, so these modules can be widely assembled to some power, equipment, such as tape recorders, CD machines, microwave ovens, rice cookers and other appliances.
Second, the character dot matrix module
It is composed of character dot matrix liquid crystal display device and special line, column driver, controller and the necessary connections, structural components assembled, can display digital characters and Western characters. This lattice character module itself has a character generator, display capacity, feature-rich. In general, this kind of module can display 8 characters in 1 line or 16 characters in l line. The dot matrix arrangement of such a module is made up of a 5 × 7, 5 × 8 or 5 × 11 array of pixel dot matrix arrangements. Each group is a bit, each with a little interval, there is a line between each line interval, it can not display the graphics, the main specifications as shown in the following table:
Generally in the module control, the driver has a well-established character library CGROM that has been cured 192 characters. It also has a user-defined random memory CGRAM for creating special characters, allowing the user to create 8 5 × 8 dot-matrix characters.
Third, the graphics dot matrix LCD module
This module is characterized by a continuous arrangement of bitmap elements, rows and columns in the arrangement are basically no gaps. So you can display continuous, complete graphics. Since it is composed of X-Y matrix pixels, various characters can be displayed in addition to the display pattern.
1. Row, column-driven type
This is a module that must be connected to a dedicated controller. The module is only equipped with a common row and column driver. In fact, this driver only has a general driving output for the pixel, and the input end generally has only 4 bits or less data input , Shift yuan signal input terminal, latch input terminal, AC signal input terminal, such as HD44100, HD66100 and so on. Such modules must be external control circuit, such as T6963C, SEDl335, etc. can be connected with the computer. This kind of module type is more, the application is wider. Although it requires a self-contained controller, it also leaves the customer free to choose between different controllers.
2. Row, column drive – control type
This is a module that interfaces directly with a computer and directly controls the drive with a computer. The column drivers used in these modules have an I / O bus data interface, which allows the module to be hung directly on the bus of the computer, eliminating the need for a dedicated controller, thereby reducing the overall system cost. For a small number of pixels, the whole function is not much, very familiar with the computer programming software users. However it will take up part of your system’s resources.
3. Row, column control type
This is a built-in controller type bit graphics module. It is also one of the most popular types. Such modules are not only equipped with row and column drivers as in the first category, but also with dedicated controllers such as the T6963C, SED1335 and others. This controller is the LCD driver and the computer interface, which is controlled by the computer in the simplest way, receiving and feedback of a variety of computer information through their own independent information processing to achieve the management of the display buffer, and provide the driver The need for a variety of signals, pulses, manipulate the driver to achieve the module’s display. This controller has its own set of dedicated instructions and has its own character generator CGROM. The user must be familiar with the controller’s detailed instructions in order to make a summary. This module allows users to get rid of the controller design, processing, production and a series of work, and make the computer to avoid cumbersome control of the display, saving the host system’s internal resources. There is also a single-chip integrated drive and control products, mainly for portable products, such as mobile phones, MP3, PDA, electronic dictionaries, handheld POS machines and so on.