The 21st century is an era of knowledge-based economy dominated by the information industry. A huge change is taking place in the information field. Its leading force and decisive factor are microelectronics technology. The maturity of the film, especially the deep sub-micron (DSM, DeepSub-Mron) and ultra deep sub-micron (VDSM) technology, has greatly promoted the rapid development of the integrated circuit industry.
The development of integrated circuits has experienced circuit integration, functional integration, technology integration, and today's knowledge integration based on computer hardware and software. This indicates that traditional electronic systems have entered the stage of modern electronic systems, which is also known as entering the 3G era, that is, monolithic The integration degree reaches 1G tube technology'> transistor, the device works at 1GHz, and the data transmission rate reaches 1Gbps.
EDA (Electronic Design AutomaTIon) technology is based on computer-aided design, which combines the latest achievements in application electronics, computer technology, information processing technology, and intelligent technology to realize the automatic design of technology '> electronic products. EDA is the core of modern electronic design technology and plays an important role in modern integrated circuit design. FPGA (Field Programmable Gate Array) is a typical representative of programmable logic devices. Its appearance and increasingly perfect adapt to the digital development wave of today's era. It is widely used in the design of modern digital systems.
EDA technology and FPGA principle
1.EDA technical characteristics
EDA is a revolution in the field of electronic design. It originates from Computer Aided Design (CAD), Computer Aided Manufacturing (CAM), Computer Aided Test (CAT), and Computer Aided Engineering (CAE). Computer AidedEngineering). Using EDA tools, electronic designers start designing electronic systems from concepts, algorithms, and protocols, from circuit design and performance analysis to the entire process of IC layout or PCB layout generation.
EDA represents the latest development direction of today's electronic design technology. Its basic feature is that designers use computer as a tool, according to the top-down design method, the whole system is designed and functionally divided, and the system description level is completed by hardware description language. Design, use advanced development tools to automate logic compilation, simplification, segmentation, synthesis, optimization, place and route (PAR, PlaceAnd Route), simulation and specific target adaptation and program download, which is called digital logic circuit High-level design approach.
As the leading technology in modern electronic system design, EDA has two distinct features: ConcurrentEngineering design and top-down design. The basic idea is to start from the overall requirements of the system, divided into three levels: behavior description (BehaviourDescripTIon), register transfer level (RTL, Register Transfer Level), logic synthesis (LogicSynthesis), gradually refine the design content, and finally complete the overall design. This is a brand new design idea and design concept.
2.FPGA principle
Today, the design methods and design methods of digital electronic systems have undergone fundamental changes, and are being transformed from discrete digital circuits to Programmable Logic Devices (PLDs) and ASICs (ApplicaTIon Specific Integrated Circuits). Both FPGAs and CPLDs (Programmable Logic Devices) belong to the category of PLDs, and they are playing an increasingly important role in the design of modern digital systems.
The FPGA is a digital integrated circuit that is programmed by the user to realize the required logic functions. It not only has the advantages of flexible design, high performance, fast speed, but also has a short time to market and low cost. FPGA design is very similar to ASIC front-end design. FPGA applications are becoming more and more popular in the field, and have become the most dynamic and promising industry in integrated circuits. At the same time, with the improvement of design technology and manufacturing process, the performance of devices, integration, working frequency and other indicators continue to increase, FPGA has become the first choice for system-level chip design.
The FPGA is developed from PAL (Programmable Array Logic) and GAL (General Array Logic). The basic design idea is to use the EDA development tools to perform system functions using schematics, state machines, Boolean expressions, hardware description languages, etc. And algorithm description, design implementation and generate programming files, and finally implemented by the programmer or download target device.
The FPGA device adopts a logic cell array (LCA) structure and an SDRAM process, wherein the LCA is composed of three types of programmable cells.
(1) Configurable Logic Block (CLB): called the core array, is the basic unit to implement the custom logic function, scattered throughout the chip;
(2) Input/Output Module (IOB, Input/OutputBlock): arranged around the chip to provide a programmable interface between the internal logic and the device package pins;
(3) Programmable Interconnect (PI): Includes connection segments and connections of different lengths. Its function is to connect each programmable logic block or I/O block to form a specific circuit.
There are many manufacturers of FPGAs in the world, but the most influential ones are Xilinx and Altera. The world's first FPGA was first introduced by Xilinx in the mid-1980s. FPGAs produced by different manufacturers have large differences in the size of the programmable logic block, the internal interconnect structure, and the programmable components used. The actual use should be distinguished.
FPGA design application and optimization strategy
1. FPGA design level analysis
FPGA design includes two aspects: description level and description field. The design description is usually divided into six levels of abstraction, from high to low: system layer, algorithm layer, register transfer layer, logic layer, circuit layer and layout layer. There are three different areas of description for each layer: behavior domain description, domain description, and physical domain description.
The system layer is the highest level abstract description of the system, targeting the overall performance of the electronic system. The algorithm layer, also known as the behavior layer, is a functional description of each module after system-level performance analysis and structure partitioning. The functions and behaviors described by the algorithm layer are ultimately implemented using digital circuits. Digital circuits can be viewed essentially as consisting of registers and combinational logic circuits, where the registers are responsible for signal storage and the combinational logic circuits are responsible for signal transmission. The register transfer layer description describes the entire system from the perspective of signal storage and transmission. Registers and combinatorial logic are essentially composed of logic gates, which describe the entire system from the perspective of logic gate combinations and connections.
The various description levels and integrated technical relationships of FPGA are shown in Figure 1. The traditional synthesis tool translates the description of the register transfer level (RTL) into a gate-level description. With the maturity of the new generation of system design theory with behavioral design as the main symbol, high-level integrated technologies capable of transforming system behavioral level descriptions into RTL descriptions are emerging.
As the focus and hotspot of modern integrated circuit design, FPGA design generally adopts the method of top-down, coarse to fine, and step-by-step refinement. The top level of design refers to the overall requirements of the system, and the bottom layer refers to the implementation of specific logic circuits. From the top down, the whole of the digital system is gradually decomposed into various subsystems and modules. If the subsystem is large, it is further decomposed into smaller subsystems and modules, and the layers are decomposed until the sub-modules in the whole system have a reasonable relationship. Easy to design and achieve.
2.Vhdl application in FPGA design
The scale and complexity of integrated circuit design continue to increase. System-level chip design using traditional schematic methods cannot meet the design requirements, and hardware description language (HDL, HardwareDescripTIonLanguage) has many advantages when designing large-scale digital systems. The hardware description language for system behavior level design has become the mainstream of FPGA and ASIC design. The most popular and representative hardware description languages ​​at present are VHDL (VHSICHardware Description Language) developed by the US Department of Defense (DOD) and Verilog HDL developed by GDA (Gateway Design Automation).
VHSIC stands for Very High Speed ​​Integrated Circuit, so VHDL is the very high speed integrated circuit hardware description language. The VHDL syntax is strict. In 1987, it became the IEEE standard, namely IEEE STD1076-1987. In 1993, it was further revised to become IEEE STD 1076-1993.
As an IEEE standard, VHDL has been supported by many EDA companies. Its main advantages are:
â— Strong description ability, support system level, register transfer level and gate level design;
â— It has good readability and portability. Its source files are both programs and documents, which are easy to reuse and communicate.
â— Support top-down design and library-based design;
â— Supports the design of synchronous, asynchronous and random circuits;
â— Independent of process and long life cycle.
The VHDL language is mainly applied to the behavior layer and the register transport layer. These two layers can fully exploit the advantages of VHDL for higher layers. The essence of digital circuits using VHDL is to use a comprehensive tool to transform high-level descriptions into low-level gate-level descriptions, where the synthesis can be divided into three levels: High-Level Synthesis, Logic Synthesis, and Layout Synthesis. (Layout Synthesis).
Special Application safes are safes that are used in special scene and/or with special functions.
Details:
Solid steel construction;
Including data safes, medical safes and jewelry safes;
Electronic & mechanical panels are available;
Equipped with Mechanical Lock for the emergent opening of the safe
Special Application
Biometric Fingerprint Treasure Safe,Intelligent Electronic Safe,Biometric Safes,Fingerprint Treasure Safe
YONGFA INTELLIGENT TECHNOLOGY SECURITY CO., LTD. , http://www.yongfa-safe.com