Very Large Scale Integration Design

Very-large-scale integration (VLSI) is the means of creating an IC by coupling thousands of transistors into a single chip. VLSI started in the 1970s when complex semiconductor and communication technologies were being produced. The microprocessor is a VLSI device.

Before the initiation of VLSI technology, most ICs had a restricted set of functions they could perform. An electronic circuit might consist of a CPU, RAM, ROM, and other glue logic. VLSI allows IC designers to unite all of these into one chip. The electronics industry has reached a phenomenal growth over the last few decades, mainly due to the rapid progress in system design applications and large-scale integration technologies. With the arrival of VLSI designs, the number of applications of integrated circuits (ICs) in high-performance computing, controls, image and video processing, telecommunications, and consumer electronics has been rising at a pretty fast pace.

The current cutting-edge technologies such as high resolution and low bit-rate video and cellular communications provide the end-users with a marvelous amount of applications, processing power, and portability. This trend is expected to grow rapidly, with very important implications on VLSI design and systems design. Hence, several vlsi training institutes in bangalore have opened up. It's a boon to a lot of people who are interested in taking up vlsi courses in bangalore.

VLSI Design Flow

As per the VLSI IC Design flow, Specifications come first. They describe abstractly, interface, the functionality, and the architecture of the digital IC circuit to be designed.

Behavioral description is then generated to analyze the design in terms of purpose, performance, compliance with given standards, and other specifications.

RTL description is produced using HDLs and is simulated to test functionality. It is then reformed to a gate-level netlist using logic synthesis tools. A gate-level netlist is basically, a description of the circuit in terms of gates and connections among them, made in such a way that they meet the timing, power and area specifications.

Finally, it comes to the last stage where the physical layout is made, verified and then sent to fabrication.

FPGA – Introduction

FPGA stands for the term “Field Programmable Gate Array”. It contains from ten thousand to more than a million logic gates, with a programmable interconnection. These interconnections are open for users or designers to carry out the given functions easily.

A typical model FPGA chip includes several I/O blocks, designed and numbered according to their function. There are CLB’s (Configurable Logic Blocks) for each module of the logic level composition. CLBs implement the logic operation given to the module. The interlink between CLB and I/O blocks are formed with the support of horizontal routing channels, vertical routing channels and PSMs (Programmable Multiplexers).

The number of CLB it carries only decides the complexity of FPGA. The tasks to be performed by CLB’s and PSM are designed by a hardware descriptive language like VHDL. After programming, CLB and PSM are fixed on the chip and connected with each other through routing channels.

Advantages

- It requires limited time throughout the design process.

- It doesn't rely on any physical manufacturing steps.

- The only disadvantage is, it is costlier than other styles.