15-05-2017, 09:51 PM
19-05-2017, 09:25 AM
Large-scale integration (VLSI) is the process of creating an integrated circuit (IC) by combining thousands of transistors into a single chip. VLSI began in the 1970s when the semiconductor complex and communication technologies were being developed. The microprocessor is a VLSI device. Prior to the introduction of VLSI technology most ICs had a limited set of functions that they could perform. An electronic circuit may consist of a CPU, ROM, RAM and other glue logic. VLSI allows IC designers to add all this on a single chip.
The history of the transistor dates back to the mid-1920s when several inventors tried devices that were intended to control current in solid-state diodes and turn them into triodes. The success came after World War II, when the use of silicon and germanium crystals as radar detectors led to improvements in manufacturing and theory. Scientists who had worked on radar returned to the development of solid-state devices. With the invention of transistors at Bell Labs in 1947, the field of electronics changed from vacuum tubes to solid state devices.
With the small transistor in their hands, the electrical engineers of the 50s saw the possibilities of building much more advanced circuits. However, as the complexity of the circuits grew, problems arose.
One problem was the size of the circuit. A complex circuit like a computer depended on speed. If the components were large, the cables that interconnect them should be long. The electrical signals took time to get through the circuit, slowing the computer down.
The invention of the integrated circuit by Jack Kilby and Robert Noyce solved this problem by making all components and chip out of the same block (monolith) of semiconductor material. Circuits could be made smaller, and the manufacturing process could be automated. This led to the idea of integrating all components into a single silicon wafer, which led to small-scale integration (SSI) in the early 1960s, to mid-scale integration (MSI) in the late 1960s And then to large-scale integration), as well as VLSI in the 1970s and 1980s, with tens of thousands of transistors on a single chip (later hundreds of thousands, then millions, and now billions.
The history of the transistor dates back to the mid-1920s when several inventors tried devices that were intended to control current in solid-state diodes and turn them into triodes. The success came after World War II, when the use of silicon and germanium crystals as radar detectors led to improvements in manufacturing and theory. Scientists who had worked on radar returned to the development of solid-state devices. With the invention of transistors at Bell Labs in 1947, the field of electronics changed from vacuum tubes to solid state devices.
With the small transistor in their hands, the electrical engineers of the 50s saw the possibilities of building much more advanced circuits. However, as the complexity of the circuits grew, problems arose.
One problem was the size of the circuit. A complex circuit like a computer depended on speed. If the components were large, the cables that interconnect them should be long. The electrical signals took time to get through the circuit, slowing the computer down.
The invention of the integrated circuit by Jack Kilby and Robert Noyce solved this problem by making all components and chip out of the same block (monolith) of semiconductor material. Circuits could be made smaller, and the manufacturing process could be automated. This led to the idea of integrating all components into a single silicon wafer, which led to small-scale integration (SSI) in the early 1960s, to mid-scale integration (MSI) in the late 1960s And then to large-scale integration), as well as VLSI in the 1970s and 1980s, with tens of thousands of transistors on a single chip (later hundreds of thousands, then millions, and now billions.