Question

what are different three main IC Technologies? discuss the advantages of each of them.

Answer 1

The three different IC technologies are 

1.Full custom VLSI

2.Semi-custom ASIC

3.Programmable Logic Devices (PLD)

The advantages of each of them are as follows :

1. Full custom VLSI

• All layers of full custom IC is optimised and will, therefore, get excellent performance.
  
• Full custom VLSI devices are optimised to perform fix function.
• Design, testing, and fabrication take too much efforts.
• The development costs of full custom VLSI is very high.
• Full custom VLSI is a type of digital logic devices.
• Full custom VLSI are hardwired.
• All the logic cells and mask layers of full custom VLSI is customised.
• Full custom IC is small in size.
  
• Full custom IC consume low power.
  
• Full custom IC have excellent performance.
  
• Microprocessors and RAM used in computers are the examples of full custom VLSI.

2. Semi-custom ASIC

• In semi-custom ASIC the lower level is fully or partially built.
  
• The upper level is not built the upper level is finish by the designer. 
  
• The performance of semi-custom ASIC is good.
  
• The size of semi-custom ASIC is good.
  
• The NRE cost of semi-custom cost of semi-custom ASIC is low then full custom IC.
  
• Semi-custom ASIC uses two technology one is standard cell and second is Mask Programmable gate array (MPGA).
• Programming of semi-custom ASIC is done at fabrication level.
• Semi-custom ASIC is advantageous for highest performance in short time.
• Semi-custom ASIC reduces the cost and design time.

3. Programmable Logic Devices (PLD)

• All layers of Programmable Logic devices are built already.
  
• The designer can directly purchase and IC.
  
• Programmable Logic devices have low NRE cost.
  
• Programmable Logic devices are available instantly.
  
• In PLD there is not customised logic cell or mask layer.