Application Specific Integrated Circuit

Hi readers, welcome to SOC Physical Design blog. Here, we are going to discuss ASIC Design and our main focus on Physical Design part. Before moving towards the main topics, we have to discuss the FUNDAMENTAL related to the design and here we go................ 

ASIC! The first question comes to our mind is that what is ASIC ????????

The Application Specific Integrated Circuit is an integrated circuit which customized for the specific intent of logic rather than the general-purpose use of the chip.

We can implement the ASIC design using different design flow depending on the number of transistors, design complexity and specific to the application.

In the early days of chip design, chips were made of few hundreds of transistors. Today, when technology is upgraded with a higher count of transistors, high performance within a few nanoseconds. The semiconductor industry has been moving from SSI to ULSI (Ultra Large Scaled IC.) along with Bipolar technology to CMOS technology and even move further towards FINFET and FD-SOI technology for lower technology nodes.    

ASIC classified into Full Custom, Semi-Custom, FPGA. We will discuss more on it in the next post. Right now, we can focus on ASIC.

Each design flow has own pros and cons. ASIC design implantation has many challenges - 

• As we move towards deep submicron technology, more transistors need more area and its results in the drop of wafer yield. 

• Process variation affects the functionality of the design. 

• Manufacturing defects and time-to-market pressure.  

• As we move towards lower technology, transistors are leaky when the count is more and its effect on the power consumption of the chip.  

• Timing and design verification of the design is itself a big task (which take 60-70% of the design cycle). 

• High performance of the chip is correlated with increasing frequency. Any signal in the world is not ideal.

We know about Moore’s law which stated that “the density of transistors in a chip doubles in every two years”. But this law itself obsoleted and it’s taken over by the market. Even when we say 65nm technology node, means nearly 65nm channel length of the transistor. But as we move down towards lower technology node 32nm and below, node number has no significance in today’s semiconductor world.

 

At this note of discussion, we wrap this topic and we will meet soon with a new topic which is part of physical design. Thank you, Have a nice day!