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Electronics => Beginners => Topic started by: techguru on December 07, 2017, 07:19:53 am

Title: What is process parameter ???
Post by: techguru on December 07, 2017, 07:19:53 am
Hi to all,,

              Next semester my curriculum will be having VLSI Design. In which process parameter is a term i cant find in given text and reference books. Kindly explain what is process parameter for MOS and CMOS?

I have highlighted the topic which are difficult to find in text book.

Kindly advice me a nice book which is apart from university syllabus for VLSI Design..
Title: Re: What is process parameter ???
Post by: Decoman on December 07, 2017, 09:29:28 am
I don't know much about electronics, but I am interested in language and philosophy.

Could it possibly mean 'process' in the sense of the verb? As if doing something? Like "Go process the parameters for MOS and CMOS!"
Title: Re: What is process parameter ???
Post by: danadak on December 07, 2017, 11:35:11 am
We used gate Threshold, wafer resistivity, gate oxide C, thickness, leakage.....
generally speaking electrical and chemical characteristics you can measure
associated with device fabrication.


Regards, Dana.
Title: Re: What is process parameter ???
Post by: rstofer on December 07, 2017, 05:06:19 pm
As to FPGA building blocks, the discussion probably revolves around the LUTs (Look Up Tables) as these implement the logic functions.  But a LUT isn't just a MUX with several inputs, it also has logic for a carry chain when used as an adder and, generally, a D type flip flop at the output.

There are differences between LUTs and higher cost chips may have more elegant designs.  The number of inputs varies as well.  4 input LUTs used to be the limit, now it is common to have 6 inputs.

Pages 18 and 19 give the description of the Slices (4 LUTS) and the layout of the LUTs themselves for the Artix 7 device by Xilinx.

https://www.xilinx.com/support/documentation/user_guides/ug474_7Series_CLB.pdf (https://www.xilinx.com/support/documentation/user_guides/ug474_7Series_CLB.pdf)

FPGAs also have things like phase locked loops for clock generation as well as static BlockRam and IO drivers/transceivers.
Title: Re: What is process parameter ???
Post by: techguru on December 08, 2017, 12:57:47 am
rstofer sir,
               How to understand different architecture of FPGA or different company has different terms and terminology. How to understand different architecture?
Title: Re: What is process parameter ???
Post by: IanB on December 08, 2017, 01:12:34 am
How to understand different architecture of FPGA or different company has different terms and terminology. How to understand different architecture?

This takes time and experience. It is part of what you attend college to start learning. You will get an introduction in your upcoming college courses and will learn much more over time as your embark on your career. You should expect that much of this is a mystery right now, that is normal when you are a student.

You will find that different companies don't have much difference in terms and terminology otherwise it would be very confusing for engineers who move from one company to another. Technical terms and terminology can be specific to a given industry, but within that industry they are shared.

Your first question: what is a process parameter? Well integrated circuits are manufactured using a manufacturing process. That manufacturing process has many detailed parameters that determine the properties of the products made. Others have given detailed examples.

Your second question: different architecture of FPGA and other IC's? Well, once you understand the processes used to manufacture them, you will find there are only certain ways to construct things. So the possible architecture is constrained by the process, which is why you learn about the processes first.