Friday 17 February 2017

Physical Design Interview Part 7

Tell me about yourself in brief
Inputs to PNR
Do you have knowledge on synthesis
What are the validations and sanity checks you do on the outputs received from synthesis team
Which file will you need to check if you see black box in the screen
Which file you need to check if you see any floating pins and whom should you report in such case
What does .tf file, .db file, .sdc file, .spef file .v files include
What is floor plan and what is done as part of floor plan
How do you fix placement of RAMs 
What is utilization factor and Area
What is fly line analysis
How do you decide the spacing between the macros and standard cells
What are tie cells and can the size of array of tie cells be either increased or decreased? –No
Which layers are preferred for power routing and why?
Which is preferred to be the outer most layer or top layer
What is the UF in floor plan
What is the skew achieved in your project and what is the allowed skew
What is local skew and global skew difference
What are the tools used for PNR
What is high fan out synthesis
What is placement and what do we do in this step
What is NLDM
What is congestion and timing closure
What special physical cells are used  in your project
Purpose of power domains, level shifter cells, isolation cells, Always on cell
Where do we use Always On buffers
How is drive strength and delay relation
What is inversion temperature
How is delay and temperature relation
How is threshold voltage and temperature variations related
What happens when you do congestion driven placement
Where are the buffers placed? What is the functionality of buffers
How do buffers speed up the signal in data or in clock even if it adds delay to the path
What is set up and hold violation
What are the ways to fix the set up violation
Ways to fix hold violation
What is STA and which tool is being used for STA
What are the optimizations done in placement stage
What are the power domains in your project
What is switchable power domain

1 comment:

  1. This is a good checkist. I recently had an interview. I used this for the preparation. I was happy to see that most of the questions I was asked were mentioned here.