interview question related to placement

interview questions related to placement stage:

1. What is placement and what are goals of placement?
2. What are the things to be checked before going to placement stage?
3. What are the inputs and outputs for placement stages?
4. After floorplan DEF is generated as input of placement stage what it contains?
5. What are the challenges faced in placement stages?
6. What are reasons of congestion in the design?
7. What are the different methods of tackling congestion? Where do you find major congestion in your design?
8. How do you tackle congestion in the core area? You have a region with pin density high and the router is not able to route to these pins. How to resolve this issue?
9. How to tackle cell density issue?
10. At what stage do you start looking at your timing reports in the PD flow?
11. How will you check your timing report? What are the things you will look into it in case of timing violation?
12. What are the types of placement?
13. During placement stage how tool will know that your design is getting congestion without doing the actual route?
14. What types of routing is carried out by the tool in placement stage global routing or virtual routing?
15. What happens in global routing?
16. What are the switches in place_opt command and how they are useful?
17. What happens during congestion driven techniques? What are the care should be taken using congestion driven option?
18. What are the types of congestion? And solution to resolve congestion?
19. How to modify physical constraints to reduce the congestion?
20. What happens if you over do keepout margin?
21. How many blockages are there in your design, how will you define the blockages and keepout margins (halo)?
22. What do you mean by logic optimization techniques and give some examples of logic optimization?
23. How do you used blockages techniques to effectively reduce congestion?
24. What is magnet placement?
25. What is multibit banking and why we use it and what are the advantages and disadvantages of that?
26. What is fan-out? What is HFN synthesis why we do it in placement stage? Can we consider clock in HFN during placement stages?
27. How global route will handle congested paths?
28. What do you means by scan chain reordering why we used it?
29. How to qualify the placement stage?
30.