Skip to main content

Important Topics

 1.Lambda-based design rules?

Ans. Layout or Design Rules: Two approaches to describing design rules: Lambda-based rules: Allow first order scaling by linearizing the resolution of the complete wafer implementation. To move a design from 4 micron to 2 micron, simply reduce the value of lambda. Worked well for 4 micron processes down to 1.2-micron processes.






Comments

Popular posts from this blog

Revision session

 10 Years Experienced Physical Design – Rapid Fire 100 Questions Interview Killer Revision Round (Senior / Lead Level) Use these for Qualcomm / Apple / NVIDIA / AMD / Intel / TSMC interviews. Answer in 1–3 lines, confident and practical. ⸻ Floorplan (1–15) 1. What is ideal utilization? No universal value; depends on macros, routing demand, node, timing target. Common start point high-60s to low-70s. 2. Why low utilization can also be bad? Wastes area, increases wirelength, hurts timing, higher die cost. 3. What is macro halo? Keepout around macro for routing/access/placement margin. 4. Channel spacing decided by? Pin density, expected traffic, metal stack, bus width. 5. Why macro orientation matters? Pin alignment and routing efficiency. 6. What makes floorplan good? Short critical paths, balanced whitespace, clean PG, low congestion risk. 7. Why place macros first? They dominate routing and topology. 8. Why edge macro placement common? Frees center for standard-cell routing. 9. Wh...

ERC :ELECTRICAL RULE CHECK

 Today's most important topic in Backend vlsi signoff stage       ERC (electrical rule check) ERC involves checking a design for all electrical connection. Checks such as well and substrate area for proper contact and spacing ,unconnected input or shorted output and one more Gates should not connect directly to supply (Must be connected through TIE high/low cells only) Floating gate errors ,if any gate is unconnected .This could lead to leakage issues. The well geometries need to be connected to power /ground and if PG Connection is not complete or if the pins are not defined ,the whole layout can report errors like"NWELL is not connected to VDD"

Multiple Voltage Design

MODERN TECHNIQUES                                                      Modern IC designs are heavily influenced by the need to minimize power consumption, particularly in the consumer electronics market. The devices' warmth, battery life, and the time it takes to switch on and off the functions of handheld devices are currently being reformed. Therefore, it becomes crucial to implement best practices in chip design to help reduce power consumption in SoCs (System on Chip). The power management of SoCs and RTL designs has a significant impact on the silicon's performance. Power-aware designs are used by industry to achieve power statistics. This blog focuses on multi-voltage design terms that can be used to assess the power performance of silicon in HDL coding. These facilitate the understanding of design parameters while implementing power-consciou...