Higher the # of layers higher the cost to manufacture. For example, in board layout, you put shields between high speed clock and the data lines because the high speed clock lines might radiate emi noise to other data lines. For this we this reason we will need to synthesize » Antenna Fixing – to avoid device failures due to charge collection, » Metal Density Control Is Your email address will not be published.

It is recommended that you route sensitive nets like clock before the rest of the signal route. Maybe to avoid the congestion the macros need to be flipped? For a particular design running in ICC2 i am getting this error.Error: worst hold violation exceeds 2000 times nominal buffer delays of * (ns).

two macros are placed vertically (like two refrigerators side by side). I have small query. How it is beneficial? Skew is 200Ps and insertion delay is 600Ps You can see that the technology section above has a”pitch” defined for metal1. B. – Dynamic switching power. Also, check this link We want to pick a routing tool that could adapt to future DFM needs  with relative ease. Then Let us take Metal1, Via1, Contact. How can i find out the exact location of all IOpins sitting at core boundary through command mode in cadence tool ? Designer usually gives you the number of layers to used also called Stack. Are they all same? what are the possible causes for routing congestion between two macros.

Two types of shielding methods are considered, passive shielding [2], [3] and active shielding [4].

What are the really important capabilities and future needs? EMI is the energy that causes undesirable response to any equipment and may be generated by sparking on the motor brushes, tension circuits switching, activation of inductive and resistive loads, activation of switches, circuit breakers, fluorescent bulbs, heaters, automotive ignitions, atmospheric discharges an… which metal layers are used for clock routing ?and why? Is I have read somewhere tungsten is used for vias. you got a nice blog ... you can take a look to my blog toohttp://electricalengineering2017.blogspot.com.eg/, Outstanding information on PD for beginners >>>>>> :)Great .... appreciate your patience and knowledge ...if possible give more information using TCL scripts also. Is using routing blockages advisable in this case. — Top metal layers (7,6) are typically used for routing clock and PG(Power/Ground) nets because the area of these layers is less when compared to the others. We can also route groups of nets, and non-default routing rules can also be applied to select nets. IR drop. When global connections are not proper in the design open occurs. Hi, This can be the minimum spacing of the metal itself, but is usually a value greater than the minimum spacing. `pitch = 0.56`. My assumption is that you have completed power routing after the floorplan stage( because that is what I do.). Title: Shielding and Guarding: How to Exclude Interference-Type Noise Application Note (AN-347) Author: Analog Devices, Inc. How can I make sure that routing is always in top layer? Clock Routing : We do not want to upset the skew and delay values for the clock net as much as possible. why would we only use higher metal layers for power and ground rails. Outside work, she is an avid reader and generally loves being lazy. Can SPEF file be used for back annotation…Is there any command in cadence where i can back annotate SPEF file and perform routing …else can u give me an idea about how to do backannotation…. Higher the rigidity tighter is the constraints.

the ioports and why not any other. Sini Post author January 24, 2014 at 11:21 pm. for example for a design we can use upto 8 metal layers, then why will we use metal8 and metal7 for power and ground rails??? Each of them has its Clock Tree Synthesis, After CTS, the routing process determines the precise paths for interconnections. Question 2: How Scan chin reordering can solve Hold violation???? If i want to route certain inputs of instances using higher metal layers is applying routing blockage to that instance a good idea? Inserting a … I will go with: Antenna Violations and rules will be explained in the next article. For this discussion I am going with a traditional routing approach and not considering signal integrity issues.

It does not really matter if you connect the shield to VDD or VSS, you just need to connect it to a low impedance net.