Physical Cell - Boundary Cells

As we have talked about the series of Physical cell, in the last post, we discussed Filler Cells. Today we are going to discuss the Boundary Cell or Endcap Cell.

 

Boundary Cells

• Boundary cells are typical a non-logical cell and it just provides continuous physical connectivity. 
• Once the floorplan is ready, we placed the boundary cells inside the core boundary which are added to the end cell rows. 
• They are connected to power and ground rails in order to ensure that continuous well and implant layer to prevent the DRC. 
• The N-well of cells is properly terminated within the cell to avoid the well-proximity effect. 
• These cells are used to avoid interference from the external signals. 
• Boundary cells are placed on left, right, top, bottom boundaries. 
• Endcap cells placed in the left and right boundaries only. 
• Endcap cell and boundary cell both are same. There is the only difference in usage of cell in different technology nodes.  
• For 40nm and above, we used endcap cells. For 28nm and below, we used boundary cells.

 

 

At this note of discussion, we wrapped up this topic and we will meet soon with a new Physical Cell. Thank you. Have a nice day!!!