What is a manufaturing grid ?

 Hi Naadhan,

Cells actually are aligned with the "placement" grid, which is a multiple of the manufacturing grid. The placement grid is really made up of the rows in your floorplan. The rows are composed of SITEs. For example, in the LEF you will see that each std cell references a SITE that is defined either in the std cell LEF or the tech LEF. The std cell SITE will have the same height as your std cells, but the width will be as small as your smallest filler cell. When you create ROWs in your floorplan, you are really laying out a bunch of these SITEs side by side. The std cells then get placed on these rows.

So, as long as you have everything defined correctly - manufacturing grid, SITE definitions, and ROWs in your floorplan, you should always be aligned with the manufacturing grid. Encounter knows what the grid is, and will only place things (cells and wires) on grid. Occasionally, you will find something offgrid - maybe a hand-placed cell, or a hand-routed wire, where you either turned off DRC checks or maybe entered bad coordinates directly into a fp or DEF file. But these days, you really have to work pretty hard to get something offgrid. :-)

Nonetheless, you can always check for any offgrid shapes with Verify Geometry, and of course, your final signoff DRC deck.

I hope this has answered your questions!

- kari

 Hi Naadhan,

Cells actually are aligned with the "placement" grid, which is a multiple of the manufacturing grid. The placement grid is really made up of the rows in your floorplan. The rows are composed of SITEs. For example, in the LEF you will see that each std cell references a SITE that is defined either in the std cell LEF or the tech LEF. The std cell SITE will have the same height as your std cells, but the width will be as small as your smallest filler cell. When you create ROWs in your floorplan, you are really laying out a bunch of these SITEs side by side. The std cells then get placed on these rows.

So, as long as you have everything defined correctly - manufacturing grid, SITE definitions, and ROWs in your floorplan, you should always be aligned with the manufacturing grid. Encounter knows what the grid is, and will only place things (cells and wires) on grid. Occasionally, you will find something offgrid - maybe a hand-placed cell, or a hand-routed wire, where you either turned off DRC checks or maybe entered bad coordinates directly into a fp or DEF file. But these days, you really have to work pretty hard to get something offgrid. :-)

Nonetheless, you can always check for any offgrid shapes with Verify Geometry, and of course, your final signoff DRC deck.

I hope this has answered your questions!

- kari