Contents
What is clock routing?
The clock router connects multiple clocked cells to a single clock generator, ensuring a constant wire length to each clocked cell. It does this by building tree structures in user-specified routing channels, adding serpentine wires if necessary to balance the length.
What is routing in ASIC design?
Routing is the process of creating physical connections based on logical connectivity. Signal pins are connected by routing metal interconnects. Routed metal paths must meet timing, clock skew, max trans/cap requirements and also physical DRC requirements.
Which one of these are features of H tree type clock tree design?
The H-tree shape provides a naturally balanced structure that minimizes skew through its natural routing symmetry that is not as OCV-resistant as a mesh but provides better stability over temperature and voltage corners than regular CTS.
What are the types of global routing?
– Types of routing regions: Horizontal channel: parallel to the x-axis with pins at their top and bottom boundaries. p y p g boundaries. Switchbox: rectangular regions with pins on all four sides.
What is routing in physical design?
Making physical connections between signal pins using metal layers are called Routing. Routing is the stage after CTS and optimization where exact paths for the interconnection of standard cells and macros and I/O pins are determined.
What is power mesh in VLSI?
Power planning means to provide power to the every macros, standard cells, and all other cells are present in the design. Power and Ground nets are usually laid out on the metal layers. For core logic there is a core ring enclosing the core with one or more sets of power and ground rings.
What are clock tree types?
There can be several structure for clock tree:
- H-Tree.
- X-Tree.
- Multi level clock tree.
- Fish bone.
Which is the command to route clock nets?
To route signal nets, you can use standalone commands such as route_zrt_global, route_zrt_detail, and route_zrt_auto, or the route_opt command. After routing signal nets, you can add shielding to the routed clock nets using the create_zrt_shield command.
Can You Shield clock Nets before routing signal nets?
ICC implements clock shielding using nondefault routing rules. You can choose either to shield clock nets before routing signal nets or vice versa.
How to specify a routing rule for a clock tree?
You can specify the clock tree routing rule for a specific clock tree by using the -clock_trees option to specify the clock or for all clocks by omitting the -clock_trees option. By default, the specified routing rule is used for all nets in the clock tree.
How to specify clock tree routing in VLSI?
You can specify the clock tree routing rule for a specific clock tree by using the -clock_trees option to specify the clock or for all clocks by omitting the -clock_trees option. By default, the specified routing rule is used for all nets in the clock tree. However, wide wires are often not required on the nets closest to the clock sinks.