Physical Design Inputs

#Clock definition: To define clock, we need following four mandatory informations.  1. Clock source: it can be a port of the design or be a pin of a cell inside the design. (typically, that is part of a clock generation logic). 2. Period: the time period of the clock. 3. Duty cycle: the high duration (positive phase) […]

puts “Info: PIE VERSION: 2.2.18”  ##Power Intent version ##First thing we do is create power supply port for power & ground and then we define nets with the port defined. create_supply_port vdd_ssc_cx create_supply_net  vdd_ssc_cx -resolve parallel connect_supply_net vdd_ssc_cx -ports vdd_ssc_cx create_supply_port vss_dig create_supply_net  vss_dig -resolve parallel connect_supply_net vss_dig -ports vss_dig ## We have already defined […]

Lets dig more into the .lib file by looking into its contents. Below are the contents of .lib file. We will go through each and every point of this .lib. library(“<timing_library_file_name>”) { ==> library and the name technology (cmos) ; ==> Which technology this is, like this one is CMOS technology. delay_model : table_lookup ; ==> This explains […]

Below are the contents of LEF in details. The explanation is with ##. VERSION 5.8; ## LEF Version BUSBITCHARS “[]”; ## Bus bit char representation DIVIDERCHAR “/”; ## Divide bit char representation ## Units definition for the numbers defined in this LEF. 4000*number in this case. UNITS                DATABASE MICRON 4000; END UNITS ##Manufacturing grid is the lowest […]

VERSION 5.8 ; ## DEF version DIVIDERCHAR “/” ; ##Divider char representation BUSBITCHARS “[]” ; ## Bus bit char representation DESIGN dummy design; ##Design Name (Partition Name) UNITS DISTANCE MICRONS 4000; ##Unit definition ##Before going to next points lets understand the difference between die and core. Die area is total partition area but core area is where cells are being […]

The second part is to understand that, in these input/output pins what are in input categories and what are in output categories like below. Along with this, it defines the pins which helps to transfer the data like buffer named wire. input clk, rst, SE, scan_in; output [7:0] count; output scan_out; wire clk, rst, SE, […]