ID 683068
Date 9/24/2018
Public

## 1.1.9. Multicorner Analysis

The Timing Analyzer performs multicorner timing analysis to verify your design under a variety of operating conditions—such as voltage, process, and temperature—while performing static timing analysis.

To change the operating conditions or speed grade of the current device for timing analysis, use the set_operating_conditions command.

If you specify an operating condition Tcl object, the -model, -speed, -temperature, and -voltage options are available. If you do not specify an operating condition Tcl object, Tcl requires the -model option. -speed, -temperature, and -voltage are optional.

Tip: To obtain a list of available operating conditions for the target device, use the get_available_operating_conditions -all command.

To ensure that no violations occur under various conditions during the device operation, perform static timing analysis under all available operating conditions.

Table 2.  Operating Conditions for Slow and Fast Models
Slow Slowest speed grade in device density Vcc minimum supply (1) Maximum TJ (1)
Fast Fastest speed grade in device density Vcc maximum supply (1) Minimum TJ (1)
Note :
1. Refer to the DC & Switching Characteristics chapter of the applicable device Handbook for Vcc and TJ. values

In your design, you can set the operating conditions for to the slow timing model, with a voltage of 1100 mV, and temperature of 85° C with the following code:

set_operating_conditions -model slow -temperature 85 -voltage 1100

You can set the same operating conditions with a Tcl object:

set_operating_conditions 3_slow_1100mv_85c

The following block of code shows how to use the set_operating_conditions command to generate different reports for various operating conditions.

### Script Excerpt for Analysis of Various Operating Conditions

#Specify initial operating conditions
set_operating_conditions -model slow -speed 3 -grade c -temperature 85 -voltage 1100
#Update the timing netlist with the initial conditions
update_timing_netlist
#Perform reporting
#Change initial operating conditions. Use a temperature of 0C
set_operating_conditions -model slow -speed 3 -grade c -temperature 0 -voltage 1100
#Update the timing netlist with the new operating condition
update_timing_netlist
#Perform reporting
#Change initial operating conditions. Use a temperature of 0C and a model of fast
set_operating_conditions -model fast -speed 3 -grade c -temperature 0 -voltage 1100
#Update the timing netlist with the new operating condition
update_timing_netlist
#Perform reporting