Encryption allows you to protect your proprietary parameters, subcircuits, models, and netlists, and release your libraries to your customers without revealing sensitive information. Your customers can run simulations in the Spectre® circuit simulator with the encrypted netlists – the Spectre circuit simulator does not print any data inside the encrypted blocks. Messages about the encrypted portions of your circuit are suppressed.
Spectre AMS Designer simulator uses two different methods to protect (encrypt) source code, depending on what language you use. These two methods are similar but differ in terms of the commands you use and in the way they are implemented.
|
Language |
Method for Protection |
|---|---|
|
Verilog-A, Verilog-AMS, Verilog (digital), VHDL-AMS, and VHDL (digital) code |
|
|
Spectre code |
You cannot probe any nets that go through an encrypted design unit.
You can use source protection with the AMS Designer simulator and analog solver configuration, Spectre solver using the simulation front end (SFE) parser.
Verilog-AMS Protection
It is not possible to partially protect a purely behavioral Verilog-AMS module or a Verilog-AMS module that contains both structural and behavioral information--if you protect anything in such a module, the entire module is protected. However, it remains possible to use Tcl or VPI to create a probe or to access values in the regions of the module that are not explicitly protected.
Protection Guidelines for Automatically Inserted Connect Modules
Automatically-inserted connect modules (AICMs) behave as follows:
- If the instance master for an AICM is protected, the instances of that master are also protected.
- If an AICM instance is connected to a protected net, the AICM instance is protected.
- If an AICM instance is within a protected instance, the AICM instance is protected.
- If an AICM instance is connected to an implicit net (a net that is undeclared), the AICM instance is protected if the net is protected. If the net is not protected, the AICM instance is not protected.
- All information related to a protected AICM instance is blocked.
Forced Use of CMI 3.0
You can use only a CMI 3.0 device library or a device library compatible with CMI 3.0 in conjunction with source protection. Using an incompatible library in conjunction with source protection causes the simulator to stop immediately during initialization.