公开(公告)号：US20210263098A1

公开(公告)日：2021-08-26

申请号：US16801447

申请日：2020-02-26

Applicant: Silicon Laboratories Inc.

Inventor： Mudit Srivastava ,  Raghavendra Pai Kateel ,  HengWee Cheng ,  Anil Shirwaikar

IPC: G01R31/3177 ,  G06F21/74 ,  G01R31/317

Abstract: An integrated circuit having a secure domain is disclosed. Circuitry within the integrated circuit is used to select one of a plurality of scan modes. The sequence used to select one of the scan modes also serves to reset all of the flip-flops in the secure domain. In this way, it is impossible for a hacker to use the test modes to shift data from the secure domain out of the integrated circuit. The reset is generated asynchronously upon assertion of a first signal and is terminated upon the assertion of a second signal. The assertion of the second signal also serves to select one of the scan modes. This system cannot be hacked by any method that enters scan mode since it is a hardware based solution.

公开(公告)号：US11320482B2

公开(公告)日：2022-05-03

申请号：US16801447

申请日：2020-02-26

Applicant: Silicon Laboratories Inc.

Inventor： Mudit Srivastava ,  Raghavendra Pai Kateel ,  HengWee Cheng ,  Anil Shirwaikar

IPC: G01R31/3177 ,  G01R31/317 ,  G06F21/74 ,  G01R31/327

Abstract: An integrated circuit having a secure domain is disclosed. Circuitry within the integrated circuit is used to select one of a plurality of scan modes. The sequence used to select one of the scan modes also serves to reset all of the flip-flops in the secure domain. In this way, it is impossible for a hacker to use the test modes to shift data from the secure domain out of the integrated circuit. The reset is generated asynchronously upon assertion of a first signal and is terminated upon the assertion of a second signal. The assertion of the second signal also serves to select one of the scan modes. This system cannot be hacked by any method that enters scan mode since it is a hardware based solution.