公开(公告)号：EP1443338A1

公开(公告)日：2004-08-04

申请号：EP03250662.8

申请日：2003-02-03

Applicant: STMicroelectronics Limited

Inventor： Ravenhill, Paul ,  Dellow, Andrew ,  Hutson, Matthew

IPC: G01R31/3185

CPC classification number: G01R31/31719 ,  G01R31/318555

Abstract: A port protection circuit, in particular for protecting a JTAG port, comprises logic gates which are switchable to allow the JTAG port to access scan chains or a Diagnostic Control Unit (DCU). The gating arrangement is controlled by a protection circuit that requires a private key to be input through the JTAG port to "unlock" a circuit so that the gating components allow connection between the JTAG port and scan chains or the DCU.

Abstract translation: 特别是用于保护JTAG端口的端口保护电路包括可切换以允许JTAG端口访问扫描链的逻辑门或诊断控制单元（DCU）。 门控装置由保护电路控制，该保护电路需要通过JTAG端口输入私钥以“解锁”电路，使得门控组件允许JTAG端口与扫描链或DCU之间的连接。