Patent ID: 8219743

Claim:
A semiconductor device comprising: a memory cell array comprising a plurality of memory regions; a plurality of write protect content addressable memories (WPCAMs) corresponding to the plurality of memory regions and containing program prohibition information used to determine whether programming in a corresponding memory region is prohibited or allowed; a plurality of content addressable memories (CAMs) including a first CAM and a second CAM, the plurality of CAMs being configured to contain prohibition information used to determine whether changing the program prohibition information in a WPCAM is prohibited or allowed; a write protected content addressable memory (WPCAM) control circuit, configured to reference prohibition information contained in the plurality of CAMs and operable to prohibit a change of the program prohibition information in a WPCAM based on the prohibition information; and a program control circuit configured to program the plurality of memory regions, wherein the WPCAM control circuit receives as input a WPCAM command and prohibition information from the first CAM to prohibit or allow programming of a WPCAM of the plurality of WPCAMs, further wherein the program control circuit is configured to prohibit or allow programming a memory region based on the program prohibition information contained in the WPCAM corresponding to the memory region.