Semiconductor device

A semiconductor device comprising:

• a nonvolatile memory;
• and
• an interface configured to transfer data to and from the nonvolatile memory, wherein
• the interface includes a security logic unit which controls a security level for the data written to the nonvolatile memory, in accordance with a plurality of preset security codes and a lock code that is written to a specific area in the nonvolatile memory, and
• the security codes include a first security code and a second security code, and wherein
• in a test mode for testing the semiconductor device, the security logic unit sets security ON if the first security code matches the lock code, and sets security OFF if the first security code does not match the lock code, and
• in a normal mode for operating the semiconductor device, the security logic unit sets security OFF if the second security code matches the lock code, and sets security ON if the second security code does not match the lock code.