Authorization encryption circuit and authorization encryption method

The embodiment of the invention provides an authorization encryption circuit and an authorization encryption method, and the authorization encryption circuit comprises a command decoding module which is configured to decode a received command address signal, generate an authorization encryption entry signal if a first preset condition is met, and generate an authorization encryption exit signal if a second preset condition is met; and the authorization encryption module is configured to receive an authorization encryption entry command and an authorization encryption exit command, if the authorization encryption entry command is valid, the read-write command is shielded, and if the authorization encryption exit command is valid, the read-write command is normally operated. By judging whether the command address signal meets the preset condition, the DRAM is controlled to enter the authorized encryption mode and shield the read-write command, or the DRAM is controlled to exit the authorized encryption mode and