A chip, including a selector, a one-time programmable (OTP) device, and a controller, where the controller is separately coupled to a selection end of the selector and the OTP device, and the controller is configured to detect a device value of the OTP device, and provide a first selection signal when the device value of the OTP device is within a first preset range. A first input end of the selector is configured to receive access data, a second input end of the selector is configured to receive a preset invalid value, and an output end of the selector is coupled to the OTP device. The selector is configured to control the data received by the second input end to be output from the output end of the selector when the first selection signal is input.