Abstract: This invention provides a method of managing secret information that ensures that key information in the discard phase can be invalidated and that the system cannot be started. In method of managing secret information in a semiconductor device, the semiconductor device has an OTP (One Time Programmable) module, a security module and a processor. The OTP module further has an OTP memory for storing a secret information and a lifecycle flag for defining an operation phase and a discard phase, a sequencer for reading information stored in the OTP memory and a register for storing the information read by the sequencer. The security module performs a process by the secret information. The processor requests the process to the security module when changing the operation phase to the discard phase and sends a request to the security module to invalidate the secret information.

Abstract: When the external storage itself is replaced by a legitimate old key by a malicious third party, the security IP cannot recognize that it is the old key and can be easily rolled back, that is, the old key is regarded as the legitimate key and operates. An OTP is provided in the SoC, and the version of the key ring is managed in one control table area. Specifically, predetermined information that is updated in synchronization with the key update is written in the management table area of the OTP, and an authentication value is calculated by associating the predetermined information with a key ring including the update key. The calculated authentication value is added and registered when registering the key ring.

Abstract: It is possible to update firmware of domain masters during travelling. An in-vehicle communication system includes a plurality of domain masters, and a redundant domain master configured to be able to perform alternative operations of the plurality of domain masters. The domain masters transmits operation information to the redundant domain master prior to update of firmware. The redundant domain master executes the alternative operation of the domain master using the received operation information. The domain master receives, after the update of the firmware, operation information generated in the alternative operation from the redundant domain master and operates in the updated firmware.

Abstract: In a system using a device not adapted to a single wire bus, a semiconductor device includes an external terminal to be coupled to a power source terminal of an external device, a port that supplies a power source voltage for the external device to the external terminal, a power manager that controls an output of the port, and a CPU that controls an operation of the power manager.

Abstract: It is possible to update firmware of domain masters during travelling. An in-vehicle communication system includes a plurality of domain masters, and a redundant domain master configured to be able to perform alternative operations of the plurality of domain masters. The domain masters transmits operation information to the redundant domain master prior to update of firmware. The redundant domain master executes the alternative operation of the domain master using the received operation information. The domain master receives, after the update of the firmware, operation information generated in the alternative operation from the redundant domain master and operates in the updated firmware.

Abstract: In a system using a device not adapted to a single wire bus, a circuit such as a power source circuit for the device is needed. A semiconductor device includes an external terminal to be coupled to a power source terminal of an external device, a port that supplies a power source voltage for the external device to the external terminal, a power manager that controls an output of the port, and a CPU that controls an operation of the power manager.

Abstract: A semiconductor device is composed of a first circuit receiving a first power supply voltage; and a second circuit receiving a second power supply voltage. The second power supply voltage is higher than the first power supply voltage. Such device arrangement is effective for reducing the soft error rate, when the second circuit is more susceptive to a soft error than the first circuit, especially when the second circuit is a memory device.

Abstract: A semiconductor device is composed of a first circuit receiving a first power supply voltage; and a second circuit receiving a second power supply voltage. The second power supply voltage is higher than the first power supply voltage. Such device arrangement is effective for reducing the soft error rate, when the second circuit is more susceptive to a soft error than the first circuit, especially when the second circuit is a memory device.