SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

• US 20100299466A1
• Filed: 03/30/2010
• Published: 11/25/2010
• Est. Priority Date: 05/20/2009
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Technology Corporation (Renesas Electronics Corporation)
• Inventors: ASANO, Masahiro, Nishihara, Yuriko
• Granted Patent: US 8,392,731 B2
• Time in Patent Office: Days
• US Class Current: 710/105
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/3234 Power saving characterised by the action undertaken
• CPC Class Codes: G06F 13/36 for access to common bus or bus system
• CPC Class Codes: H04L 12/40013 Details regarding a bus controller
• CPC Class Codes: H04L 12/40039 Details regarding the setting of the power status of a node according to activity on the bus
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

Power supply of ECUs connected to a communication network is optimally controlled so that power consumption is reduced. A transceiver/receiver converts a message of a differential signal received via a CAN bus into a digital signal. A select circuit determines whether the converted message is in a CAN format or a UART format. If it is in the UART format, the select circuit outputs a message to the UART circuit. A UART circuit determines whether the message matches a UART format. If matched, an ID determination circuit determines whether the input message is specifying a CAN ID of its own ECU. If it is the CAN ID of the ECU, the ID determination circuit outputs an enable signal to turn on a regulator and supply power to an MCU and an actuator.

Claims

1. A semiconductor integrated circuit device comprising:

a communication protocol interface serving as an interface of a first communication protocol inputted via a communication bus;

a controller controlling an actuator based on a message inputted via the communication protocol interface;

a first regulator supplying power to the communication protocol interface; and

a second regulator supplying and stopping power to the controller and the actuator based on a control signal outputted from the communication protocol interface, wherein

the communication protocol interface generates the control signal based on a message of a second communication protocol that is different from the first communication protocol transferred from the communication bus.

2. The semiconductor integrated circuit device according to claim 1, wherein

the communication protocol interface includes

a protocol determination unit determining whether the message transferred via the communication bus is a message of the first communication protocol or a message of the second communication protocol, and transmitting the message to the controller if the message is the message of the first communication protocol;

and

an ID determination unit into which the message is inputted when the protocol determination unit determines the message is the message of the second communication protocol, the ID determination unit detecting a recognition number in the message, determining whether the detected recognition number and a recognition number individually allocated to the semiconductor integrated circuit device match, and, if matched, outputting the control signal which operates the second regulator.

3. The semiconductor integrated circuit device according to claim 2, further comprising a timer which measures idle time of the controller when a power-source voltage is supplied to the controller, wherein

the controller outputs a power-off instruction signal to the ID determination unit when the idle time of the controller of a given time elapses, and

the ID determination unit outputs the control signal which stops operation of the second regulator when the power-off instruction signal is received.

4. The semiconductor integrated circuit device according to claim 3, wherein

the communication protocol interface includes a power-supply operation information storage unit storing operation information indicating whether the ID determination unit operated or stopped the second regulator, and,

when the ID determination unit operates the second regulator or stops the second regulator,

the ID determination unit stores the operation in the power-supply operation information storage unit.

5. The semiconductor integrated circuit device according to claim 4, wherein

the controller outputs a communication stop message for stopping communication according to the first communication protocol via the communication bus according to the first communication protocol to all of the semiconductor integrated circuit devices carrying out communication according to the first communication protocol so as to stop the communication of the semiconductor integrated circuit devices, then the controller transfers a message of the second communication protocol via the communication bus to any semiconductor integrated circuit device desired to participate in the communication according to the first communication protocol so as to operate the second regulator of any of the semiconductor integrated circuit device.

6. The semiconductor integrated circuit device according to claim 5, wherein

the semiconductor integrated circuit device caused to stop the communication according to the first communication protocol resumes the communication according to the first communication protocol after a given time set by the communication stop message elapses.

7. The semiconductor integrated circuit device according to claim 5, wherein,

in the semiconductor integrated circuit device caused to stop the communication according to the first protocol,

the operation of the second regulator is stopped until the communication protocol interface transfers a message for operating the second regulator according to the second communication protocol.

8. The semiconductor integrated circuit device according to claim 7, wherein

the controller outputs a system activation message according to the second communication protocol via the communication bus, the message being for operating the first regulator, activating the semiconductor integrated circuit device, and starting communication according to the first communication protocol;

the controller checks whether any plugged-in semiconductor integrated circuit device is present among the activated semiconductor integrated circuit devices; and

,

if the plugged-in semiconductor integrated circuit device is present, the controller acquires, according to the first communication protocol, operation recognition information at least including the recognition number from the plugged-in semiconductor integrated circuit device.

9. The semiconductor integrated circuit device according to claim 8, wherein,

when the semiconductor integrated circuit device is operated by an external trigger, the second regulator does not stop power supply to the controller and the actuator, the controller becomes a standby state, and the communication protocol interface is in a state in which a message according to the second communication protocol can be received.

10. The semiconductor integrated circuit device according to claim 9, wherein,

when the controller detects the external trigger and transitions from the standby state to an operation state,

the controller transfers an activation notification signal, which notifies that the semiconductor integrated circuit device is activated by the external trigger, to the communication bus.

11. The semiconductor integrated circuit device according to claim 9, wherein,

when the controller detects the external trigger and transitions from the standby state to an operation state,

the controller sets the communication protocol interface so that the communication protocol interface starts communication according to the first communication protocol, and, when an inquiry whether the semiconductor integrated circuit device is activated by the external trigger is generated, the controller gives a notification about the activation.

12. The semiconductor integrated circuit device according to any one of claims 11, wherein

the first communication protocol is a communication protocol for a vehicle which is either of CAN or FlexRay.

13. The semiconductor integrated circuit device according to any one of claims 12, wherein

the second communication protocol is either of UART or LIN.