Abstract: An encoding circuit encodes a NRZ code into a transmission line code. A decoding circuit decodes the transmission line code into a NRZ code. If an operation-mode specified by a setting signal is a normal-mode, a transmission switching circuit provides transmit-data received from an input terminal to the encoding circuit to output the encoded transmit-data as communication-data from a communication terminal. If the operation-mode is a sleep-mode, the transmission switching circuit outputs the transmit-data received from the input terminal as the communication-data from the communication terminal. If the operation-mode specified by the setting signal is a normal-mode, a reception switching circuit provides the communication-data received from the communication terminal to the decoding circuit to output the decoded communication-data as receive-data from an output terminal.

Abstract: A LIN receiver includes a voltage divider that divides an input voltage and outputs the divided voltage, and a peak hold circuit that outputs a peak voltage of the input voltage. The LIN receiver is configured to generate a threshold voltage to be used for determining a voltage signal of a communication bus. The threshold voltage is generated from a voltage signal of the communication bus such that the peak value of the voltage signal (i.e., equivalent to a battery voltage) is held by the peak hold circuit and divided by the voltage divider. Although the communication bus is connected to an on-vehicle battery of which voltage varies with time, by using the voltage signal of the communication bus, a 5V system ECU can generate a threshold voltage which varies responding to the variation of the battery voltage. Hence, the voltage signal can be determined correctly as either high or low level.

Abstract: In a transceiver, a clock generator generates a second clock synchronized with a first clock. The second clock has a period corresponding to a duration of one bit of a digital signal. When first transmission data is supplied to the transceiver with being asynchronous to the second clock, a sampling timing generator detects start data of the first transmission data as a start timing, and generates sampling timings based on the first clock in response to the start timing. The sampling timings have intervals each of which is defined to correspond to the period of the second clock. The first sampling timing is spaced from the start timing. A sampling module samples, at each of the sampling timings, the first transmission data, thus generating second transmission data synchronized with the second clock.

Abstract: An inter-line switching element formed of a MOSFET is provided between a pair of signal lines. When the level of a differential signal changes from high to low, a control circuit turns on the FET for a fixed period thereby to suppress ringing by decreasing the impedance between the signal lines when the level of the differential signal transitions, and causing the energy of the distortion of the differential signal waveform to be absorbed by the on-resistance of the FET.

Abstract: A connection method for bus controllers is provided which includes using a logic circuit in which if both signal levels of two input terminals are recessive, a signal level of an output terminal becomes recessive, and if at least one of the signal levels of the two input terminals is dominant, a signal level of the output terminal becomes dominant, defining one of the two bus controllers, which are subject to one-on-one connection, as a first controller, defining the other of the two bus controllers as a second controller, connecting a transmitting terminal of the first controller to one of the two input terminals of the logic circuit, connecting a transmitting terminal of the second controller to the other of the two input terminals of the logic circuit, and connecting receiving terminals of the first and second controllers to the output terminal of the logic circuit.

Abstract: The communication system includes a trunk line constituted of first and second signal lines for transmitting differential signals, a plurality of branch lines each branching from the trunk line and connected with a node, and at least one reflection prevention circuit connected between the first and second signal lines. The reflection prevention circuit includes a rectifier circuit configured to inhibit a current from flowing between the first and second signal lines when a voltage between the differential signals is smaller than or equal to a predetermined voltage, and allow a current to flow between the first and second signal lines when the voltage between the differential signals is larger than the predetermined voltage, and a resistive element connected in series to the rectifier circuit between the first and second signal lines.

Abstract: A slave node communicably coupled to a master node via a bus determines determine whether an active communication mode or a passive communication mode is started based on a header transmitted from the master node. The slave node transmits the header and an ID subsequent to the header when it is determined that the active communication mode is started based on the received header. The ID requests active transmission of a response required to be transmitted in the active communication mode upon the slave node having the response. The slave node monitors arbitration on a bus, and transmits the response subsequent to the ID when the slave node wins the arbitration on the bus between the ID transmitted from the slave node and another information transmitted from another slave node communicably coupled to the master node via the bus based on a result of the monitor.

Abstract: In a communication system, plural nodes are communicably connected to a communication line and mutually communicate based on an NRZ (Non Return to Zero) code. Each node detects, as a data frame head, a dominant level when a signal on the line changes to a dominant level during a stand-by state of the line. An activation frame is transmitted during a sleep mode. The activation frame has an activation pattern area storing therein a bit pattern showing that the frame is the activation frame, a specific pattern area storing therein a bit pattern showing a node to be activated, a boundary position satisfying a predetermined boundary condition and being a boundary between the activation and specific pattern areas. Each node performs a switchover from the sleep mode to a normal mode based on the bit patterns in the activation and specific pattern areas and information given by the boundary position.

Abstract: A transmission apparatus for differential communication includes a driver bridge circuit and a pair of noise protection circuits. The driver bridge circuit includes four output devices that are independently connected between each of a pair of transmission lines and a power line or a ground line. Each noise protection circuit is provided to a corresponding transmission lines. Each noise protection circuit includes a ground potential detector and an impedance controller. The ground potential detector detects a potential of the corresponding transmission line with respect to the ground line. The impedance controller causes an impedance of the corresponding transmission line with respect to the ground line to become equal to an impedance of the other transmission line with respect to the ground line, when the detected potential becomes outside a predetermined potential range.

Abstract: A voltage supply unit is provided for a communication system provided with a network including a transmission path that consists of a main line and plural branch lines, which are formed as a differential two-wire type of transmission line consisting of first and second communion lines. This unit comprises a DC voltage source and an application device. The DC voltage source outputs a specified voltage different from a reference voltage of the transmission path. The application device applies, to the transmission path, the specified voltage in response to a command to be given. The unit is provided in a fault diagnosis apparatus or a node connected to the communication system. The specified voltage disables communication of only a certain node and to allow the remaining nodes to communicate with each other. In the certain node, an electrical disconnection is caused in either the first and second communications.

Abstract: The vehicle-use safety control apparatus is configured to operate on electric power supplied from a vehicle battery mounted on a vehicle through at least one of a first electric power supply path interposed with an ignition switch of the vehicle, and a second electric power supply path interposed with a changeover switch. The vehicle-use safety control apparatus includes a running state information acquiring means to acquire running state information on whether the vehicle is running or stopped, and a switch control means to change an on/off state of the changeover switch in accordance with the running state information received from the running state acquiring means.

Abstract: The communication signal generating device is for use in a communication system where communication signals each of which is set at a first level or a second level are exchanged among a plurality of communication apparatuses through a communication line. The communication signal generating device includes a switching element provided in a communication line to connect the communication line to a ground or a constant voltage source, and a driving means to generate a first communication signal at the first level by turning on the switching element to thereby pass a certain current to the communication line, and generate a second communication signal at the second level by turning off the switching element to thereby pass no current to the communication line. The driving means is configured to gradually increase an output impedance of the switching element during one bit time of the first communication signal.

Abstract: When a transmission signal is detected as having been changed from a high level to a low level, two transmission lines are connected for only a predetermined time through a diode by a first transistor and a second transistor. The diode is arranged such that its forward direction is from a high-side transmission line to a low-side transmission line. The diode turns on, when a potential of the high-side transmission line becomes higher than that of the low-side transmission line by ringing and a potential difference therebetween exceeds a forward drop voltage of the diode. As a result, a peak wave level of a positive side in the ringing is limited to the forward drop voltage of the diode.

Abstract: A ringing suppression circuit for a communication circuit that performs communication through a transmission line includes a high side switch connected between a high potential reference point and a high side line of the transmission line, a low side switch connected between a low potential reference point and a low side line of the transmission line, and a ringing suppression section. The ringing suppression section turns on the high side switch based on a difference between a potential of the high side line and a potential applied to a control terminal of the high side switch. The ringing suppression section turns on the low side switch based on a difference between a potential of the low side line and potential applied to a control terminal of the low side switch.

Abstract: A communication signal processing apparatus includes: a transmitted-signal processing unit which, in accordance with a transmitted signal outputted from a communication control apparatus, transmits a communication signal indicating “dominant” via the communication line by applying a current to a communication line, and transmits a communication signal indicating “recessive” via the communication line by not applying a current to the communication line; and a received-signal processing unit which determines whether the communication signal received via the communication line indicates “dominant” or “recessive”, then outputs a received signal indicating the determination result to the communication control apparatus.

Abstract: A LIN receiver includes a voltage divider that divides an input voltage and outputs the divided voltage, and a peak hold circuit that outputs a peak voltage of the input voltage. The LIN receiver is configured to generate a threshold voltage to be used for determining a voltage signal of a communication bus. The threshold voltage is generated from a voltage signal of the communication bus such that the peak value of the voltage signal (i.e., equivalent to a battery voltage) is held by the peak hold circuit and divided by the voltage divider. Although the communication bus is connected to an on-vehicle battery of which voltage varies with time, by using the voltage signal of the communication bus, a 5V system ECU can generate a threshold voltage which varies responding to the variation of the battery voltage. Hence, the voltage signal can be determined correctly as either high or low level.

Abstract: A transmission apparatus for differential communication includes a driver bridge circuit and a pair of noise protection circuits. The driver bridge circuit includes four output devices that are independently connected between each of a pair of transmission lines and a power line or a ground line. Each noise protection circuit is provided to a corresponding transmission lines. Each noise protection circuit includes a ground potential detector and an impedance controller. The ground potential detector detects a potential of the corresponding transmission line with respect to the ground line. The impedance controller causes an impedance of the corresponding transmission line with respect to the ground line to become equal to an impedance of the other transmission line with respect to the ground line, when the detected potential becomes outside a predetermined potential range.

Abstract: A communication system is provided, as one aspect, which includes a communication line and a plurality of nodes connected to the communication line, and has a network which is activated based on specific signals sent from two nodes of the plurality of nodes to the communication line. The system includes: a first cold start node and a second cold start node which are connected to the communication line, and activate the network by sending the specific signals to the communication line; and a third cold start node which is connected to the communication line so as to be positioned between the first and second cold start nodes, activates the network by sending the specific signal together with the first or second cold start node, and determines whether or not communication failure has occurred between the plurality of nodes based on a signal transmitted through the communication line.

Abstract: As one aspect, a communication node is provided which transmits data using an assigned frame. The communication node includes a data information storing section which stores information in which plural types of data storage information are related to identifiers, the data storage information indicating a relationship between one or more time slots configuring a frame and data stored in the time slots, and the identifiers identifying the data storage information. The communication node further includes an identifier selecting section which selects one of the identifiers, an identifier transmitting section which transmits the selected identifier included in a predetermined position of the frame, and a data transmitting section which refers to the data storage information corresponding to the selected identifier and transmits data which is specified by the data storage information and is included in a time slot based on the data storage information.

Abstract: The present invention provides, as one aspect, a communication apparatus which is connected with a communication bus and performs communication using Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA). The apparatus includes an edge detection section which detects an edge of data on the communication bus, and a data obtaining section which obtains data from the communication bus to determine a collision of data on the communication bus after a predetermined delay time period has passed from the time at which the edge detection section detects the edge.