Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes: a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting a resistive component between the pair of communication lines; and a reference potential provider configured to provide a reference potential, which corresponds to a midpoint potential of the pair of communication lines during a steady state, to an intermediate point of the resistive component.

Abstract: In a communication device, when an enabling signal is at a high level and a transmit data is at a high level, that is, in a recessive period, both transistors turn off. Thus, potentials of signal lines are determined by power supply from a second transmitting part to a communications network. When an error frame arises in this state, that is, transistors in the other ECU turn on, excessive currents flow the signal lines. When current monitoring circuits detect error currents, an error signal is changed to a high level.

Abstract: A ringing suppression circuit connected to a transmission line to suppress ringing caused by the transmission line transmitting a differential signal using a pair of signal lines, the differential signal varying between a high level and a low level, the pair of signal lines including a high potential signal line and a low potential signal line, the ringing suppression circuit including: an inter-line switching element that is connected between the pair of signal lines; a control portion that performs a ringing suppression operation in response to detecting a level change in the differential signal, wherein the ringing suppression operation turns on the inter-line switching element to decrease an impedance between the pair of signal lines; and a suppression operation prohibiting portion that prohibits the control portion from performing the ringing suppression operation in response to detecting a signal caused by a signal on the transmission line.

Abstract: A PoE power supply system includes a cable, a power supply device, a power reception device, and a request switch. The power supply device includes a power supply block and a power supply control block. The power supply block is configured to enable a connection state between the power supply device and the cable to be switched. The connection state includes a power supply state in which the power supply device is supplied with power required for operating the power supply device via the cable, and a standby state in which the power supply request signal is receivable by the power supply device via the cable. The power supply control block is configured to switch the connection state to the power supply state in response to receiving a power supply request signal output from the request switch and requesting the power supply device to resume supplying the power.

Abstract: A transmission circuit includes a first transmitter and a second transmitter. The first transmitter turns OFF first transistors when a transmission data is in a high level, and turns ON the first transistors when the transmission data is in a low level. When a permission signal is in the high level, the second transmitter turns ON the second transistors when the transmission data is in the high level, and turns OFF the second transistors when the transmission data is in the low level. Diodes are set to suppress an amplitude of a differential signal in an ON time of the second transistors more than an amplitude of a differential signal in an ON time of the first transistors, to suppress ringing and radiation noise.

Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting an adjustment circuit between the pair of communication lines. The adjustment circuit includes a resistive component and a capacitive component connected in series.

Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes: a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting a resistive component between the pair of communication lines; and a reference potential provider configured to provide a reference potential, which corresponds to a midpoint potential of the pair of communication lines during a steady state, to an intermediate point of the resistive component.

Abstract: A communication system includes a transmission path and multiple nodes. At least one of the multiple nodes includes a second communication portion and a control portion in addition to a first communication portion. When the control portion performs a high speed communication, the control portion shifts the first communication portion included in each of the remaining multiple nodes to a sleep mode. The second communication portion performs a differential communication at a higher speed than the first communication portion using a differential signal. In the differential signal, a maximum of a potential difference between the pair of communication lines is equal to or less than a recessive threshold value, and a minimum of the potential difference between the pair of communication lines is a negative voltage value that has a polarity opposite to the recessive threshold value of the first communication portion.

Abstract: A communication node is connected to a transmission line which transmits a differential signal changeable between a high level and a low level and has a high potential signal line and a low potential signal line as a pair of signal lines. The communication node includes: an inter-line potential detector that detects an intermediate potential between the pair of signal lines; a node potential detector that detects an intermediate potential of an operation power source voltage which is supplied to the communication node; and a voltage adjuster that detects a difference between the intermediate potential detected by the inter-line potential detector and the intermediate potential detected by the node potential detector, and adjusts the operation power source voltage in accordance with the difference.

Abstract: A communication load determining apparatus is used for a communication system which includes a plurality of communication devices performing communication via a common bus. The communication system operates in accordance with a communication protocol that defines which a priority order is set to each of the frames transmitted from the communication devices and which a frame having a lower priority has a longer transmission latency before being transmitted to the bus. In the communication load determining apparatus, a low-priority frame having a lower priority than other frames to the bus is transmitted, and a transmission latency of the low-priority frame is measured. The communication load determining apparatus determines whether or not abnormality has occurred in a communication load in the bus on the basis of the measured transmission latency to produce a determination result. The produced determination result is stored.

Abstract: A ringing suppression circuit, which is connected to a transmission line for transmitting a differential signal changeable between a high level and a low level in a binary level through a pair of a high potential side signal line and a low potential side signal line, and suppresses ringing that occurs in association with transmission of the differential signal, includes: an inter-line switching element that is connected to the pair of the high potential side signal line and the low potential side signal line; and a control unit that turns on the inter-line switching element and fixes an on state when detecting that the differential signal changes from the high level to the low level, and releases the on state after a predetermined time is measured and elapsed.

Abstract: A ringing suppression circuit, which is connected to a transmission line for transmitting a differential signal changeable between a high level and a low level in a binary level through a pair of a high potential side signal line and a low potential side signal line, and suppresses ringing that occurs in association with transmission of the differential signal, includes: an inter-line switching element that is connected to the pair of the high potential side signal line and the low potential side signal line; and a control unit that turns on the inter-line switching element and fixes an on state when detecting that the differential signal changes from the high level to the low level, and releases the on state after a predetermined time is measured and elapsed.

Abstract: A ringing suppression circuit includes: a single line switching element, which is driven by a voltage, that is connected between a pair of signal lines; a controller that detects a change in a level of the differential signal and turns on the single line switching element to lower an impedance between the pair of signal lines; a period detector that detects a length of a suppressing period indicated by a setting signal, which is an input; and a suppressing period storage that stores the length of the suppressing period which is detected by the period detector. In addition, the pair of signal lines includes a high potential signal line and a low potential signal line. Moreover, the controller turns on the single line switching element for only the suppressing period having the length, which is stored in the suppressing period storage.

Abstract: A ringing suppression circuit includes: a single line switching element, which is driven by a voltage, that is connected between a pair of signal lines; a controller that detects a change in a level of the differential signal and turns on the single line switching element to lower an impedance between the pair of signal lines; a period detector that detects a length of a suppressing period indicated by a setting signal, which is an input; and a suppressing period storage that stores the length of the suppressing period which is detected by the period detector. In addition, the pair of signal lines includes a high potential signal line and a low potential signal line. Moreover, the controller turns on the single line switching element for only the suppressing period having the length, which is stored in the suppressing period storage.

Abstract: A communication system includes a transmission path and multiple nodes. At least one of the multiple nodes includes a second communication portion and a control portion in addition to a first communication portion. When the control portion performs a high speed communication, the control portion shifts the first communication portion included in each of the remaining multiple nodes to a sleep mode. The second communication portion performs a differential communication at a higher speed than the first communication portion using a differential signal. In the differential signal, a maximum of a potential difference between the pair of communication lines is equal to or less than a recessive threshold value, and a minimum of the potential difference between the pair of communication lines is a negative voltage value that has a polarity opposite to the recessive threshold value of the first communication portion.

Abstract: A differential communication circuit includes: a first switch in between a signal line and a power source, a second switch in between a signal line and a ground, a third switch in between the signal line and the ground, a fourth switch in between the signal line and the power source, first and second drivers respectively driving the first and second switches, and third and fourth drivers respectively driving the third and fourth switches OFF to ON at an ON to OFF timing of the first and second switches, for setting an ON period of the third and fourth switches to be shorter than a one-bit width in a communication signal and enabling a stable signal level determination while reducing power consumption of the differential communication circuit.

Abstract: A communication node is connected to a transmission line which transmits a differential signal changeable between a high level and a low level and has a high potential signal line and a low potential signal line as a pair of signal lines. The communication node includes: an inter-line potential detector that detects an intermediate potential between the pair of signal lines; a node potential detector that detects an intermediate potential of an operation power source voltage which is supplied to the communication node; and a voltage adjuster that detects a difference between the intermediate potential detected by the inter-line potential detector and the intermediate potential detected by the node potential detector, and adjusts the operation power source voltage in accordance with the difference.

Abstract: In a communication device, when an enabling signal is at a high level and a transmit data is at a high level, that is, in a recessive period, both transistors turn off and both transistors turn off. Thus, potentials of signal lines are determined by power supply from a second transmitting part to a communications network. When an error frame arises in this state, that is, transistors in the other ECU turn on, excessive currents flow the signal lines. When current monitoring circuits detect error currents, an error signal is changed to a high level.

Abstract: A transmission circuit includes a first transmitter and a second transmitter. The first transmitter turns OFF first transistors when a transmission data is in a high level, and turns ON the first transistors when the transmission data is in a low level. When a permission signal is in the high level, the second transmitter turns ON the second transistors when the transmission data is in the high level, and turns OFF the second transistors when the transmission data is in the low level. Diodes are set to suppress an amplitude of a differential signal in an ON time of the second transistors more than an amplitude of a differential signal in an ON time of the first transistors, to suppress ringing and radiation noise.

Abstract: A differential communication circuit includes: a first switch in between a signal line and a power source, a second switch in between a signal line and a ground, a third switch in between the signal line and the ground, a fourth switch in between the signal line and the power source, first and second drivers respectively driving the first and second switches, and third and fourth drivers respectively driving the third and fourth switches OFF to ON at an ON to OFF timing of the first and second switches, for setting an ON period of the third and fourth switches to be shorter than a one-bit width in a communication signal and enabling a stable signal level determination while reducing power consumption of the differential communication circuit.