Transceiver circuit for a controller area network with improved safety

Patent metadata

Field	Value
Publication number	US-10459863-B2
Application number	US-201715814645-A
Country	US
Kind code	B2
Filing date	Nov 16, 2017
Priority date	Nov 16, 2016
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

A transceiver circuit for communicating data over a CAN bus having a first and second bus line the transceiver circuit comprising: a data input port, a data output port, a CAN-bus transceiver unit having a receive data output port for providing data received from the CAN-bus, and a transmit data input port for receiving data to be transmitted to the CAN-bus; a control input port for receiving a control signal indicative of whether transmission of data from this transceiver circuit to the CAN-bus is allowed or prohibited; a filtering circuit adapted for filtering the control signal received on the control input port and for providing a filtered control signal; a logic circuitry adapted for configuring the CAN-bus transceiver unit in receive mode based on the debounced control signal irrespective of ongoing communication on the CAN-bus.

First claim

The invention claimed is:

1. A CAN-node comprising:
a transceiver circuit for communicating data over a CAN bus, the CAN-bus having at least a first and a second bus line, the circuit comprising:
a data input port for receiving a signal to be transmitted over the CAN-bus;
a data output port for providing a signal received from the CAN-bus;
a CAN-bus transceiver unit having a receive data output port for providing data received from the CAN-bus, and a transmit data input port for receiving data to be transmitted to the CAN-bus;
a control input port adapted for receiving a control signal indicative of whether transmission of data from this transceiver circuit to the CAN-bus is allowed or prohibited;
a filter circuit adapted for filtering the control signal received on the control input port and for providing a filtered control signal;
logic circuitry adapted for configuring the CAN-bus transceiver unit in receive mode based on the filtered control signal, asynchronous with respect to communication on the CAN-bus, thereby preventing the circuit from transmitting data to the CAN-bus; and

a controller adapted for generating data, and having an input port connected to the data output port of the transceiver circuit for receiving data from the CAN-bus, and having an output port connected to the data input port of the transceiver circuit for transmitting the generated data to the CAN-bus;
wherein the controller comprises:
a state machine for generating said data to be transmitted via said output port and for processing data received via said input port; and
a monitoring unit for monitoring the data transmitted by the state machine, and for providing a control signal for selectively allowing or preventing the generated data to be transmitted to the CAN-bus.

2. A CAN-node according to claim 1 , wherein the controller further comprises:
an enable port connected to the control input port of the transceiver circuit for selectively allowing or prohibiting transmission of data to the CAN-bus.

3. A CAN-node according to claim 1 , further comprising:
a second controller having an enable port connected to the control input port of the transceiver circuit, the second controller being adapted for monitoring the data transmitted by the first controller, and for providing a control signal for selectively allowing or preventing the generated data to be transmitted to the CAN-bus.

4. A CAN-bus system comprising:
a CAN-bus having at least a first and a second bus line;
at least one CAN-node according to claim 1 ,
wherein the at least one CAN node comprises a first CAN-node, the first CAN-node being connected to the CAN-bus, and comprising said controller for generating data, and comprising the transceiver circuit with the control input port;
and wherein the CAN-bus system further comprises a monitoring unit for monitoring the data transmitted by the first CAN node, and having an output port connected to the control input port of the first CAN-node, and adapted for monitoring the data and/or analysing the traffic transmitted by the first CAN-node, and adapted providing a control signal for selectively allowing or preventing the data generated by the controller of the first CAN-node to be transmitted to the CAN-bus.

5. The CAN-node according to claim 1 , wherein the filter circuit is a debouncing circuit.

6. The CAN-node according to claim 1 , wherein the logic circuitry is adapted for configuring the CAN-bus transceiver unit in receive mode solely based on the filtered control signal and/or on a signal present on the data input port.

7. The CAN-node according to claim 1 , wherein the output of the logic circuitry is directly connected to the transmit data input port of the CAN-bus transceiver unit.

8. The CAN-node according to claim 1 , wherein the logic circuitry does not contain an isolated switch.

9. The CAN-node according to claim 1 , wherein the logic circuitry consists only of combinatorial gates.

10. The CAN-node according to claim 1 , wherein the logic circuitry is adapted for operating asynchronously in respect to traffic over the CAN network.

11. A CAN-bus system comprising:
a CAN-bus having at least a first and a second bus line;
at least one CAN-node comprising:
a transceiver circuit for communicating data over the CAN bus, the circuit comprising:
a data input port for receiving a signal to be transmitted over the CAN-bus;
a data output port for providing a signal received from the CAN-bus;
a CAN-bus transceiver unit having a receive data output port for providing data received from the CAN-bus, and a transmit data input port for receiving data to be transmitted to the CAN-bus;
a control input port adapted for receiving a control signal indicative of whether transmission of data from this transceiver circuit to the CAN-bus is allowed or prohibited;
a filter circuit adapted for filtering the control signal received on the control input port and for providing a filtered control signal;
logic circuitry adapted for configuring the CAN-bus transceiver unit in receive mode based on the filtered control signal, asynchronous with respect to communication on the CAN-bus, thereby preventing the circuit from transmitting data to the CAN-bus; and

a controller adapted for generating data, and having an input port connected to the data output port of the transceiver circuit for receiving data from the CAN-bus, and having an output port connected to the data input port of the transceiver circuit for transmitting the generated data to the CAN-bus;

wherein the at least one CAN node comprises a first CAN-node, the first CAN-node being connected to the CAN-bus, and comprising said controller for generating data, and comprising the transceiver circuit with the control input port;
and wherein the CAN-bus system further comprises a monitoring unit for monitoring the data transmitted by the first CAN node, and having an output port connected to the control input port of the first CAN-node, and adapted for monitoring the data and/or analysing the traffic transmitted by the first CAN-node, and adapted providing a control signal for selectively allowing or preventing the data generated by the controller of the first CAN-node to be transmitted to the CAN-bus.

Assignees

• Melexis Technologies Nv

Inventors

• Sturm Joergen
• Freitag Thomas
• Frey Michael

Classifications

• B60R16/0315

  using multiplexing techniques (multiplexing for transmission of signals G08C15/00; multiplexing for electrical communication in general H04J) · CPC title

• H04L12/40013 Primary

  Details regarding a bus controller · CPC title

• H04L12/40032

  Details regarding a bus interface enhancer · CPC title

• H04L2012/4026

  Bus for use in automation systems · CPC title

• G05B19/0423

  Input/output · CPC title