Control system for a bus system having at least two transmission lines

Abstract

The present invention relates to a control system for use in a bus system having at least two transmission lines, having a first control device which has a first termination path and a first terminating resistor connected to the first termination path, a second control device which has a second termination path and a second terminating resistor connected to the second termination path, a first connector which is adapted to connect the first control device to the transmission lines and therefore to integrate the first control device in the bus system, a second connector which is adapted to connect the second control device to the transmission lines and therefore to integrate the second control device in the bus system, wherein the first connector and the second connector are different to one another. The invention also relates to a connector for connecting a control device to transmission lines of a bus system. Finally, the invention also relates to a method for configuring a bus system having at least two transmission lines.

Claims

1: A control system for a bus system having at least two transmission lines, wherein the control system comprises: a first control unit which has a first termination path and a first terminating resistor connected to the first termination path; a second control unit which has a second termination path and a second terminating resistor connected to the second termination path; a first connector which is configured to connect the first control unit to the transmission lines and thus integrate the first control unit into the bus system; a second connector which is configured to connect the second control unit to the transmission lines and thus integrate the second control unit into the bus system; wherein the first connector and the second connector are designed differently from one another.

2: The control system as claimed in claim 1, wherein the first connector differs from the second connector at least in respect of a line bridge in the first connector which is configured to connect the first termination path to at least one transmission line and thus integrate the first terminating resistor of the first control unit into the bus system.

3: The control system as claimed in claim 1, wherein the first connector differs structurally from the second connector exclusively in respect of a line bridge in the first connector which is configured to connect the first termination path to at least one transmission line and thus integrate the first terminating resistor of the first control unit into the bus system.

4: The control system as claimed in claim 3, wherein the line bridge is configured to be detachably insertable into the first connector.

5: The control system as claimed in claim 4, wherein the line bridge in the inserted state is configured to establish a permanent, non-switchable connection between the first termination path and a transmission line.

6: The control system as claimed in claim 5, wherein precisely one termination path having precisely one terminating resistor is provided in the first control unit.

7: The control system as claimed in claim 5, wherein at at least two termination paths are provided in the first control unit and are provided in each case with a terminating resistor, and the termination path which is integrated into the bus system is selectable by the connector.

8: The control system as claimed in claim 7, wherein at at least two first connectors are configured so that they in each case integrate a terminating resistor via the respective termination path of the respectively contacted control unit into the bus system, and at least a second connector is designed and configured so that the terminating resistor provided in the respectively contacted control unit is not integrated into the bus system.

9: A connector configured to connect a control unit to transmission lines of a bus system, wherein the connector comprises: a control unit side interface which is adapted to accommodate a first data transmission path, a second data transmission path and a termination path; and a bus side interface which is adapted to connect the first path to a first transmission line and the second path to a second transmission line; wherein the bus side interface has a chamber into which a line bridge is insertable in order to connect the termination path to at least one transmission line.

10: The connector as claimed in claim 9, wherein the line bridge is inserted into the chamber.

11: A method for configuring a bus system having at least two transmission lines comprising: connecting a first control unit having a first termination path and a first terminating resistor connected thereto to a first connector which connects the first control unit to at least one transmission line; connecting a second control unit having a second termination path and a second terminating resistor connected thereto to a second connector which connects the second control unit to at least one transmission line; inserting a line bridge into at least one of: the first connector so that an operative connection is established between the first termination path and at least one transmission line and the first terminating resistor is therefore integrated into the bus system, and the second connector so that an operative connection is established between the second termination path and at least one transmission line and the second terminating resistor is therefore integrated into the bus system.

12: The method as claimed in claim 11, wherein the insertion of the line bridge into the first or the second connector is reversible.

13: The method as claimed in claim 11, wherein the line bridge in the inserted state establishes a permanent, non-switchable connection between the respective termination path and at least one transmission line.

14: The control system as claimed in claim 5, wherein precisely one termination path having precisely one terminating resistor is provided in the second control unit.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0056] Preferred further embodiments of the invention will be explained in detail by means of the following description of the figures. In the figures:

[0057] FIG. 1 shows a schematic view of a CAN bus system in general form;

[0058] FIG. 2 shows a schematic view of a control system having a first control unit and a second control unit according to one embodiment;

[0059] FIG. 3 shows a schematic view of a control system having a first control unit and a second control unit according to a further embodiment; and

[0060] FIG. 4 shows a schematic view of a further control unit.

DETAILED DESCRIPTION OF PREFERRED EXAMPLE EMBODIMENTS

[0061] Preferred example embodiments are described below with reference to the figures. Identical, similar or similarly acting elements are denoted with identical reference signs in the different figures and a description of these elements is in some instances not repeated in order to avoid duplication.

[0062] The design of a control system for a bus system having two transmission lines to be terminated, i.e. having two transmission lines to be provided with a terminating resistor, is presented schematically below on the basis of a CAN bus system. The CAN bus system is also representative here of other bus systems in which at least two transmission lines have to be terminated and in which a plurality of control units communicate with one another via the common transmission line.

[0063] FIG. 1 correspondingly represents the basic design of a CAN bus system 3. A control system 1 for use in a CAN bus system 3 having at least two transmission lines 2a, 2b will be explained in detail with reference to FIGS. 2 to 4. The CAN bus system 3 will first be described in its general form with reference to FIG. 1.

[0064] The CAN bus system 3 has a first transmission line 2a and a second transmission line 2b. The first transmission line 2a can be referred to as a CAN high line. The second transmission line 2b can be referred to as a CAN low line.

[0065] In an idle state, also referred to as a recessive state, the same voltage is present on both transmission lines 2a, 2b. This voltage can be, for example, 2.5 V. As soon as a signal is to be transmitted via the transmission lines 2a, 2b, i.e. the latter switch to a dominant state, the voltage on the CAN high line 2a increases, for example by 1 V. The voltage similarly decreases in the dominant state on the CAN low line 2b, for example similarly by 1 V. The voltage difference between the CAN high line 2a and the CAN low line 2b is therefore 0 V in the recessive state and, by way of example, 2 V in the dominant state, whereby a data transmission is enabled.

[0066] In order to inhibit reflections occurring in the CAN bus system 3 which can cause interference and therefore signal faults, two terminating resistors 102, 103, are generally to be arranged on opposite ends of the CAN bus system 3 to terminate the CAN bus system 3 and therefore instigate a targeted power dissipation on the respective terminating resistor 102, 103. The two terminating resistors in each case produce a resistance of 120 ohms for a total impedance of, for example, 60 ohms in the CAN bus system.

[0067] The CAN bus system 3 from FIG. 1 has a main control unit 101 which contains the terminating resistor 103. It similarly has any number of further control units 100 which are all connected to the transmission lines 2a, 2b. These control units 100 can be responsible, for example, for a battery control, a vehicle circuit, an airbag or other electronically controllable components. These control units 100 can be divided into a group of non-terminated control units 104 on the one hand, and into a terminating control unit 105 on the other hand. Whereas the non-terminated control units 104 implement no termination, i.e. they integrate no terminating resistor into the system, the terminated control unit 105 can implement a termination. The terminating resistor 102 is arranged in the terminated control unit 105 for this purpose.

[0068] FIG. 2 shows schematically a control system 1. This has a first control unit 4. A first termination path 5 is arranged in the first control unit 4. This can be accessible from outside the first control unit 4. A first terminating resistor 6 is further arranged in the first control unit 4. The first terminating resistor 6 is connected on one side to the first termination path 5 and on the other side to a first data transmission connection 13 of the control unit 4. The arrangement from FIG. 2 is shown merely by way of example. The terminating resistor 6 can similarly be arranged between the termination path 5 and a second data transmission connection 14 of the control unit 4.

[0069] The first data transmission connection 13 and the second data transmission connection 14 in each case represent electrical lines which are prepared for connection via a first connector 10 to the transmission lines 2a, 2b of the CAN bus system 3. The data transmission connections 13, 14 are typically combined on their open end in a socket which is designed as complementary to the connector 10 so that these internal data transmission connections 13, 14 of the control unit can be connected to the transmission lines 2a, 2b of the CAN bus system 3.

[0070] The first connector 10 therefore couples the first control unit 4 to the transmission lines 2a, 2b of the CAN bus system 3. A line bridge 12 is inserted into the first connector 10. A chamber provided correspondingly for the line bridge 12 can be arranged in the first connector 10 for this purpose. The line bridge 12 can be provided here in the form of a line splice which is arranged on its one end in the chamber in the connector 10 and its other end is either also spliced directly to the transmission line 2b inside the chamber of the connector 10 or this connection is established outside the connector. The line bridge 12 establishes an electrical connection between the second data transmission connection 14 and the first termination path 5. In this way, a voltage present in the second data transmission connection 14 drops via the first terminating resistor 6, as a result of which the first terminating resistor 6 is integrated into the CAN bus system 3. The first terminating resistor 6 therefore maintains the total impedance of, for example, 60 ohms in the CAN bus system 3.

[0071] Along with the first control unit 4, the control system 4 can have a second control unit 7. The design of the second control unit 7 is essentially similar to that of the first control unit 4. In one embodiment, the first control unit 4 and the second control unit 7 can also be identical. A second terminating resistor 9 is therefore arranged inside the second control unit 7. A second termination path 8 which is provided for connection to a second connector 11 is similarly arranged in the second control system 7. A third data transmission connection 15 and a fourth data transmission connection 16 provide an electrical connection of the second control unit 7 into the CAN bus system 3.

[0072] Here, similar to the first control unit 4, the second terminating resistor 9 is arranged between a second termination path 8 and the third termination path 15. No line bridge 12 is arranged in the connector 11 coupled to the second control unit 7, as a result of which the fourth data transmission connection 16 has no electrical connection to the second termination path 8. The second terminating resistor 9 is consequently not activated. The first connector 10 differs from the second connector 11 in respect of the arrangement of the line bridge 12. A termination of the CAN bus system 3 is consequently achieved by the different connector arrangement on a preferably identical control unit 4, 7.

[0073] The control units 4, 7 from FIG. 2 which are preferably identical to one another at least in respect of the design of the termination resistors in each case have two data transmission connections 13, 14, 15, 16. Each data transmission connection is connected to an electrical component which is represented here abstractly as a capacitor. The control units 4, 7 in each case further have a termination path 5, 8. In this embodiment, the first connector 10 therefore accommodates three paths 5, 13, 14 in total on a side facing toward the first control unit 4. The second connector 11 in this embodiment similarly accommodates three paths 8, 15, 16 on a side facing toward the second control unit 7. High flexibility is therefore achievable via a small number of paths.

[0074] FIG. 3 shows a second embodiment of the control system 1, having the first control unit 4 and the second control unit 7. As in the embodiment previously described in connection with FIG. 2, these control units are designed, for example, as structurally identical to one another. The first connector 10 is arranged on the first control unit 4, the second connector 11 on the second control unit 7. The first control unit 4 has the first termination path 5, the first terminating resistor 6, the first data transmission connection 13 and the second data transmission connection 14. Similarly, the second control unit 7 has the second termination path 8, the second terminating resistor 9, the third data transmission connection 15 and the fourth data transmission connection 16.

[0075] The first connector 10 has a line bridge 12 which, in the present example, connects the second data transmission connection 14 to the first termination path 5 so that the first terminating resistor 6 arranged in the first control unit 4 is integrated as a terminating resistor into the CAN bus system via the line bridge 12. The basic mode of operation of the control system 1 from FIG. 3 is similar to that shown in FIG. 2. The arrangement of the first terminating resistor 6 between the first termination path 8 and the first data transmission connection 13 is shown by way of example. It could similarly be arranged between the first termination path 8 and the second data transmission connection 14. This consideration is applicable to the arrangement of the second terminating resistor 9 in the second control system 7.

[0076] The individual data transmission connections of the control units from the embodiment according to FIG. 3 are similar in respect of their basic function to those of the embodiment according to FIG. 2. In respect of their structural design, the individual data transmission connections are provided in each case with two connections. Both control units 4, 7 in each case therefore have a termination connection 17 and a data transmission connection 18 for coupling to the connector 10, 11. The termination connection 17 is composed of paths which are prepared in order to be accommodated by the connector 10, 11 in order to provide a termination in this way—depending on the connector that is used. The data transmission connection 18 is composed of paths which are prepared in order to set up a connection to the transmission lines 2a, 2b via the connector 10, 11. The actual coupling between the transmission lines 2a, 2b and the respective control unit 4, 7 is therefore established via the transmission line connection 18.

[0077] An electrical connection is established between the first termination line 5 and the second data transmission connection 14 via the insertion of the line bridge 12 into the first connector 10, as a result of which the first terminating resistor 6 is integrated as a termination into the CAN bus system. In this way, the chamber on the first connector 10 which is prepared in order to accommodate the line bridge 12 is structurally separated from the interface between the transmission lines 2a, 2b and the first control unit 4 or the first connector 10, thus increasing operational reliability. A separation of the individual functions i.e. the functions of transmission to the CAN bus system and integration of the terminating resistor is similarly achieved in this way. This increases certainty and reduces susceptibility to error during assembly.

[0078] FIG. 4 shows the concept according to the invention in a further environment. Reference sign 19 denotes a control unit here by way of example in the form of a vehicle interface controller. The transmission lines 2a, 2b are coupled to the vehicle interface controller 19 via an external connector 21. An internal connector 22 is then arranged in order to establish a connection to an internal printed circuit board 20. The external connector 21 and the internal connector 22 can be similar in respect of their structural design to the first connector 10 and the second connector 11.

[0079] The pin assignment, i.e. the configuration of the individual pins, can differ here for the internal connector 22 and the external connector 21. Electrical lines of the printed circuit board 20 or the vehicle interface box 19 are connected to the CAN bus system 3 during the pin assignment through targeted insertion of the pins. The termination path 5 which is in turn operatively coupled to the first terminating resistor 6 is arranged on the printed circuit board 20. The line bridge 12 is inserted into the first connector 10 outside the vehicle interface controller 19 in order to integrate the first terminating resistor 6 into the CAN bus system 3. The present embodiment shows the variable usability of the connectors according to this disclosure which implement a flexibly adaptable termination of the CAN bus system 3 by means of the line bridge 12.

[0080] Insofar as applicable, all individual features which are shown in the example embodiments can be combined and/or exchanged with one another without departing the scope of the invention.

REFERENCE NUMBER LIST

[0081] 1 Control system

[0082] 2a,b Transmission line

[0083] 3 CAN bus system

[0084] 4 First control unit

[0085] 5 First termination path

[0086] 6 First terminating resistor

[0087] 7 Second control unit

[0088] 8 Second termination path

[0089] 9 Second terminating resistor

[0090] 10 First connector

[0091] 11 Second connector

[0092] 12 Line bridge

[0093] 13 First data transmission connection

[0094] 14 Second data transmission connection

[0095] 15 Third data transmission connection

[0096] 16 Fourth data transmission connection

[0097] 17 Termination connection

[0098] 18 Data transmission connection

[0099] 19 Vehicle interface controller

[0100] 20 Printed circuit board

[0101] 21 External connector

[0102] 22 Internal connector