CN203984448U

CN203984448U - A kind of CAN bus module of tape terminal resistance selection circuit

Info

Publication number: CN203984448U
Application number: CN201320890148.8U
Authority: CN
Inventors: 赵佳; 朱振林
Original assignee: Zhongtong Bus Holding Co Ltd
Current assignee: Zhongtong Bus Holding Co Ltd
Priority date: 2013-12-30
Filing date: 2013-12-30
Publication date: 2014-12-03
Anticipated expiration: 2023-12-30

Abstract

The CAN bus module that the utility model discloses a kind of tape terminal resistance selection circuit, comprises CAN bus transceiver, resistance and toggle switch, in parallel with CAN bus transceiver after resistance and toggle switch series connection.The utility model increases terminal resistance at the interface of the bus transceiver of module and selects circuit, terminal resistance selects circuit by terminal resistance and toggle switch, by changing the whether tape terminal resistance of condition selecting inside modules of toggle switch, in the time that module need to be placed in the two ends of bus network, closed toggle switch, module carries terminal resistance, without in addition on wire and connecting resistance; In the time that module does not need to be placed in the two ends of bus network, disconnect toggle switch, inside modules does not have terminal resistance, meets instructions for use.

Description

A kind of CAN bus module of tape terminal resistance selection circuit

Technical field

The utility model relates to a kind of CAN bus module of tape terminal resistance selection circuit.

Background technology

CAN bus be German BOSCH company 20th century the mid-80 be to solve a kind of communication and the control technology that the exchanges data between each electronic-controlled installation is developed, in recent years, paid much attention to because it has compared with high reliability and good fault-tolerant ability, be widely used in that temperature is severe, electromagnetic radiation is strong and vibrates large Environment of Automobile Industry.For eliminating the reflected wave of bus network generation, must respectively increase at the two ends of network the terminal resistance of 120 Ω, to strengthen signal strength signal intensity.Other position of network does not need to increase resistance.At present, terminal resistance has two kinds of modes of emplacements, and a kind of is to be independently attempted by the wire at two ends, networking, and troublesome poeration, aesthetic property is poor, reliability is low; Another kind is to be built in CAN bus module inside, causes module must be placed on the two ends at networking and can not be placed on other position, very flexible.

Utility model content

The utility model is in order to address the above problem, a kind of CAN bus module of tape terminal resistance selection circuit has been proposed, this module increases terminal resistance at the interface of bus transceiver and selects circuit, position according to module in bus network, the state of inside modules terminal resistance is set easily, simple to operate, flexibility and reliability.

To achieve these goals, the utility model adopts following technical scheme:

A kind of CAN bus module of tape terminal resistance selection circuit, comprise CAN bus transceiver, resistance and toggle switch, in parallel with CAN bus transceiver after resistance and toggle switch series connection, use altogether n CAN bus module, when use, described CAN bus module is connected into a CAN bus network, as required, bus module 1 and bus module n, n > 1, n is natural number, be arranged in the end positions of network, bus module 2 is arranged in the position between network two ends to bus module n-1.

The resistance of described resistance is 120 Europe.

Principle of the present utility model is: increase terminal resistance at the interface of the bus transceiver of module and select circuit, terminal resistance selects circuit by terminal resistance and toggle switch, by changing the whether tape terminal resistance of condition selecting inside modules of toggle switch, in the time that module need to be placed in the two ends of bus network, closed toggle switch, module carries terminal resistance, without in addition on wire and connecting resistance; In the time that module does not need to be placed in the two ends of bus network, disconnect toggle switch, inside modules does not have terminal resistance, meets instructions for use.

The beneficial effects of the utility model are:

The wire of CAN bus network does not need external terminal resistance, and the position according to module in bus network arranges the state of inside modules terminal resistance, simple to operate, flexibility and reliability easily.

Brief description of the drawings

Fig. 1 is structural representation of the present utility model;

Fig. 2 is preferred connection diagram of the present utility model.

Embodiment:

Below in conjunction with accompanying drawing and embodiment, the utility model is described in further detail.

As shown in Figure 1, a kind of CAN bus module of tape terminal resistance selection circuit, comprises CAN bus transceiver, resistance and toggle switch, in parallel with CAN bus transceiver after resistance and toggle switch series connection.

The resistance of resistance is 120 Europe.

Increase terminal resistance at the interface of the bus transceiver of module and select circuit, terminal resistance selects circuit by terminal resistance and toggle switch, by changing the whether tape terminal resistance of condition selecting inside modules of toggle switch, in the time that module need to be placed in the two ends of bus network, closed toggle switch, module carries terminal resistance, without in addition on wire and connecting resistance; In the time that module does not need to be placed in the two ends of bus network, disconnect toggle switch, inside modules does not have terminal resistance, meets instructions for use.

As shown in Figure 2, use altogether n CAN bus module, when use, CAN bus module described in the utility model is connected into a CAN bus network, as required, bus module 1 and bus module n (n > 1, n is natural number) be arranged in the end positions of network, bus module 2 is arranged in the position between network two ends to bus module n-1.The toggle switch K1 closure of bus module 1 and bus module n, bus module 2 is to the toggle switch K1 disconnection of bus module n-1.The each terminal resistance that forms 120 Ω of bus module 1 and bus module n, is responsible for absorbing and eliminates the reflected wave that bus network produces, and strengthens the intensity of CAN bus signals.

Toggle switch K1 is single-pole double-throw switch (SPDT), can be built in completely in CAN bus module, also can expose to outside CAN bus module.

By reference to the accompanying drawings embodiment of the present utility model is described although above-mentioned; but the not restriction to the utility model protection range; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various amendments that creative work can make or distortion still in protection range of the present utility model.

Claims

1. the CAN bus module of a tape terminal resistance selection circuit, it is characterized in that: comprise CAN bus transceiver, resistance and toggle switch, in parallel with CAN bus transceiver after resistance and toggle switch series connection, use altogether n CAN bus module, when use, described CAN bus module is connected into a CAN bus network, as required, bus module 1 and bus module n, n > 1, n is natural number, be arranged in the end positions of network, bus module 2 is arranged in the position between network two ends to bus module n-1.

2. the CAN bus module of a kind of tape terminal resistance selection circuit as claimed in claim 1, is characterized in that: the resistance of described resistance is 120 Europe.