CN207965556U - A kind of interference rejection ability is strong and has the CAN interface circuit of buffer action - Google Patents

Abstract

Strong and with buffer action the CAN interface circuit the utility model discloses a kind of interference rejection ability, including CAN chips U1, resistance R1, capacitance C2, capacitance C1, capacitance C4, capacitance C3, capacitance C5, capacitance C6, capacitance C7, common mode inductance L1, resistance R2, capacitance C8, capacitance C9, resistance R5, capacitance C11, TVS pipe D1, the left end of resistance R4, the upper end of capacitance C12, TVS pipe D1 and RC circuit, 3 pins of the RC circuits connect PTCAN_H pins, 4 pins of the RC circuits connect PTCAN_L pins, the right end of the resistance R4 is separately connected the left end of the right end and capacitance C10 of resistance R5.The beneficial effects of the utility model：CAN interface circuit provided by the utility model, it is strong with interference rejection ability, it can effectively inhibit different types of electromagnetic interference by the device of different parameters, CAN chips itself have buffer action simultaneously, the interference that power supply introduces can effectively be controlled, the interference free performance that CAN communication can be improved ensures the stability and reliability of circuit.

Description

A kind of interference rejection ability is strong and has the CAN interface circuit of buffer action

Technical field

The utility model is related to interface circuit technical fields, it particularly relates to which a kind of interference rejection ability is strong and with isolation The CAN interface circuit of effect.

Background technology

Battery management system is responsible for the energy stores transmission control of automobile as one of New-energy electric vehicle critical piece System, affects the performance of electric vehicle, service life and safety.Especially battery management system controls the complicated of power battery and fills Discharge process is responsible for the detection to the various abnormalities of power battery and reply processing, safe for guarantee power battery, Effec-tive Function plays decisive role.

Battery management system is in the complex electromagnetic environment of electric vehicle, especially the high interferences such as driving motor, DCDC Equipment battery management system can all be impacted, CAN communication module is responsible for the communication of battery management system, once CAN logical Letter module receives extraneous interference, can seriously affect the function of battery management system, or even cause vehicle trouble.Therefore, it is promoted The anti-interference ability of CAN communication module is also highly important.

Utility model content

For above-mentioned technical problem in the related technology, the utility model proposes a kind of interference rejection abilities by force and with isolation work CAN interface circuit can overcome the above-mentioned deficiency of the prior art.

To realize the above-mentioned technical purpose, the technical solution of the utility model is realized in：

A kind of interference rejection ability is strong and has the CAN interface circuit of buffer action, including CAN chips U1, the CAN chips U1 4 pins connect M_CAN1_RX pins, 5 pins of the CAN chips U1 are separately connected M_CAN1_TX pins and resistance R1 The upper end of lower end, the resistance R1 connects 3.3V pins, and 6 pins of the CAN chips U1 are separately connected the upper end of capacitance C2, electricity Hold upper end and the 3.3V pins of C1,8 pins of the CAN chips U1 be separately connected the upper end of capacitance C4, capacitance C3 upper end and+ 5V pins, 12 pins of the CAN chips U1 are separately connected the upper end of capacitance C5, the upper end of capacitance C6 and CAN_ISO_POW and draw Foot, the upper end of the 14 pins connection capacitance C7 of the CAN chips U1, the 15 pins connection common mode inductance L1 of the CAN chips U1 2 pins, 1 pin of the 17 pins connection common mode inductance L1 of the CAN chips U1, the 18 pins connection of the CAN chips U1 19 pins of the lower end of resistance R2, the CAN chips U1 are separately connected the lower end of capacitance C8, the lower end of capacitance C9 and CAN_ISO_ POW pins, 3 pins of the common mode inductance L1 are separately connected the left end of resistance R5, the lower end of capacitance C11, TVS pipe D1 1 draw 4 pins of 1 pin of foot and RC circuits, the common mode inductance L1 are separately connected the left end of resistance R4, the upper end of capacitance C12, TVS 3 pins of 2 pins of pipe D1 and 2 pins of RC circuits, the RC circuits connect PTCAN_H pins, 4 pins of the RC circuits PTCAN_L pins are connected, the right end of the resistance R4 is separately connected the left end of the right end and capacitance C10 of resistance R5, the CAN cores The 10 of 1 pin of piece U1,3 pins of CAN chips U1,7 pins of CAN chips U1,9 pins of CAN chips U1, CAN chips U1 Pin, the lower end of capacitance C1, the lower end of capacitance C2, the lower end of capacitance C3 and capacitance C4 lower end connect DGND pins, the electricity Hold the lower end of C5, the lower end of capacitance C6,11 pins of CAN chips U1, CAN chips U1 13 pins, the lower end of capacitance C7, CAN 16 pins of chip U1,20 pins of CAN chips U1, the upper end of capacitance C8, the upper end of capacitance C9, the upper end of resistance R2, capacitance The right end of C10, the upper end of capacitance C11, the lower end of capacitance C12 and TVS pipe D1 3 pins be all connected with CAN_GND pins.

Further, the RC circuits include capacitance C12, and the upper end of the capacitance C13 is separately connected the left end of resistance R3 PTCAN is connected with the right end of 2 pins of TVS pipe D1, the resistance R3_—The lower end of H pins, the capacitance C13 is separately connected electricity 1 pin of the left end and TVS pipe D1 of R6 is hindered, the right end of the resistance R6 connects PTCAN_—L pins.

The beneficial effects of the utility model：CAN interface circuit provided by the utility model has interference rejection ability strong, passes through The device of different parameters can effectively inhibit different types of electromagnetic interference, while CAN chips itself have buffer action, can be effective The interference that control power supply introduces, can improve the interference free performance of CAN communication, ensure the stability and reliability of circuit.

Description of the drawings

In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Needed in attached drawing be briefly described, it should be apparent that, the accompanying drawings in the following description is only the utility model Some embodiments for those of ordinary skill in the art without creative efforts, can also be according to this A little attached drawings obtain other attached drawings.

Fig. 1 is that a kind of interference rejection ability according to the utility model embodiment is strong and CAN interface with buffer action The circuit diagram of circuit.

Specific implementation mode

The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model Clearly and completely describe, it is clear that the described embodiments are only a part of the embodiments of the utility model, rather than whole Embodiment.Based on the embodiments of the present invention, the every other embodiment that those of ordinary skill in the art are obtained all belongs to In the range of the utility model protection.

As shown in Figure 1, a kind of interference rejection ability according to the utility model embodiment is strong and has the CAN of buffer action Interface circuit, include CAN chips U1, the CAN chips U1 4 pins connect M_CAN1_RX pins, the 5 of the CAN chips U1 Pin is separately connected the lower end of M_CAN1_TX pins and resistance R1, and the upper end of the resistance R1 connects 3.3V pins, the CAN 6 pins of chip U1 are separately connected the upper end of capacitance C2, the upper end of capacitance C1 and 3.3V pins, 8 pins of the CAN chips U1 It is separately connected the upper end of capacitance C4, the upper end of capacitance C3 and+5V pins, 12 pins of the CAN chips U1 are separately connected capacitance The upper end of C5, the upper end of capacitance C6 and CAN_ISO_POW pins, the upper end of the 14 pins connection capacitance C7 of the CAN chips U1, 2 pins of the 15 pins connection common mode inductance L1 of the CAN chips U1,17 pins of the CAN chips U1 connect common mode inductance 1 pin of L1, the lower end of the 18 pins connection resistance R2 of the CAN chips U1,19 pins of the CAN chips U1 are separately connected The lower end of capacitance C8, the lower end of capacitance C9 and CAN_ISO_POW pins, 3 pins of the common mode inductance L1 are separately connected resistance The left end of R5, the lower end of capacitance C11,1 pin of TVS pipe D1 and RC circuits 1 pin, 4 pins of the common mode inductance L1 point Not Lian Jie the left end of resistance R4, the upper end of capacitance C12,2 pins of TVS pipe D1 and RC circuits 2 pins, the 3 of the RC circuits Pin connects PTCAN_H pins, and 4 pins of the RC circuits connect PTCAN_L pins, and the right end of the resistance R4 is separately connected The left end of the right end and capacitance C10 of resistance R5,1 pin of the CAN chips U1,3 pins of CAN chips U1, CAN chips U1 Under 7 pins, 9 pins of CAN chips U1,10 pins of CAN chips U1, the lower end of capacitance C1, the lower end of capacitance C2, capacitance C3 End and the lower end of capacitance C4 connect DGND pins, the lower end of the capacitance C5, the lower end of capacitance C6, CAN chips U1 11 pins, 13 pins of CAN chips U1, the lower end of capacitance C7,16 pins of CAN chips U1,20 pins of CAN chips U1, capacitance C8 it is upper End, the upper end of capacitance C9, the upper end of resistance R2, the right end of capacitance C10, the upper end of capacitance C11, the lower end of capacitance C12 and TVS pipe 3 pins of D1 are all connected with CAN_GND pins.

In one embodiment, the RC circuits include capacitance C12, and the upper end of the capacitance C13 is separately connected resistance The right end of the left end of R3 and 2 pins of TVS pipe D1, the resistance R3 connects PTCAN_—H pins, the lower end point of the capacitance C13 Not Lian Jie the left end of resistance R6 and 1 pin of TVS pipe D1, the right end of the resistance R6 connects PTCAN_—L pins.

In order to facilitate the above-mentioned technical proposal of the utility model is understood, below by way of new to this practicality in specifically used mode The above-mentioned technical proposal of type is described in detail.

When specifically used, the utility model includes CAN chips, common mode inductance, X capacitances, Y capacitance, TVS pipe, RC circuits； Wherein, common mode inductance L1, Y capacitance include capacitance C1, capacitance C2, capacitance C3, capacitance C4, capacitance C5, capacitance C6, capacitance C7, electricity Hold the common mode that C8, capacitance C9, capacitance C10, capacitance C11 and capacitance C12, common mode inductance L1 and Y capacitance mainly inhibit interface circuit Interference, X capacitances C13 mainly inhibits the DM EMI between CANH and CANL, while C13 forms RC circuits with R3, R6, to TVS Pipe D1 is protected, and TVS pipe D1 can effectively inhibit the glitch of interface circuit.

The utility model also has transient state inhibition, em filtering and TVS defencive functions.

In conclusion CAN interface circuit provided by the utility model, has interference rejection ability strong, passes through the device of different parameters Part can effectively inhibit different types of electromagnetic interference, while CAN chips itself have buffer action, can effectively control power supply and introduce Interference, the interference free performance of CAN communication can be improved, ensure the stability and reliability of circuit.

The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this Within the spirit and principle of utility model, any modification, equivalent replacement, improvement and so on should be included in the utility model Protection domain within.

Claims (2)

1. a kind of interference rejection ability is strong and has the CAN interface circuit of buffer action, which is characterized in that described including CAN chips U1 4 pins of CAN chips U1 connect M_CAN1_RX pins, 5 pins of the CAN chips U1 be separately connected M_CAN1_TX pins and The upper end of the lower end of resistance R1, the resistance R1 connects 3.3V pins, and 6 pins of the CAN chips U1 are separately connected capacitance C2 Upper end, capacitance C1 upper end and 3.3V pins, 8 pins of the CAN chips U1 be separately connected the upper end of capacitance C4, capacitance C3 Upper end and+5V pins, 12 pins of the CAN chips U1 are separately connected the upper end of capacitance C5, the upper end of capacitance C6 and CAN_ ISO_POW pins, the upper end of the 14 pins connection capacitance C7 of the CAN chips U1, the 15 pins connection of the CAN chips U1 is altogether 2 pins of mould inductance L1,1 pin of the 17 pins connection common mode inductance L1 of the CAN chips U1, the 18 of the CAN chips U1 Pin connects the lower end of resistance R2,19 pins of the CAN chips U1 be separately connected the lower end of capacitance C8, capacitance C9 lower end and 3 pins of CAN_ISO_POW pins, the common mode inductance L1 are separately connected the left end of resistance R5, the lower end of capacitance C11, TVS pipe 1 pin of D1 and 1 pin of RC circuits, 4 pins of the common mode inductance L1 are separately connected the left end of resistance R4, capacitance C12 Upper end, 2 pins of TVS pipe D1 and RC circuits 2 pins, 3 pins of the RC circuits connect PTCAN_H pins, the RC electricity 4 pins on road connect PTCAN_L pins, and the right end of the resistance R4 is separately connected the left end of the right end and capacitance C10 of resistance R5, 1 pin of the CAN chips U1,9 pins, the CAN cores of 3 pins of CAN chips U1,7 pins of CAN chips U1, CAN chips U1 10 pins of piece U1, the lower end of capacitance C1, the lower end of capacitance C2, the lower end of capacitance C3 and capacitance C4 lower end meet DGND and draw Foot, the lower end of the capacitance C5, the lower end of capacitance C6,11 pins of CAN chips U1,13 pins of CAN chips U1, capacitance C7 Lower end, 16 pins of CAN chips U1,20 pins of CAN chips U1, the upper end of capacitance C8, the upper end of capacitance C9, resistance R2 it is upper End, the right end of capacitance C10, the upper end of capacitance C11, the lower end of capacitance C12 and TVS pipe D1 3 pins be all connected with CAN_GND and draw Foot.

2. a kind of interference rejection ability according to claim 1 is strong and there is the CAN interface circuit of buffer action, feature to exist In the RC circuits include capacitance C12, and the upper end of the capacitance C13 is separately connected the left end of resistance R3 and the 2 of TVS pipe D1 are drawn The right end of foot, the resistance R3 connects PTCAN_—The lower end of H pins, the capacitance C13 is separately connected the left end and TVS of resistance R6 The right end of 1 pin of pipe D1, the resistance R6 connects PTCAN_—L pins.