CN202596414U

CN202596414U - Controller area network (CAN) bus-based electric controller for automobile windows

Info

Publication number: CN202596414U
Application number: CN2012201241092U
Authority: CN
Inventors: 侯红玲
Original assignee: Shaanxi University of Technology
Current assignee: Shaanxi University of Technology
Priority date: 2012-03-26
Filing date: 2012-03-26
Publication date: 2012-12-12
Anticipated expiration: 2022-03-26

Abstract

The utility model relates to a controller area network (CAN) bus-based electric controller for automobile windows. According to the controller, the lifting of glass of the four automobile windows is realized by software programming, and wiring harnesses in an automobile are reduced greatly on the premise of not changing the original network hardware structure. A CAN controller is integrated inside a PIC18F258 singlechip, and on-line programming can be performed, so that each function of the controller is realized well. A main controller can control the lifting of the glass of the automobile window of a driver and can also control the lifting of the other three automobile windows of passengers by a CAN bus; and a sub controller can also control the lifting of the glass of the automobile window at respective position. The electric controller, which is designed by a chip, for the automobile windows is stable in performance and reliable in operation.

Description

Automotive window electric controller based on the CAN bus

Technical field

The utility model belongs to a kind of AE field, relates to a kind of automotive window electric controller based on the CAN bus.

Background technology

Along with the development of automotive electronic technology, increasing electronic product is loaded on the automobile, has greatly improved the dynamic property and the comfortableness of automobile, has also increased the difficulty and the cost of wiring in the car simultaneously.CAN (Controller Area Network) as a kind of serial data communications busses, has good reliability, real-time and flexibility, in automobile electronic system, has obtained using widely.

The automotive window electric controller is as main safety component of automobile, and the sealing and the safety of vehicle body had direct influence, has influence on driver and conductor's driving environment on the one hand, even can threaten personal safety.In the automotive window design, utilize the CAN bussing technique can simplify the design of hardware circuit greatly, improved the reliability of automotive window electric controller.

At present; In the design of CAN system; Using maximum is the plug-in independent CAN controller of single-chip microcomputer, like 82526,82527 etc. of PCA82C200, SJA1000 and the Intel Company of Philips company, but adopts the design scheme of this type of chip to be unfavorable for system integration.Owing to only need TXD, two data wires of RXD when adopting the PIC18F258 single-chip microcomputer that CAN transceiver PCA82C250 is carried out data manipulation, so just simplified the design of hardware circuit greatly, and helped improving the reliability of controller.Therefore, the design will realize the electronic control of four vehicle windows of automobile with the PIC18F258 single-chip microcomputer as controller.

Summary of the invention

The utility model provides a kind of automotive window electric controller based on the CAN bus.Adopt the PIC18F258 single-chip microcomputer as controller, this single-chip microcomputer is inner integrated CAN controller can reduce the wire harness in the car; Utilize the online programming function of PIC18F258 single-chip microcomputer, under the prerequisite that does not change the legacy network hardware configuration, can realize the up-down of glass for vehicle window.

In order to realize above-mentioned task, the technical solution that the utility model adopts is following:

A kind of automotive window electric controller based on the CAN bus has four CAN Node Controllers, is respectively left front window motor master controller, right front window motor sub-controller, left back window motor sub-controller, right back window motor sub-controller; Four CAN Node Controllers are connected with the CAN bus respectively, realize the communication between four vehicle window controllers through the CAN bus; Operate left front window master controller except can controlling left front window glass up-down, also can communicate by letter with the motor sub-controller of its excess-three vehicle window, control institute to deserved lifting glass for vehicle window through sub-controller through the CAN bus; The hardware circuit of four CAN Node Controllers is made up of single-chip microcomputer, photoelectrical coupler, bus transceiver and power drive chip four parts.

The utility model also comprises following other technologies characteristic:

Said single-chip microcomputer is the PIC18F258 single-chip microcomputer;

Said photoelectrical coupler is the 6N137 high-speed photoelectric coupler;

Said bus transceiver is the PCA82C250 bus transceiver;

Said power drive chip adopts the power drive chip MC33486 of motorola inc.

Description of drawings

Fig. 1 is the system hardware structure figure of the utility model;

Fig. 2 is the initialization subroutine flow chart of the utility model;

Fig. 3 is the Electric Machine Control subroutine flow chart of the utility model.

The specific embodiment

The general requirement of the power vehicle window controller hardware circuit design of the utility model is simple, the realization, stable and reliable for performance easily of system, under situation about meeting the demands, minimizes cost.The hardware circuit of CAN Node Controller is made up of four parts: PIC18F258 single-chip microcomputer, 6N137 high-speed photoelectric coupler, PCA82C250 bus transceiver and power drive chip MC33486.PIC18F258 is the high-performance PIC series monolithic that the inside of U.S. Microchip company production is embedded with the CAN bus control unit, and owing to its microminiature, low-power consumption, low cost, many kinds, its range of application very extensively.PIC18F258 the has been integrated microcontroller of CAN module; Advanced reduced instruction set computer framework, enhancement mode kernel, 32 grades of storehouses are arranged; Have Flash program storage, EEROM data storage, programme function, in-circuit debugger (ICD) and multiple inside, exterior interrupt certainly in the sheet, and adopted program and data space distinct " Harvard " structure.This structure greatly reduces the overall cost of PIC microcontroller, has improved operational efficiency simultaneously.In circuit, the PIC18F258 single-chip microcomputer is the core of CAN bus interface circuit, mainly accomplishes the transmission and the reception of data on the CAN bus, realizes the decomposition and the combination of serial data, guarantees the normally unimpeded of communication.PCA82C250 is the CAN Bus Interface Chip of Philips company; Be the interface between CAN controller and the physical bus, the function that the difference of bus is sent and received is provided, it and IS011898 standard are compatible fully; Three kinds of different working modes are arranged; Promptly high speed, slope control and standby can be selected according to actual conditions, in this programme, select the high speed operation mode.This chip pin is few, uses simple.The CAN bus adopts the interface between PCA82C250 chip conduct and the bus, and the CANH of PCA82C250, CANL pin link to each other with the CAN bus through a resistance separately, and resistance can play certain metering function, and protection PCA82C250 avoids the impact of overcurrent.In addition, parallelly connected two little electric capacity between CANH and CANL and the ground, High-frequency Interference and anti-electromagnetic radiation on can the filtering bus.The high-speed logic gate output photoelectrical coupler 6N137 that photoelectrical coupler adopts General Instrument company to produce; Its maximum traffic delay time is 75ns; Representative value is 46ns; Adopt 6N137 high speed optoelectronic coupling circuit can realize the electrical isolation between the node on the bus well, can improve the ability of antijamming capability with the transmission signal of system simultaneously.During use, two the power supply VCC and the V ' CC of photoelectrical coupler must adopt power isolation circuit to isolate fully.

The application model of the power drive chip of the utility model is a bridge architecture; Chip internal has 2 high-end MOSFET driving tube MOS1, MOS2; External 2 low side MOSFET driving tube MOS3, MOS4 form a complete H bridge, realize the forward and reverse control of Car window electric machine.Simultaneously, the current-mirror function of utilizing Cur R to hold can realize the pinch resistant functionality of overcurrent protection and vehicle window easily.OUT1 and OUT2 are two high-end output pins of MC33486, directly drive Car window electric machine.IN1 and IN2 receive the control of microcontroller.When IN1 is a high level ' 1 ', when IN2 is a low level ' 0 ', corresponding GLS1 output low level, GLS2 export high level, MOS1, MOS4 conducting at this moment, MOS2, MOS3 end.OUT1 exports positive voltage and OUT2 ground connection, and Car window electric machine is towards some direction runnings.Otherwise, when IN1 is a low level ' 0 ', when IN2 is a high level ' 1 ', corresponding GLS2 output low level, GLS1 export high level, MOS2, MOS3 conducting at this moment, MOS1, MOS4 end.OUT2 just is output as, OUT1 ground connection, and Car window electric machine reverses, and reaches the purpose of lift truck window glass.In addition, MC33486 has low-down quiescent current under standby mode, and the output current when operate as normal is I0A, and peak inrush current is 35A, and wider range of DC input voitage can reach 8V～28V.Chip has over-voltage protecting function when voltage is higher than 28V.Because this device performance is perfect, thereby can reduce the volume of power vehicle window controller, improve EMS (electromagnetic compatibility) characteristic.

The system initialization subprogram of the utility model is a part and parcel very in system's design work, and it is the prerequisite of CAN bus system operate as normal, and can be related to whole C AN system operate as normal.Therefore, initialization design is an emphasis, mainly comprise configuration, the receiving filter of CAN module working method setting, receive mask register setting, the setting of baud rate parameter, send the priority setting and interrupt allowing register to be provided with etc.Control to power windows can be divided into soft start, full PWM output, afterflow and stop 4 stages.Comprising the judgement of power windows " manual " control and processing, vehicle window being risen to the top or dropping to judgement and the processing etc. of judgement and processing, the anti-pinching car window at the end.After program initialization was accomplished, after the control command that the input of rising or decline button is arranged, main program called the Electric Machine Control subprogram at the button TCP, and Car window electric machine gets into the PWM soft start stage.The PWM soft start was divided into for 10 steps, per step 20ms, and dutycycle is increased to 100% gradually from 10%.Get into the duty that rises or descend with rear motor.After power windows adopts the PWM control mode, starts comparatively steadily, the startup rapidity is good.

Claims

1. the automotive window electric controller based on the CAN bus is characterized in that having four CAN Node Controllers, is respectively left front window motor master controller, right front window motor sub-controller, left back window motor sub-controller, right back window motor sub-controller; Four Node Controllers are connected with the CAN bus respectively, realize the communication between four vehicle window controllers through the CAN bus; Operate left front window master controller except can controlling left front window glass up-down, can also communicate by letter with the motor sub-controller of its excess-three vehicle window, control the up-down of corresponding glass for vehicle window through sub-controller through the CAN bus; The hardware circuit of four CAN Node Controllers is made up of single-chip microcomputer, photoelectrical coupler, bus transceiver and power drive chip four parts.

2. a kind of automotive window electric controller based on the CAN bus as claimed in claim 1 is characterized in that said single-chip microcomputer is the PIC18F258 single-chip microcomputer.

3. a kind of automotive window electric controller based on the CAN bus as claimed in claim 1 is characterized in that said photoelectrical coupler is the 6N137 high-speed photoelectric coupler.

4. a kind of automotive window electric controller based on the CAN bus as claimed in claim 1 is characterized in that said bus transceiver is the PCA82C250 bus transceiver.

5. a kind of automotive window electric controller based on the CAN bus as claimed in claim 1 is characterized in that said chip for driving adopts the power drive chip MC33486 of motorola inc.