| With the evolution of the automotive industry, people are comfortable driving environment requires constant improvement of automotive electronics has become an essential part of the car. With the evolution of the automotive industry, motorist's requirements of driving environment are increase. The automotive electronics has become an essential part of the car. This does not only include traditional electrics, such as: windows control, lock control and other simple control modules, also include the in-car entertainment system, automatic air conditioning system, ISS systems etc. Automotive electrical systems become more complex, device control gradually increase the difficulty. Meanwhile, in the existing system, each system has its own control module, so the cost increase also can not be discounted. Some major car companies began to integrate these controllers, one controller or a host controller plus a few auxiliary controllers can be centralized control of all electric car. It becomes the body controller.With the deepening of the study, body control of several controllers from a simple integrated with intelligent control of the vehicle toward the power optimized to improve ride comfort of people's direction. Body controller divided into: power internal acquisition module, the main control module, input module, output control module.Based on the vehicle's power of analysis, we design out of the application of electricity in the collection module of the body controller.Vehicle power system can be divided into two parts, one is power supply system, and the other part is the electrical system.The power supply system composed by the generator and batteries. It takes on the vehicle with electrical power used.When the battery used, it can Occurs the forward current and reverse current, forward current for the output power, the reverse current is charging current. Therefore, the current testing system needs a special way. In this paper, it is using a Hall device current collection. Hall devices due to its characteristics of non-contact measurement, it can be carried forward and reverse current test. In this design, we selected the ACS758ECB-100B of Allegro's.In tests with the electrical system, electrical system parts according to the characteristics of the current-voltage and characteristics of electrical components. Resistance in the form of sampling is used in the current situation of collection system. The sampling resistor is the Yageo's current sense resistor,R004, current amplifier is Linear's LT6100.For the voltage test module, by analyzing the voltage of the vehicle, particularly when starting voltage drop, in order to reduce interference, by contrast, we selected theΣ-△type ADC. Ultimately we selected Linear Technology's LTC2450. With anti-interference ability to change the chip, the quantization noise is small, high resolution and good linearity advantages.About communications, because it is used in the automotive, so the type of the communication is very important. According to experience, choose the LIN bus communication. Chose the commonly used chip company Freescale MC33399. The chip in the world is used widely in both in reducing costs can be a great contribution. In the power supply module, the selection of the commonly used power chips 78L05. In the circuit used the TVS diodes, in order to avoid a variety of surge pulse component damage.According to the needs of each interface, it should the appropriate choice of the main chip. Freescale Semiconductor is the production of 8-bit series of microcontrollers SG MC9S08SG8. It has a very good price.After Complete the hardware system design, based on the needs to design the software. Including LIN bus protocol, SPI data transfer, system data compensation. Through the PC the data is verified to ensure the accuracy of the data system.Finally, the modules are in the laboratory environment and under the vehicle tested, the test results meet the design requirements. The module can not only use the system in the BCM, and can used in the power balance test in vehicle.
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