As people's demand for handling and comfort of cars continues to increase, there are more and more electronic devices in the car body, such as electric rearview mirrors, central locking, glass lifts, lights and more. Features, etc. Power requirements and options An important step in the design of a typical body control module (BCM) is to determine the power requirements and choose the right power solution. In general, BCM requires an input voltage between -0.5V and 32V and an output voltage of 5V or 3.3V. It is worth mentioning that there are more and more electric equipment in the car. If the quiescent current of the battery directly powered by the battery is not low enough, and the car is continuously parked for a long time, the car battery may not be restarted due to excessive discharge. Therefore, BCM design needs to consider quiescent current. In addition, automotive applications may often face high temperature environments, so power supplies are required to provide over-temperature protection. Power supplies suitable for BCM include linear power supplies (or linear regulators) and switching power supplies (or switching regulators). These two power supplies have their own advantages. The choice of which power supply depends on the specific application. In terms of the power supply of the body control module, in the cars sold in the Chinese market, cars generally use 12V power, while trucks and buses generally use 24V power. In the 12V power supply BCM, it is recommended to use ON Semiconductor's linear regulator, such as NCV4275A, see Figure 2. The NCV4275A is a 5V, 3.3V/450mA low dropout (LDO) linear regulator with reset and delay. This device supports programmable microcontroller reset and offers a variety of features such as overcurrent protection and overtemperature. Protection, short circuit protection, etc. In addition, a diode (MRA4005) is connected in series at position 1 in the figure below. This linear power supply can effectively prevent reverse voltages up to -42V; a transient voltage suppressor (TVS) tube can be connected in parallel at position 2 to effectively block up to + 45V transient power load dump (loaddump) high voltage pulse and unstable power supply clutter, in line with the ISO16750-2-20034.6 overvoltage test specification for 12V automotive power systems. In fact, a load dump can occur at the moment the car engine starts, causing the battery voltage to rise above 40V. These features make the NCV4275A ideal for automotive body control module applications. In fact, the NCV4275A is only one of ON Semiconductor's wide range of linear regulators for automotive applications. Other linear regulators are such as NCV8664/5, NCV4949, NCV8503/4/5/6, NCV4274A, etc. Ultra-low static power products with quiescent currents as low as 30μA and drive currents ranging from 100mA to 450mA. Figure 1: Schematic diagram of a typical application circuit for a linear power supply in a body control module. In the BCM application of 24V power supply, it is necessary to convert the 24V voltage to 5V or 3.3V. If a linear regulator is used, the power chip itself will have high power consumption, and a large amount of heat will cause the temperature to be too high to burn out the chip. We need to use switching regulators. We recommend the use of ON Semiconductor's switching regulators for automotive applications such as NCV51411, NCV8842, NCV8843, NCV33063, NCV33163, NCV3063, NCV3163, LM2576, LM2575 and NCV2574. These switching regulators have high efficiency, avoiding a large amount of heat release, protecting the chip and improving system reliability. The switching regulator drive currents for these automotive applications are mostly between 0.5A and 1.5A, some reaching 2.5A (NCV33163) and switching frequencies between 50kHz and 300kHz. Taking the NCV51441 as an example, this device uses the V2 control architecture to provide unparalleled transient response, excellent overall regulation accuracy, and the simplest loop compensation. The “BOOST†pin on this device supports “Bootstrapped†operation to maximize power efficiency; the integrated synchronization circuitry supports parallel power operation or minimizes noise. Figures 2a) and b) show typical circuits based on the ON Semiconductor CAN transceiver AMIS-42665 and the LIN transceiver NCV7321, respectively. It is worth mentioning that the AMIS-42665 provides very low quiescent current of less than 10 μA. Supports bus wake-up, common mode voltage range -35 V to +35 V, and can withstand electrostatic discharge (ESD) pulses rated at +/- 8 kV. The NCV7321 supports a voltage range of -45 V to +45 V and is capable of withstanding a 5 kV ESD pulse. These devices offer powerful protection. Figure 2: Typical CAN circuit (Figure a) and LIN circuit (Figure b) based on ON Semiconductor transceivers. In the body control network application, it is necessary to reduce the cost and space requirements as much as possible, and at the same time improve the stability and long-term reliability of the system, so it is necessary to improve the integration of components. Thanks to the mixed-signal processes that have emerged in recent years, such as ON Semiconductor's Smart Power high-voltage BCD process, high-voltage analog circuits can now be integrated with low-voltage circuits, enabling the development and application of higher-integration system chips. S12VR window lift solution to improve safety and quality Freescale's S12 MagniV S12VR mixed-signal microcontroller (MCU) portfolio simplifies automotive engineering by providing intelligent, optimized, integrated, high-precision analog components and proven S12 MCUs. The S12VR series is the first system-in-package device based on the LL18UHV processing technology in the portfolio for automotive and industrial anti-pinch window lift systems, electric sunroof modules, LIN-controlled relay drives, smart actuators, relay-based DC motors and Other space-constrained relay DC motor control applications. The Freescale StarterTRAK TRK-S12VR-WLFT low-cost reference design demonstrates the main advantages of the S12 MagniV S12VR 16-bit MCU for window lift and relay-based motor control. The StarterTRAK has a compact design with fewer external components, can withstand higher voltages, and takes up less space. The solution drives a relay-based DC motor and achieves anti-pinch and window jam detection with a Hall effect encoder. The relay is diagnosed by the HVI wake-up pin. Includes LIN communication capabilities for managing status and diagnostic reports. Target applications include power window systems, sunroof systems, zoning systems, and relay-based DC motor control. Figure 3 S12 MagniV window lift and relay-based DC motor control reference design circuit diagram The software provided by the reference platform can be used as a starting point for the DC motor of the window regulator relay through the anti-pinch detection. It has HAL and MCU initialization, automatic reversal procedures, anti-pinch detection, speed and direction processing, self-calibration and other basic functions required for this application. Edit Comment: This article briefly introduces the analysis of automotive body control module and window design circuit. Based on the typical circuit of ON Semiconductor CAN transceiver AMIS-42665 and LIN transceiver NCV7321, Freescale S12 MagniV S12VR 16-bit MCU is used for car windows. Lift and relay based motor control. Black Lamp,T8 Blb Light,T8 Blb Bulb,T8 Blb Tube Changxing leboom lighting product CO.Ltd. , https://www.leboomuv.com
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