"Windshield wiper speed controller PCBA" refers to the automobile windshield wiper speed controller printed circuit board assembly. The following is a detailed introduction to it:

　　Overview

　　The automobile windshield wiper speed controller PCBA is a key component of the automobile wiper system. It is mainly used to control the operating speed of the wiper to adapt to different weather and road conditions, ensuring that the driver has a clear view in rainy days or other bad weather. It receives various input signals and processes and analyzes these signals to accurately adjust the motor speed of the wiper, thereby realizing different working modes of the wiper, such as intermittent wiping, low-speed wiping, high-speed wiping, etc.

　　Components

　　Microcontroller (MCU): As the core of PCBA, the microcontroller is responsible for executing control algorithms and logic processing. It receives signals from various sensors and control switches, judges the current needs according to the preset program, and sends corresponding control instructions to the wiper motor drive circuit to adjust the speed and working mode of the wiper. There are many common microcontroller models, such as some low-power, high-performance single-chip microcomputers, which can meet the real-time and stability requirements of wiper control.

　　Sensor interface circuit: connects various sensors, such as rain sensors. Rain sensors can detect the amount of rainfall and convert the signal into an electrical signal for transmission to the microcontroller. The microcontroller automatically adjusts the speed of the wiper according to the amount of rainfall to achieve intelligent wiping function. In addition, a vehicle speed sensor may also be connected to adjust the operating frequency of the wiper according to the vehicle speed, and appropriately increase the wiper speed when driving at high speed to ensure a better field of vision.

　　Control switch interface circuit: connected to the wiper control switch on the car dashboard, receiving signals from the driver's manual operation, such as selecting intermittent wiping, low-speed wiping, high-speed wiping, and inching wiping. These signals are transmitted to the microcontroller through the interface circuit, and the microcontroller controls the operation of the wiper according to the driver's instructions.

　　Motor drive circuit: according to the instructions of the microcontroller, provide a suitable drive current for the wiper motor to control the speed and direction of the motor. Power devices such as power transistors or field-effect transistors are usually used to drive the motor, and have overcurrent protection, overheating protection and other functions to ensure the safe operation of the motor and circuit.

　　Power management circuit: Converts the voltage provided by the car power system (usually 12V or 24V DC) into a stable voltage suitable for the operation of various chips and circuits on the PCBA, such as 5V, 3.3V, etc. At the same time, the power management circuit also has power filtering, voltage stabilization and protection functions to prevent power fluctuations from affecting the circuit.

　　Storage circuit: Generally composed of storage devices such as EEPROM, used to store relevant settings and parameters of the wiper, such as the time interval of intermittent wiping, the wiper speed adjustment coefficient at different vehicle speeds, etc. These data can still be saved after the vehicle is powered off, and the microcontroller can read these data at the next startup and restore to the previous setting state.

　　Working principle

　　Signal acquisition: The sensor interface circuit collects signals from the rain sensor and speed sensor in real time, and the control switch interface circuit receives signals from the driver's manual operation, and converts these signals into digital signals that the microcontroller can recognize. For example, the rain sensor generates electrical signals of different intensities according to the amount of rainfall, which are transmitted to the microcontroller after being processed by the interface circuit.

　　Data analysis and decision-making: The microcontroller analyzes and processes the various signals received, and determines the current working mode and speed requirements based on the preset algorithms and logic. For example, when the rain sensor detects a large amount of rainfall, the microcontroller will automatically select the high-speed wiper mode; when the vehicle speed is high and the rainfall is moderate, the microcontroller will appropriately increase the wiper frequency.

　　Command output: The microcontroller sends corresponding control instructions to the motor drive circuit based on the analysis results. The motor drive circuit adjusts the output drive current according to these instructions, thereby controlling the speed and direction of the wiper motor to achieve different working modes and speeds of the wiper.

　　State feedback and adjustment: During the operation of the wiper, the motor drive circuit may feedback the working status information of the motor, such as current size, temperature, etc. to the microcontroller. Based on this feedback information, the microcontroller monitors and adjusts the operating status of the wiper in real time. If the motor is detected to be overheated or the current is abnormal, the microcontroller will take corresponding protection measures, such as reducing the wiper speed or stopping the wiper operation, to protect the safety of the motor and circuit.

　　Application scenarios

　　Various passenger cars: widely used in various passenger cars such as sedans, SUVs, MPVs, etc., to provide drivers with a clear view in rainy days or other situations where wipers are needed to ensure driving safety. By accurately controlling the speed of the wiper, it can adapt to different weather and road conditions and improve driving comfort and convenience.

　　Commercial vehicles: Commercial vehicles such as trucks and buses are also equipped with wiper speed controllers PCBA. Since commercial vehicles face more complex and diverse road conditions during driving, the wiper speed controller can automatically adjust the working mode and speed of the wiper according to the actual situation, ensuring that the driver can have a good view in various situations and improve driving safety.