【RAE1】Magnetic levitation toys

The main control of the magnetic levitation toy based on Renesas MCU
uses Renesas RA2E1 MCU. In order to avoid interference from strong magnetic fields, the PCB is divided into two layers.
    The upper layer is the actuator, which uses four electromagnetic coils with a diameter of 19mm and a height of 12mm. In addition, there are 8 sets of neodymium magnets. Each set of magnets is stacked with 4 magnets with a diameter of 12mm, a thickness of 4mm, and an opening of 3mm. The magnet and electromagnetic coil are fixed on the aluminum-based structural board with M3 screws.
    The lower layer is the control unit: the power input is 12VDC, which is converted into 5V through the MP1484DCDC step-down chip and supplied to the Renesas microcontroller and Hall sensor. 5V is converted into 3.3V through the 1117 3v3 and supplied to the Espressif ESP32C3 co-processor and OLED screen.
    Focus on the lower PCB Distribution: There is a Hall sensor in the middle of the board, model 49E. When the magnetic flux passing through the sensing surface of the Hall sensor is 0, the sensor outputs 1/2*VCC. The greater the magnetic flux passing through the front, the higher the output voltage, and vice versa. Low, and the magnetic flux and output voltage have a linear relationship. So this sensor is also called linear Hall. This work uses this sensor as signal input.
    I won’t go into details about the power supply part, just follow the design and layout of the typical circuit of the chip.
    The processor chosen is Renesas RA2E1, with a maximum frequency of 48MHz. Thanks to the strong support of Lichuang EDA and the Renesas ecological community, the circuit layout follows the typical circuit layout in the chip hardware manual.
    Three ADCs were selected to collect the voltage of the 49E Hall sensor, which are the X-axis, Y-axis and Z-axis. The XY-axis voltage will be sent to the PID algorithm to calculate the voltage value of the float balance position, and output the PWM signal. Enable the L293DD motor driver chip to control the two sets of coils on the XY axis to control the float to reach the equilibrium position.
ESP32C3 is also added to the PCB as a co-controller, which together with the LCD screen forms a small TV function.  
 
Software debugging is still in progress