A--Handle

The charging module
uses the TP4056 chip for battery management, offering the following advantages: • Programmable charging current up to 1000mA • No MOSFET, sense resistor, or isolation diode required • Complete linear charger for single-cell lithium-ion batteries in an SOP package • Constant current/constant voltage operation with thermal regulation to maximize charging rate without overheating • 4.2V preset charging voltage accuracy up to ±1.5% • Charging current monitor output for battery level detection • Automatic recharging • Dual outputs for charging status, including no-battery and fault status indicators • C/10 charging termination • 55uA supply current in standby mode • 2.9V trickle charging device version • Soft-start limits inrush current • Battery temperature monitoring • 8-pin SOP-PP package. The charging current can be adjusted by changing the resistor R13 in the above schematic diagram.
II. Automatic switching circuit between external USB power supply and internal lithium battery power supply

: When no USB power supply is plugged in, the internal lithium battery is used for power.
When a USB power supply is plugged in, it switches to external USB power supply and charges the lithium battery.

1. The final power supply to the system is VCC.
2. Single battery power supply: When no USB is plugged in, the gate (G) of the P-channel MOSFET remains low due to the pull-down resistor. At this time, the MOSFET is turned on, and the battery's VBAT goes through the MOSFET to the switch and then to VCC.
3. Single USB power supply: When no battery is plugged in, the gate (G) of the MOSFET is high after plugging in the USB, the MOSFET is turned off, and VUSB goes through the diode to the switch and then to VCC.
4. Battery and USB connected simultaneously: When VUSB is high, the battery does not supply power to the system through the MOSFET. This is the same as the single USB connection method, but due to the battery connection, the charging section starts working, and the USB simultaneously charges the battery.
III. The joystick
uses an ADC for data acquisition: The joystick is a bidirectional cross 10K resistor. The module uses a 5V power supply. In its original state, the X and Y axis voltages are approximately 2.5V. When the joystick is pushed in a certain direction, the corresponding axis voltage increases or decreases, with a maximum value of 5V and a minimum value of 0V. 1. Operating voltage: 5V 2. Output voltage range: 0~5V 3. Interface: Two analog signals represent X and Y offsets, and one digital signal SW represents whether the Z axis is pressed. For buttons, a standard I/O port is used to detect high and low levels to determine if the button is pressed. An external
WiFi
module can be connected, configuring the handshake protocol. An external Bluetooth module can also be connected.
(3D preview image,
actual product image)