03F4 Internal Circuit Details
▶ 03F4 Board Details:
➔ Board Number: 03F4
➔ Board Full Number: TXW-001-v1.3-003F4
➔ Hardware Version: V1.3
➔ Software Version: V1.3
▶ 1. Main Power IC/CPU
➔ Main Power IC/CPU Number: BP0P325-56A4
➔ Main Power IC/CPU Brand Name: JL
➔ Main Power IC/CPU Description: The BP0R164-03F4 is a dual-function chip serving as both the main power management IC and the central processing unit (CPU) for the device. This integration allows the chip to manage power distribution across the board while also handling computational tasks such as Bluetooth communication, audio processing, and control of peripheral components.
➔ Pin Count: With 20 pins, this IC is designed to handle multiple tasks, including power regulation, battery charging management, data processing, and I/O control. The pins likely include power inputs, outputs for regulated voltages, communication interfaces, and GPIOs for controlling LEDs, the microphone, and other components.
➔ Functions And Working: The IC regulates voltage, ensuring stable power delivery to the CPU and peripheral components. It also processes digital signals, handles Bluetooth communication, and may have integrated power-saving features to optimize battery life.
▶ 2. Charging Transistor
➔ Charging Transistor Number: mAE2A
➔ Charging Transistor Description: The mAE2A is a charging transistor that plays a critical role in controlling current flow from the charging source to the battery. Unlike a charging IC, this transistor is a more straightforward component used to switch and regulate the charging process based on signals from the main power IC.
➔ ChargingTransistor Total Pin: 3 Pin
⤷ This transistor has 3 pins, likely including the gate, source, and drain. The gate pin receives a control signal from the main IC, which turns the transistor on or off, allowing current to pass through to the battery.
➔ Charging Connector Type: The charging connector is a Type C, which is a modern standard for USB connectors. It is reversible, meaning the cable can be plugged in either way, and it supports higher power levels, making it suitable for fast charging.
▶ 3. Charging Indicator LED
➔ Charging Indicator LED Color: Red
➔ Red LED: This LED is likely connected to the charge status output of the charging IC (AyEAE). When the device is charging, the IC pulls the pin low or high (depending on the design) to light up the LED, indicating the charging process.
➔ Operation And Working: The red LED remains on during charging and turns off when the battery is fully charged, or it may change colour or blink to indicate different charging states (e.g., full charge, charging in progress, or fault condition).
▶ 4. Bluetooth On LED
➔ Bluetooth On LED Color: Blue
➔ Blue LED: The blue LED serves as an indicator for Bluetooth status. When the device’s Bluetooth function is active, this LED will light up, indicating to the user that the device is discoverable or connected.
➔ Operation And Working: This LED is controlled by the Bluetooth module on the board. It could be connected directly to a GPIO pin of the Bluetooth chip, or it might be driven by a transistor circuit if more current is needed.
▶ 5. Crystal Oscillator
➔ Crystal Oscillator Frequency: The crystal oscillator operates at 26MHz, which is a common frequency used in Bluetooth systems for generating the clock signal necessary for the digital circuits in the Bluetooth chip.
➔ Crystal Oscillator Pins: The crystal has 4 pins, two of which are typically connected to the ground, and the other two are connected to the oscillating circuit inside the Bluetooth module.
▶ 6. Microphone
➔ Microphone Number: SH-018
➔ Microphone Type: The SH-018 is a small, electret condenser microphone, which converts sound waves into electrical signals.
➔ Microphone Total Pin: 2 Pin, one for the signal output and one for the ground.
➔ Microphone Operation And Working: This microphone is used to capture audio input, such as voice commands or calls. The signal from the microphone is typically very low voltage and needs amplification, which might be done by an external amplifier circuit or an integrated audio codec in the Bluetooth chip.
▶ 7. Battery:
➔ Battery Model: XD 481036
➔ Battery Type: Rechargeable Li-Polymer Battery
The battery is a rechargeable Li-Polymer battery, which is known for its high energy density, lightweight, and flexibility in shape.
➔ Battery Capacity: 3.7v,150mAh
⤷ The battery has a nominal voltage of 3.7V and a capacity of 150mAh, which is typical for small, portable devices that require compact power sources.
➔ Battery Designation: 1ICP5/11/38 indicates the battery's classification and size in millimetres.
➔ Battery Operation And Working: This battery powers the entire board. The charging IC (AyEAE) ensures that the battery is safely charged to its full capacity without overcharging, which could damage the battery or reduce its lifespan.
▶ 8. Charging Input Specifications
➔ Charging Input Voltage: 5 Voltage
⤷ The device is designed to be charged with a 5V input, which is standard for USB power sources. This voltage is stepped down by the charging IC to match the battery’s charging requirements.
➔ Charging Input Ampere: 2 Ampere
⤷ The device can accept up to 2A of current during charging, allowing for relatively fast charging given the small capacity of the battery.
➔ Charging Time Load Voltage: 3.9V
⤷ 3.9V is a typical voltage during the charging process of a Li-Polymer battery.
➔ Charging Time Load Ampere: 0.2A
⤷ 0.2A indicates the current being drawn by the battery as it charges, which likely reduces as the battery approaches full charge to prevent overcharging.