Schematic Review: ATtiny84 based DC Motor & LED Driver with TP4056 and MT3608

[Felmor]

Hey folks, designing my first multi-stage power and driver board. The microcontroller is an ATtiny84. I have attached the full schematic. Are there any critical design flaws, floating pins, or short-circuit risks that you can spot? Appreciate any feedback!

Project Details & Goals:

    Charging: The board utilizes a TP4056 to charge the batteries via a USB-C input.

    Battery: To save board space and keep it lightweight, I am using self-protected Li-Po batteries. Therefore, there is no discrete DW01/FS8205 protection circuit on the schematic.

    Boost Regulator: My goal is a stable 5.1V power rail (P+) for both the MCU and the loads. I set the MT3608 feedback resistors to R3​=75 kΩ and R4​=10 kΩ to achieve this target voltage.

    Microcontroller: An ATtiny84A handles the logic and is powered directly from the 5.1V (P+) rail.

    Motor Driver Layer: The DC motor will be wired externally, so I used Test Points (TP4 & TP5) as solder pads. I am using an AO3400A N-Channel MOSFET for low-side switching.

    Protection & Current Sensing: To suppress inductive voltage spikes, an SS14 flyback diode (D1) is placed in parallel across the motor solder pads. Additionally, to monitor the motor current via the MCU's ADC pin (PA2), I implemented a 500 mΩ shunt resistor followed by a low-pass RC filter (1 kΩ / 1μF).