IO expansion hat for Raspberry PI

According to the DFR0566 datasheet, the IO expansion hat can supply a maximum of 500mA of current in total, shared across all its output pins. However, the PWM signal pin is not designed to supply power to external devices like a fan; it is meant to be used as a control signal for devices with their own power supply.

If you try to power your fan directly from the PWM signal pin, you risk drawing too much current and damaging the IO expansion hat or your Raspberry Pi. Additionally, the voltage on the PWM signal pin will depend on the state of the pin (HIGH or LOW) and the duty cycle of the PWM signal, which can range from 0V to 3.3V.

To safely power your fan, you should use a separate power source, such as a 5V power supply, and connect the PWM signal pin to the fan's speed control input. This will allow you to regulate the fan's speed using the PWM signal without drawing too much current from the IO expansion hat. Be sure to check the fan's datasheet to ensure that it can be safely controlled using a PWM signal.