Hello Hualong,
Yes, you can still implement the wireless charging functions if you don’t use these 2 pins.
The pins 3 and 4 (SDA and SCL) are for the I2C interface as part of the support interface for the NXQ1TXH5.
The NXQ1TXH5 is an easy to use fully integrated chip that can be completely configured by means of external resistors so in general there is no need for customers to have access to the I2C bus to configure the chip.
You can check section 2.1.7 Support interface for the application note AN11775 https://www.nxp.com/docs/en/application-note/AN11775.pdf
Have a great day,
Paulina
