built-in led turn on when I use this lib

[steamlinux]

It's normal behavior?

[mcauser]

I'm not sure what microcontroller you are using this with, or what pins you are using for DIO/CLK.
My only assumption is that one of the GPIOs on your board is also used to drive the onboard LED.

The library doesn't use any hardware I2C or SPI. Just bit-banging, so you can use any GPIOs. To avoid the LED flickering, simply use a different GPIO.