Question about SG3525

I've been reading SG3525 datasheet and application note. Can't find any information and still confuse about SYNC(pin 3), OSC Output(pin 4), and Shut Down(pin 10). I'm not using SYNC(pin 3), OSC Output(pin 4), and Shut Down(pin 10). The pins should be left floating/open circuit or grounded?
Thank you.

Please see https://tahmidmc.blogspot.com.au/2013/01/using-sg3525-pwm-controller-explanation.html

Osco and sync can be used to synchronize another oscillator to the one in the '3525, you dont need to connect these if your just using one '3525, they can be left open.
Shutdown is a rapid shutdown input, connecting this pin to ground makes the chip run constantly, connecting it to vref shuts the chip down, this i/p can be used as an overcurrent shutdown (there are various way to do this), if you just want to run the chip without protection you can just ground it.