Level Shifter Circuit Question
A GPIO high will produce a drain voltage of ~0 at the first FET. Without the divider, this produces essentially VDD between gate and source of the second FET. A VDD of 30 volts greatly exceeds the maximum gate voltage, typically 20 volts. With a 2:1 divider, a VDD of 30 volts produces a gate voltage of 20 volts, while a 6 volt VDD will produce about 4 volts.