V th can be expressed as the voltage between gate and source when the low operating current value is I D =−1mA for this product. For normal switching operation, V GS (on) requires a higher voltage than V th, and V GS (off) requires a lower voltage than V th.
(The relationship can be established as follows: V GS (off) < V th < V GS (on) )
Take this into consideration when using the device.