LMH6321: CL pin of LMH6321

hi,

I am using  LMH6321 as a buffer driver for video Line.Output of the DAC is converted to voltage and given to this IC.

Can  PIN no  2 i.e,  CL be left open?

If not what should be the VCL value? Its given in datasheet  that via resistor it should be connected to VCL.

Thanks,

Seema