what is the Difference between RCBO & IDPN vigi?

The difference between the two is the isolation of Neutral, (RCBO's do not have isolation of neutral), and also the physical size (RCBO's are slim in design compared to iDPN Vigi) and the sensitivity (iDPN have 300mA range also).
The iDPN Vigi has got all the three protection i.e. Short Circuit, Overload, and Earth leakage.