Comment on POA - Power of Attorney for your Demat account
Ajay, if you intend to pledge shares then you will need to open a new demat account with us. For trading F&O you need to open only trading account with us, but if you intend to pledge then both trading and demat.
You cannot pledge the shares directly from your ICICI DP.
Presently, you just need to send an email request to pledge/unpledge, you will soon have an online module for doing the same, but yeah it is online and no paper work involved. One round trip of pledging and unpledging will cost you around Rs 60/scrip including all charges.