Remember there are no rules here. The broker will give you the facility based on their perception of risk. There are different models. Some offer 50:50 while some will offer 75:25. There are also other brokers who may offer 100% margin on stocks alone. You can discuss with your broker as to what you actually require and more often than not your broker will be happy to find a solution for you. But use this facility very sparingly and very cautiously. Just because your broker offers you 100% stock margin does not mean that you go overboard using the stock as margin to trade intraday. That is not a good idea. You may end up with an intraday loss and the onus will be on you to make good the loss. So use this facility very sparingly.
Again remember one thing here. No broker will give you 100% of the value of your shares. For liquid shares, you can get up to 50% margin and at times it will be lower than that. That means on a portfolio of Rs.2 lakh, you can get up to Rs.1 lakh ahs notional margin to trade intraday. When you are using stock as margin to trade intraday, make it a point to always set strict stop loss and profit targets. Secondly, always set cover orders or bracket orders so that the risk management is automatic. Thirdly, use the stock as a margin facility for trades where you have a high conviction.