Stratix IV VCCBATT current requirement

Hi,

Please can you suggest what type of Non-volatile battery power source required to be connected to VCCBATT for security volatile key register.

What will be the current requirement for VCCBATT?

If it is very low(uA), can I use a 3V Lithium button/coin cell?

Please suggest.

Regards,

Sachin.M.kurawatti