A method includes an integrated circuit with a memory. The memory operates with an operating voltage. A value of a minimum operating voltage of the memory is determined. The value of the minimum operating voltage is stored in a non-volatile memory location that maybe a non-volatile register. This minimum operating voltage information can then be used in determining when an alternative power supply voltage may be switched to the memory or ensuring that the minimum voltage is otherwise met. The minimum voltage can be used only internal to the integrated circuit or also provided externally to a user.