Device and method of establishing sleep mode architecture for NVSRAMs

A device is configured to establish first and second device power domains. Isolation circuits isolate signals from passing between circuits in the first device power domain and circuits in the second device power domain. During a transition between power domains, an n-bit value is stored in a particular storage location, and compared to a particular n-bit value. Isolation between the first and second device power domains is removed when the n-bit value stored in the particular storage location matches the particular n-bit value.