External pad isolation power switch for rram security

A resistive random-access memory (RRAM) device, comprising:

• an external pad node;
• an internal node;
• and
• a pad isolation switch coupled between external pad node and the internal node, the pad isolation switch comprising:
• a first pair of transistors arranged in series between an external pad node and an internal node, the first pair of transistors coupled together with a connector node;
• a second pair of transistors arranged in series between a supply voltage and the connector node;
• a first high voltage selection circuit having a pair of inputs coupled to the external pad node and a supply voltage VDDW;
• and
• a first level shifter having an output coupled to a gate of a first transistor of the first pair of transistors and an input coupled to an output of the first high voltage selection circuit.