Electronic sensing system with environmental sensor patch

An electronic sensing system, comprising:

• a substrate with a detection region;
• a transceiver formed on a transceiver substrate separate from the substrate and affixed to the substrate, the transceiver including:
• an output pad for making an electrical connection;
• an excitation circuit adapted to provide an excitation signal to the output pad;
• an input pad for making an electrical connection;
• a detection circuit connected to the input pad;
• and
• an interface responsive to a downlink signal to transmit an uplink signal representing the electrical state of the input pad;
• a code circuit separate from the transceiver and disposed over the substrate, the code circuit including a sensor patch disposed over the substrate at least partly in the detection region, the sensor patch having an electrical state that changes with exposure to a corresponding environmental factor and being electrically conductive in an initial electrical state, the output pad and the input pad electrically connected to the code circuit so that the detection circuit detects an electrical state of the input pad in response to the excitation signal and the electrical state of the sensor patch;
• and
• a layer stack disposed over the sensor patch in the detection region, the layer stack including one or more layer(s) in a selected order, each of the one or more layer(s) susceptible to a respective environmental factor, so that the sensor patch changes electrical state in response to exposure of the layer stack to the respective environmental factors of the one or more layer(s) in the selected order and subsequent exposure of the sensor patch to the corresponding environmental factor.