Gracefully Degrading Circuit Controllers Based on Polytronics

polymorphic electronics, polymorphic gates, digital circuit controllers, dependability

This paper proposes utilisation of polymorphic electronics to design digital circuit controllers that gracefully degrades when some inconvenient situation arise, e.g. when battery goes low or a chip temperature cross some safe level. In proposed approach, the next state logic of the controller is designed using polymorphic gates. Polymorphic gates exhibit two or more logic functions in according to a specific condition (e.g. Vdd level or special signals). This allows to make a smart reconfiguration of the circuit. An algorithm for designing gracefully degrading circuit controllers using polymorphic gates is proposed in the paper. Purpose of the algorithm is demonstrated on an example of a controller. This controller was physically realised and its functionality (especially in transient state) was verified.