Implementing a key and a protection circuit in a configurable device. A soft key associated with a protection circuit is combined with a user's electronic design in generating configuration data for download onto the configurable device. The placement and routing of the soft key is pseudo-randomly arranged with respect to the user's electronic design such that its placement and routing on the configurable device is substantially different for binary configuration data that is generated. Hiding the soft key and its connections to the protection circuit and assisting in protecting user electronic designs is achieved.