Apparatus including selectable circuit placement mechanism and methods of manufacturing the same

A semiconductor package, comprising:

• a microcontroller;
• at least one memory device;
• and
• a substrate having the microcontroller and the at least one memory device mounted thereon, wherein the substrate includes:
• a substrate top surface;
• one or more unused contact surfaces exposed on the substrate top surface and unconnected to the microcontroller and the at least one memory device;
• active contact surfaces exposed on the substrate top surface and electrically connected to the microcontroller and the at least one memory device;
• internal electrical connections on or within the substrate and electrically coupling the active contact surfaces, the one or more unused contact surfaces, or a combination thereof;
• an etch back artifact including a conductive structure extending vertically above from the internal electrical connections toward the substrate top surface and buried under the top surface with a top portion of the etch back artifact unconnected;
• and
• a remaining selector portion exposed on the substrate top surface, wherein the remaining selector portion is connected to the internal electrical connections using a via.

A printed circuit board, comprising:

• a processor mounting portion configured to receive and provide electrical connections to a microcontroller;
• a memory mounting portion separated from the processor mounting portion and configured to receive at least one memory device;
• a first set of contact surfaces configured to support a first circuit placement configuration representative of having additional memory devices stacked over or under the microcontroller;
• a second set of contact surfaces configured to support a second circuit placement configuration representative of having the microcontroller unstacked and two or more stacked memory devices at the memory mounting portion;
• a first routing connection electrically connecting the first set of contact surfaces to the electrical connections configured to connect to the microcontroller;
• a second routing connection electrically connected the second set of contact surface and extending toward the first routing connection;
• and
• an etch back selector on a top surface of the printed circuit board, the etch back selector disposed between and electrically connecting the first and second routing connections, wherein the etch back selector is configured to selectively break a connection between the first and second routing connections using an etch back process to select between the first and second circuit placement configurations.