A 3D device, the first level including first transistors and a first interconnect; a second level with second transistors overlaying the first level; a third level with third transistors overlaying the second level; a plurality of electronic circuit units (ECUs), where each ECU includes a first circuit with a portion of the first transistors, where each of the ECUs includes a second circuit including a portion of the second transistors, where each of the plurality of ECUs includes a third circuit, which includes a portion of the third transistors, where each of the ECUs includes a vertical data bus, where the vertical data bus has between eight pillars and three hundreds pillars, where the vertical data bus provides electrical connections between the first and second circuits, where the third level includes an array of memory cells, and where the second circuit includes a memory control circuit.