Inventive embodiments include a device for distributing power to devices over an area, with a power density of at least one Watt per ft2 (or 900 cm2 if we go metric). The device includes a flexible substrate; a circuit comprising a thin-film conductor having a thickness of 400 nanometers or less, wherein the circuit is adhered to the substrate; a plurality of devices positioned on the sheet and attached to the circuit wherein each device of the plurality is driven at substantially the same voltage; and the power delivered to the devices is at least 90% of the input power of the energized circuit.