Wiring boards for array-based electronic devices

A lighting system comprising:

• a substantially planar flexible lightsheet;
• disposed on and extending along opposing edges of the lightsheet, first and second spaced-apart power conductors each extending in a first direction;
• a plurality of light-emitting strings disposed on the lightsheet and extending along a second direction substantially perpendicular to the first direction, each light-emitting string (i) comprising a plurality of interconnected light-emitting elements spaced along the light-emitting string, the light-emitting elements being connected in series, (ii) having a first end electrically coupled to the first power conductor, and (iii) having a second end electrically coupled to the second power conductor, wherein (a) the power conductors supply power to each of the light-emitting strings, (b) none of the light-emitting strings extends beyond an area spanned by the first and second power conductors, and (c) none of the light-emitting strings intersects another light-emitting string;
• and
• a plurality of control elements each (i) electrically connected to a different light-emitting string and (ii) configured to utilize power supplied from the power conductors to provide a substantially constant current to the light-emitting string to which it is electrically connected,
• wherein the lightsheet is separable, via a cut spanning the first and second power conductors and not crossing a light-emitting string, into two partial lightsheets each comprising (i) one or more light-emitting strings, (ii) one or more control elements, and (iii) portions of the first and second power conductors configured to supply power to and thereby illuminate the one or more light-emitting strings of the partial lightsheet, and
• wherein, over the lightsheet, the light-emitting elements are spaced apart at a substantially constant light-emitting-element spacing, in both the first direction and the second direction, the substantially constant light-emitting-element spacing being maintained between both (i) adjacent light-emitting elements within each light-emitting string and (ii) adjacent light-emitting elements on different light-emitting strings, independent of positions of the control elements each electrically connected to a different light-emitting string.