Wiring boards for array-based electronic devices

A lighting system comprising:

• a lightsheet comprising:
• a substantially planar substrate;
• disposed on the substrate, (i) first and second spaced-apart power conductors each extending in a first direction and (ii) a plurality of conductive traces;
• a plurality of light-emitting strings, each light-emitting string (i) comprising a plurality of interconnected light-emitting elements spaced along the light-emitting string, (ii) having a first end electrically coupled to the first power conductor, (iii) having a second end electrically coupled to the second power conductor, and (iv) being oriented in a second direction not parallel to the first direction, wherein the power conductors supply power to each of the light-emitting strings;
• and
• a plurality of control elements each (i) electrically connected to at least one light-emitting string and (ii) configured to utilize power supplied from the power conductors to control the current to the at least one 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.