supplies 20 and 22 preferably 75 w each are formed on layer 14 of pcb 12 as illustrated since the total power of fixture 10 is 130 w in order to maintain the proper dimensions of the the design preferably is split such that each power supply drives half of the leds on the fixture the leds are connected in series forming two distinct circuits driven by two separate power supplies as shown in fig2 all the through hole components 17 connector 19 capacitor 21 capacitor 23 choke 27 and 29 inductors 31 capacitor 33 and 35 inductors 37 capacitor 39 inductor and 41 capacitor are mounted on the bottom layer 16 the through hole components have leads that extend into plated holes vias and are soldered on top surface layer 14 illustrated by reference numeral 24 are mounted to bottom layer 16 the through holes or thermal vias are also used to manage the heat generated by the leds and power supplies the details of using the vias to manage the heat are described in application notes issued for example by osram opto semi conductors gmbh regensburg germany and phillips electronics n v the netherlands suppliers of led emitters the thermal vias 42 thermally connect the high brightness leds mounted on top layer 14 to heat sink 60 secured to bottom layer 16 the vias 42 are plated holes formed on the led pads 40 to provide heat conduction all the holes shown in the figures are vias pcb 12 is mated to heat sink 60 using mounting screws 50 fig8 extending through a plurality of screw holes 51 a high thermal conductivity dielectric 52 fig8 and 9 is inserted between pcb 12 and heat sink 60 a dielectric material which has been successfully utilized is the.