A switching power supply is modified to mitigate potentially adverse
effects of near zero loads on power delivery. In one example, a
processor-controlled dummy load is coupled to the power supply output in
addition to an actual load. The dummy load is controlled so that at least
some minimal load is presented to the power supply when the actual load
is drawing low or near zero power. In another example, the feedback loop
of the switching power supply is modified to mitigate the effects of a
potential overvoltage condition in a bias supply from which the switch
controller of the power supply draws power, which condition may occur at
low or near zero load power. A lighting system may include a switching
power supply thusly modified to provide power to a variable load that
includes one or more LED-based lighting apparatus.