limit volt u00d7 time product of the transformer the pulse width so formed is biased to be inversely proportional to load current flowing through the primary leg of the transformer when transformer t1 is triggered at a constant rate a self adjusting pulse width switching power regulator emerges fig2 shows the waveforms relevant to the operation of the constant power regulator during a charge cycle of load capacitor c3 the voltage and current waveforms present at various points a through g of fig1 are identified by the corresponding letters a g of fig2 for a typical charging cycle the voltage charges in accordance with fig2 b as a result of the composite load current fig2 g the product of the instantaneous voltage b and the instantaneous current g is nearly constant over the entire charge cycle the input power variation is only plus or minus 11 percent a over the cycle as is dictated by the open loop characteristics of the constant power regulator composite current g consists of collector current e and free wheeling diode current f the average collector current during all switching intervals of q1 are substantially the same whereas the free wheeling diode current varies inversely to the capacitor charge voltage.