next oscillator pulse triggers the main switch to return to the on state alternatively main switch 121 can be made to remain off when the regulator is operating in burst mode and certain conditions are met in burst mode main switch 121 and synchronous switch 122 operate intermittently at light loads in order to increase efficiency by minimizing switching losses additionally in burst mode the current reversal comparator 116 is enabled and the inductor current is not allowed to become negative current reversal comparator 116 monitors the current flowing through synchronous switch 122 and signals logic 112 to shut off synchronous switch 122 when the inductor current becomes negative during burst mode operation transistors 151 and 152 of burst clamp circuitry 150 clamp the minimum value of the buffered ith voltage at the burst threshold level thereby setting the minimum peak inductor current level iburst the voltage on ith is then monitored by burst comparator 119 to determine when sleep mode is enabled and disabled when main switch 121 turns on the inductor current has to increase to iburst before it can shut off then as the output load current drops the peak inductor current decreases to keep the output voltage in regulation when the load current demanded drops to a current less than iburst minus one half of the ripple current in the inductor however the burst threshold forces the peak inductor current to remain equal to iburst since the average inductor current is greater than the output load current the voltage on ith will be reduced by error amplifier 117 until the burst comparator 119 trips when burst comparator 117 trips sleep mode is enabled and.