DC/DC converter with reduced power consumpton and improved efficiency

摘要

A comparator monitors an output voltage Vout. When an output voltage Vout decreases to a predetermined output voltage or less, the comparator sends a signal that represents this state to a controlling circuit. When the controlling circuit receives the signal, it causes a switching device to be turned on. Thus, a coil current IL is increased. A hysteresis (window) comparator monitors the coil current IL. When the coil current IL reaches a comparison current ILP, the controlling circuit causes the switching device to be turned off. When the coil current IL decreases to the comparison current ILB (where ILP>ILB), the controlling circuit references an output signal of the comparator. When the output voltage Vout is lower than the predetermined output voltage, the controlling circuit causes the switching device to be turned on.