Linear technology corporation offers the ltc3810 switching regulator controller. This switching regulator controller can directly step down voltages from 100v to output voltages ranging from 0.8v to 93 per cent of input voltages. The design of the single inductor eliminates the need for a transformer. This switching regulator controller delivers very low duty cycles and extremely fast transient response with accurate cycle-by-cycle current limit without requiring a sense resistor.
