Negative-to-Negative Switch-Mode Converter Offers High Current and High Efficiency

By: Budge Ing

Abstract: An external op amp (MAX4322) enables this switch-mode boost converter (MAX668) to deliver output currents as high as 4A with efficiencies better than 90%. The op amp enables the circuit to regulate with respect to ground (instead of the -5.2V supply-voltage input), thereby avoiding the effect of input variations on the -3.6V output.