SI9121 Overview
The Si9121 simplifies the 48-V to +5-V or +3.3-V converter design for ISDN application by integrating the floating feedback error amplifier providing direct output voltage regulation. This approach eliminates the need for an external shunt regulator. The Si9121 also integrates a high voltage depletion mode MOSFET which allows the converter to be powered directly from the high input bus voltage without requiring an...