On-Chip Current Sensing Approaches for DC-DC Converters

In this paper, methods suitable for sensing the output load current (or current consumption) of analog circuits were studied and analyzed. The main focus was paid on approaches that can be implemented on a chip. The proposed approach for sensing the output current of a DC-DC converter is based on measuring the slope of a voltage sensed by an output bypass capacitor. Such an indirect sensing approach shows better efficiency than a common shunt resistor sensing method. The presented approach was used in a flyback type DC-DC converter. The simulated results prove better voltage conversion efficiency using the proposed indirect measurement approach.