A novel current sensing circuit for Boost DC-DC converter

Current sensing is one of the most important functions on current mode DC-DC converters. A novel on-chip current-sensing technique, which is suitable for a current mode control DC-DC Boost converter, is presented. the proposed current sensing circuit insert a resistor in the path of the current to be sensed, it doesn't need an amplifier as a voltage mirror, also can achieve high accuracy and fast response. The Circuit was designed based on TSMC 0.35um CMOS process, Simulation results shows the current sensing circuit had an accuracy in the 2.5V-5.5V power supply, and the simulation result shows that the sample accuracy as high as 96%.