A Load Current Sensing Circuit for BUCK Switching Regulator
Baolong Guo · Research & Progress of SSE Solid State Electronics · 2009
By adopting CSMC 0.5μm CMOS process,a novel load current sensing circuit is presented for DCM of BUCK switching regulator. Different from the traditional inductor current sensing circuit,the sensing of load current is realized by detecting the gate driver signal of synchronous MOSFET which changes with the load current simultaneously. The measurement result shows that the proposed current sensing circuit works normally in the fabricated chip for verification. The circuit occupies only 1.5% area of the chip. Comparing with traditional method,the area is reduced by 21% and power dissipation is only 40% of that.