A package bondwire based 80% efficiency 80MHz fully-integrated buck converter with precise DCM operation and enhanced light-load efficiency

An 80MHz fixed frequency PWM fully-integrated area-efficient buck converter utilizing standard package bondwire as power inductor with enhanced light-load efficiency is presented which occupies 1.2mm² in 0.13μm CMOS. Package bondwire instead of on-chip spiral metal or special spiral bondwire is utilized as power inductor. Two negative feedback loops are proposed as NMOS gate-drive controller to introduce Adaptive Dead-Time (ADT) and precise DiscontinuousConduction-Mode (DCM) operation with self-eliminated reverse current at high frequency, which frees the accuracy requirement of the package bondwire inductor and boosts up the light-load efficiency over 72% at 10mA while reaches 80% at 270mA with a 6.7nH inductor. 8 times efficiency improvement at 10mA is observed comparing to the situation with all the proposed function disabled. Converters with different package bondwire inductors from 3nH to 10nH are tested to verify the robustness.