A Dual-Input, Digital Hybrid Buck-LDO System Featuring Fast Load Transient Response, Zero-Wire Current Handover & Input PDN Resonance Reduction

A dual-input, digital hybrid buck-LDO system featuring 300MHz Fully-Integrated Voltage Regulator (FIVR) and Computational Transient Management Controller (CTMC) based Low Dropout (LDO) regulator is presented. The high speed, parallel CTMC-LDO reduces the FIVR input resonance (82% pk-to-pk voltage-swing reduction). The CTMC-LDO operates without any communication with FIVR and can act as a clamp (54% droop & 69% settling time reduction) or share current (0-100%) in parallel with the FIVR, thus increasing load capacity.