A Compact High-Efficiency Boost Converter with Time-Based Control, RHP Zero Elimination and Tracking Error Compensation

Time-based signal processing has been recently demonstrated to be more area- and power-efficient compared with traditional analog-based, making it an interesting approach for the design of compact high-efficiency DC-DC converters for portable applications. This work presents a novel boost converter, with a time-based control, a scheme for RHP zero mitigation requiring no extra power switch nor external capacitor, and a PFM operating mode with steady-state error correction and seamless PFM-to-CCM transition. The prototype implemented in a 0.18- $\mu$ m BCD process generates an output voltage of 5 V from an input voltage ranging between 2.5 V and 4.5 V, and has an 800-mA load current capability. The controller area occupation is 0.27 mm $^{2}$ and the quiescent current in CCM is 300 $\mu$ A for the controller and 40 $\mu$ A for the tracking error compensation. The peak efficiency is 96 $\%$ at 4.5-V input and above 90 $\%$ at light loads down to 50 mA current. Compared to a peak-current mode control, both the controller area and the current consumption of the proposed time-based architecture are lower by about 40%. The achieved closed loop bandwidth of 130 kHz is six times larger than in a conventional boost converter with RHP zero.