A 4–40 V Input Floating–Ground GaN-Based Buck–Boost Converter With Pre-Charge Function for Enhanced Power Efficiency
Year: 2025
Type: article
Abstract: Many applications including automotives demand DC-DC power converters that can cover wide input range with improved power efficiency. This paper presents a 4–40 V input, Gallium Nitride (GaN) based non–inverting buck–boost converter incorporating several methods to improve power efficiency. It employs a new floating–ground three-state four-switch topology along with a pre–charge gate driver for the low–side GaN switch, a Dual Duty–Cycle Controller (DDCC) and an Inductor Peak Current (ILPEAK) adjusting Module (IPCM). The floating–ground technique alleviates the voltage stress on the high–side power switch and minimizes the inductor current ripple ΔIL, resulting in reduction of both switching power loss and conduction power loss. Additionally, the floating-ground topology together with a pre–charge gate driver for the GaN switch achieves a precise pre–charging time duration, preventing reverse conduction during the switch dead time. Consequently, the converter optimizes the power efficiency especially in the buck–boost mode (forVINof 10–14 V in design). The DDCC determines precise duration of each state for the three–state operation and maintain seamless transition across different modes. The ICPM enables adjustingILPEAKthrough indirectly sensingILand the output voltageVOUTfollowed by the DDCC. With the proposed techniques, the reverse conduction of the low-side switch is minimized, and a 2% peak efficiency improvement is achieved in the buck–boost mode. Operating at 2 MHz covering 4–40 V input to a 24W (12 V and 2 A) output, this buck-boost converter achieves a peak efficiency of 92%.
Source: IEEE Access
Language: English
Topic: Advanced DC-DC Converters
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,075
OpenAlex ID: W4411336787