Miniature DC-DC Boost Converter for Driving Display Panel of Notebook Computer

• Main Authors: Seok-Hyeong Ham, Hyung-Jin Choe
• Format: Article
• Language: English
• Published: MDPI AG 2019-07-01
• Series: Energies
• Subjects: backlight; DC-DC converter; passive snubber; voltage stress
• Online Access: https://www.mdpi.com/1996-1073/12/15/2924

This paper proposes a miniature DC-DC boost converter to drive the display panel of a notebook computer. To reduce the size of the circuit, the converter was designed to operate at a switching frequency of 1 MHz. The power conversion efficiency improved using a passive snubber circuit that consisted of one inductor, two capacitors, and two diodes; it reduced the switching losses by lowering the voltage stress of the switch and increased the voltage gain using charge pumping operations. An experimental converter was fabricated at 2.5 cm &#215; 1 cm size using small components, and tested at input voltage 5 V &#8804; <i>V_IN</i> &#8804; 17.5 V and output current 30 mA &#8804; <i>I_O</i> &#8804; 150 mA. Compared to existing boost converters, the proposed converter had ~7.8% higher power conversion efficiency over the entire range of <i>V_IN</i> and <i>I_O</i>, only ~50% as much voltage stress of the switch and diodes, and a much lower switch temperature <i>T_SW</i> = 49.5 &#176;C. These results indicate that the proposed converter is a strong candidate for driving the display panel of a notebook computer.