Modeling and implementation of a high-speed high-efficiency DC-DC converter for portable devices

• Main Author: Harsono, Steven Loekita
• Other Authors: Gwee Bah Hwee
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Electronic circuits; DRNTU::Engineering::Electrical and electronic engineering::Integrated circuits
• Online Access: http://hdl.handle.net/10356/77395
• Institution: Nanyang Technological University

Switched Mode DC-DC Converters (SMCs) are required for portable devices to achieve high power-efficiency. The conventional SMCs use external passive components. To reduce the physical size, the state-of-art SMCs is integrated with the on-chip passive components with the cost of lower power-efficiency, which results for lower battery life. This integration of passive components increases the equivalent series resistance (ESR) of the passive components which is now comparable with the output load. Further, as the on-chip inductor is low in quality, smaller die area means lower inductance for the SMC. To still operate in Continuous Conduction Mode (CCM), high switching-frequency (>100 MHz) and higher power consumption is required due to power switches and skin effect. This project involves comprehensive review of a DC-DC converter, derivation of the power loss expression for bonding-wire inductor in high-frequency, derivation of the power-efficiency expression for the overall high-frequency SMC, and verification of the derived expressions by comparing with computer simulation. Design steps for implementing the SMC with emphasizes in power efficiency is presented. The schematic uses 180 nm CMOS process, 100 MHz switching-frequency, 1.8 V input voltage, and 10 nH bonding wire. The simulation obtained 83.29% power-efficiency.