Power management unit for smartphone applications

• Main Author: Kok, Chiang Liang
• Other Authors: Siek Liter
• Format: Theses and Dissertations
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/66366
• Institution: Nanyang Technological University

The escalating demand for modem smartphones has propelled the urgency for a longer and more sustainable battery lifetime to be used in portable devices. More enhancements heap greater pressure on the lifetime of the battery and escalate the need for a more efficient power management unit (PMU). However, the commonly used NiCd/NiMH and Li-Ion batteries, providing the main source of power is limited in supplying the energy and power demands for the wide variety of application found in a smartphone. This is supported by the fact that its energy density has only doubled over the past few decades from 300 to merely 600Whr/liter. Hence, the feasible solution is to reduce the overall power consumption by improving the power efficiency of the PMU in a smartphone. Therefore, the key is to improve the power efficiency of the DC-DC converter which is one of the most important circuit blocks in the PMU which includes the Low Dropout regulator and bandgap reference circuit. Therefore, since the smartphone spends most of its time in the light-load condition, measures mu^t be in place to improve the light-load efficiency. In this thesis, there are mainly two proposed work: (1) A Twin Frequency Control DC-DC Buck Converter Using Accurate Load Current Sensing Technique for 3G/4G Smartphone Applications and (2) A Hybrid Deadtime and Reverse Inductor Current Control System for Smartphone Applications.