HomeUE Research Bulletinvol. 10 no. 1 (2008)

Upgrading a 4-Watt Self-Oscillating Flyback Converter to 5 Watts

Ernilyn L. De Guzman

Discipline: Engineering



This study involves the upgrading of a 4-watt to a 5-watt charger intended for standard batteries like Lithium-Ion and Lithium Polymer and a no-load output voltage within the range of 5V-6V with a normal temperature range from 0 C to 50 C to extend the range and capacity of the mobile charger.  The study covers the requirements and proper selection of components for a 5-watt mobile phone charger intended for standard products.  However, due to resource restrictions and other requirements that pertain to safety, quality assurance and reliability, and cost reduction, the design was based on the mathematical calculations with modifications to fit the desired output.  The design was also validated through quality testing of thermal stress, parametric testing, as well as testing for electromagnetic compatibility (EMC) and power dissipation.