This efficient 18V 2A power adapter employs an isolated-flyback power-supply controller that provides Constant-Voltage (CV) using an optical coupler to improve transient response to large-load steps. The 18V adatper processes information from opto-coupled feedback and an auxiliary flyback winding for high-performance control of output voltage and current. The output voltage is regulated accurately by a high-performance voltage-mode amplifier with an accurate voltage reference. The switching adapter meets all green energy initiatives and enables excellent energy efficiency performance with compact profile. The flypower switching adapter offers a wide range of safety features including over-current protection, over-load protection, short-circuit protection to enhance reliability. Equipped with Effective thermal management, the 18V adapter is designed to a MTBF better than 40000 hours at 25℃ with full load. The 18V power adapter series is safety certified to IEC/UL/CSA/EN/RCM/J 60950-1 and carries the CE mark for the Low Voltage and RoHS Directives. The switching adapter PSE is also compliant to EN 55022-B and FCC Class B for radiated and conducted emissions and the IEC 61000-4 immunity and IEC 61000-3-2 harmonic current standards.