This wall mounted 12V 2A power adapter provides a high-power-density and cost-effective solution for a variety of application field. The power adapter 12V 2A operates at a high switching frequency to achieve high efficiency in all load conditions, with an extremely low total standby consumption and low output ripple and nose. The 12V 2A ac/dc power adapter full protection functions to improve the reliability including OCP, OVP, OLP to prevent the circuit from being damaged in abnormal conditions. Effective thermal management enhances reliability further, allows the ac dc adapter 12V 2A to operate at full power at higher ambient temperatures.