9V AC to DC Wall Adapter, 9W/ 18W, 1A/ 2A

9V wall mount AC adapter with cheap price, which features frequency 50-60Hz, 100-250VDC input voltage, DC port size 5.5*2.5mm (compatible 5.5*2.1mm). The wall plug adapter has the advantages of good flexibility, fast charging speed, environmental protection, non-toxicity, good flexibility, and durability.

Specification

Dimension (mm)

Tips: How to Solve the Electromagnetic Compatibility of AC Wall Adapter?

The single-stage EMI filter of the wall adapter power supply mainly includes common mode chokes and filter capacitors. The EMI filter can effectively suppress the electromagnetic interference of the switching power adapter. Using soft switching start technology, adding inductance to the original hard switching circuit And capacitive elements, using the resonance of capacitance and inductance to reduce du/dt and di/dt during the switching process, so that the voltage drop when the switching device is turned on is before the timing of the rise of the current, or the current drop is before the voltage when the switching device is turned off. The timing of the rise of the voltage and current to eliminate the overlap of voltage and current. Reasonable use of electromagnetic interference filters, one of the main purposes of EMI filters, power grid noise is a type of electromagnetic interference, which belongs to radio frequency interference, and the frequency spectrum of its conducted noise is roughly 10KHz~30MHz, up to 150MHz. In general, the differential mode interference amplitude is small and the frequency is low, and the interference caused is small, the common mode interference amplitude is large, the frequency is high, and radiation can be generated through the wire, which causes greater interference.