About DC-DC Power Supply suppliers

DC allows constant current to flow to the device. Since alternating current is initially provided, the power source must first be converted from alternating current to direct current. Most smaller electronic devices, such as computers, require DC power to work with AC-DC converters from wall power.

AC-DC Conversion Basics
電源装置は、壁のコンセントから AC 電源を取得し、それを調整されていない DC 電源に変換し、入力電源トランスを使用して、通常は負荷が必要とする電圧まで電圧を下げます。安全上の理由から、変圧器は出力電力を主電源入力から分離します。

There are two types of AC power sources, unregulated and regulated. Unregulated power supplies are the most basic type of power supply and cannot provide a consistent voltage to the load, while regulated power supplies have and have many different design options.

Linear converters are the simplest, but also generate the most heat, while switching converters are more complex and cooler, but generate more noise. Batteries are usually switching converters. Each has advantages and disadvantages, but which one to use depends largely on the type of application and the conditions under which it is run.