If you mean ‘not a switching power supply’ here is my take. A switcher takes rectified ac and pluse width modulates it into voltage regulated DC. This thing just changes DC to ac.

The most common type of power supply today is the switching supply. These units use pulse-width modulation (PWM) to regulate output. Supplies today employ several different PWM circuit configurations.

Switch mode power supplies aren’t new ideas, either, and surprisingly pre-date the first commercially-available transistor although modern ones like these are much less expensive to build.

Major players in the switch mode power supply transformers market are ABB Group, APX Inc., Infineon Technologies AG, Omron Corporation, Premier Magnetics, Salcomp PLC, Schneider Electric SE ...

Several semiconductor component suppliers offer design tools to help design switch mode power supplies, such as WEBENCH Power Designer from Texas Instruments (figure 4). Below, figure 4: The opening ...

Although HLK is a great power supply module for IoT and DIY projects, especially because of its compact size and low cost, the 3.3-V version is not as easy to find compared to the 5-V (and 12-V) ...