A single-phase transformer is one where both the primary and secondary windings are single-phase windings.

Single-polarity switch mode power supply, referring to an output that is single-polarity, meaning only positive and negative poles are provided. Compared to bipolar switch mode power supplies, which have three outputs: positive power, negative power, and ground.

Single-phase transformers have a simple structure, small size, and low losses, primarily due to their minimal iron losses. They are suitable for application and promotion in low-voltage distribution networks with low load density.