What Is a Switching Transformer?
A Switching Transformer is an essential component in power supplies, particularly in the predominant Switching Power Supplies.
Switching Power Supplies generate a pseudo-high-frequency alternating current internally, achieving compact and highly efficient power conversion and transmission through high-frequency operations.
Optimizing the transformer allows for the design of a power supply with minimal heat generation and noise. It stands as the most crucial component in the construction of Switching Power Supplies.
Uses of Switching Transformer
Switching Transformers are used, as the name suggests, in Switching Power Supplies.
Since Switching Power Supplies are employed in various electrical products, Switching Transformers find application in a wide range of electrical devices.
These include household appliances such as TVs, and air conditioners, communication devices like routers and gateways, information equipment like photocopiers and computers, industrial machinery like semiconductor manufacturing equipment, processing equipment, robots, and more.
Principles of Switching Transformer
Similar to other transformers, a Switching Transformer converts electrical energy into magnetic energy and facilitates the transmission of power.
The transferred magnetic energy is then reconverted into electrical energy to supply power to electronic devices. By increasing the frequency, transformers can be made smaller.
In addition to power transmission, Switching Transformers also incorporate a protective function (isolation) by interrupting unnecessary power to ensure the safe use of electronic products.
Concerning core materials, as power conversion occurs at high frequencies, suitable magnetic materials for rapidly changing magnetic flux are needed. Depending on the frequency band, magnetic materials like ferrite and dust are used selectively, with ferrite being commonly used in Switching Power Supplies.
How to Choose Switching Transformer
To match the Switching Transformer with the intended Switching Power Supply, the transformer must be custom-designed.
As this process can be quite complex and challenging, it usually involves discussions with the transformer manufacturer to finalize the design. The following steps are summarized in a flowchart style:
- Determine the specifications of the power supply (input/output voltage, output power, circuit configuration, selection of control IC, oscillation frequency).
- Choose the desired transformer shape from the transformer manufacturer’s catalog.
- Size depends on the circuit configuration and oscillation frequency, so consultation with the manufacturer to decide is advisable.
- When high insulation is required, using a larger transformer compared to power requirements is recommended (consult with the manufacturer).
- Regarding pin assignment, constraints exist based on the layout of the circuit board and manufacturing constraints for the transformer. Consultation with the manufacturer is necessary for decision-making.
Furthermore, applicable safety standards vary depending on the destination and application. Transformers need to be designed to comply with these standards.
Since transformers are highly customized components, discussing with the manufacturer during the conceptual stage is advisable. Achieving optimization involves repeated prototyping and verification.
Finding a manufacturer with whom discussions are easy is a shortcut to optimal design.