Planar Transformers offer the following advantages over traditional transformers:

Low-profile

The use of copper foil lead frames and ‘flat’ ferrite cores means that transformers no longer need to be the bulky 3-D shape that traditional wire-wound transformers necessitated.

Lightweight

Planar transformers offer significant weight advantage, often being 10 times lighter than their wire-wound equivalents. Much of this weight advantage is gained from the very low profile, modern ferrite cores used in planar designs. The ferrite cores are naturally much lighter than the solid iron cores used in traditional wire-wound equivalents A reduction in the amount of copper required for the copper foil lead frames also reduces the weight.

Efficient Inductance

The majority of the losses incurred in the windings of a high frequency transformer are due to AC resistance, as opposed to DC resistance. Planar technology provides a significant reduction in these AC resistance loses, when compared to conventional wire-wound equivalents, and hence results in greater efficiency in the transformer.

Highly Efficient Cooling

The large surface area to volume ratio offered by the flatter cores used in planar transformers makes them ideal for heatsink mounting and forced air-cooling. These heat removal benefits again add greatly to the overall efficiency of the transformer.

Low Leakage Inductance

The laminar construction enables the magnetic coupling between windings to be very good, this in turn results in much lower leakage inductance values.

Unrivalled Repeatability

Planar components are made from pre-formed assemblies, thus the assembly process itself has only a few stages. This simplification of assembly allows planar transformers to be manufactured with very high repeatability and with increased accuracy.

Dimensional Accuracy

The high level of dimensional accuracy of multi-layered printed circuits assures a narrower spread of leakage inductance and winding capacitance. This enables snubbing components to be more precisely specified and the associated losses to be minimized. These are becoming important parameters in the design of modern power converters which use ZVS or ZCS (Zero Voltage Switching / Zero Current Switching).

Multiple Windings Options

Due to the simplified manufacturing process of planar transformers; the windings ratios can easily be amended to suit specific design requirements throughout a production cycle. This not only allows for flexibility in the design, but also reduces costs and time should design alterations be required.

Multiple Topologies

Planar transformers can be applied to any desired switch mode power supply windings topology. In particular the manufacturing process for planar transformers allows for considerably easier transitions between topologies than attainable with traditional technology.

Customized Pin Positions

Uniquely in the market place, Himag Solutions planar transformers do not require a bobbin; therefore non-standard pin pitches can be easily incorporated into any design. Conventionally, when the number of winding terminations exceeds that of the number of bobbin pins, a larger core and bobbin size would be required; leading to under utilisation and increased costs.

Ideal Components

Planar components are electrically closer to an ‘ideal’ component than conventional technologies. This results in better performance due to a reduction in the detrimental effects on the circuit, when compared to their wire-wound counterparts.