Ferrite cores enable increased power density

Designers can now downsize power supplies whilst at the same time increasing power density. Air gapped cores are typically made to special order or are application specific.

TDK has developed a range of distributed air gap (DG) ferrite cores using their highly automated production processes which has resulted in them being able to offer a standardised and cost-effective range of DG products.

Distributed air gap (DG) ferrite cores allow the design of transformers and chokes with significantly increased power density and reduction of losses caused by the proximity effect and eddy currents within the cores, these cores offer improved thermal performance with temperature stability up to 180°C optimising the design of the PCB magnetics.

The cores utilise three identical sized air gaps, TDK has calculated this configuration offers the best cost performance ratio, these cores offer an enlarged winding area, larger fill factor and decreases fringing flux losses by 70%.

Using these DG cores designers are able to achieve higher thermal performance using solid wires, they can achieve similar high frequency performance to more expensive litz wire but with a better R_DC. 

The cores can be used in the design of LLC Transformers, Resonance & Storage Chokes, Flyback Transformers, PFC Choles for active PFC's in Boundary (BCM), Critical (CrCM) and Discontinuous (DCM) Conduction modes and general power conversion in applications where a larger air gap is required.

The standardised range of DG cores are available in standard geometries E, ETD, and PQ cores in a wide range of sizes and power materials N87, N95 and N97, and cover an inductance factor range between 60 nH and 400 nH. The DG cores are compatible with TDK's broad portfolio of accessories including coil formers and mounting hardware.

Ferrite cores with distributed air gaps can be used in a wide range of automotive and industrial applications such as EV charging stations, on-board chargers and DC-DC converters, solar inverters, UPS, industrial SMPS as well as telecom and server SMPS.

Anglia are offering customers free samples of the distributed air gap ferrite cores from TDK.