EPCOS Releases Two New Series Of Compact Current Sense Transformers

EPCOS announced that it has developed two series of current sense transformers that – thanks to what is described as their space-saving SMT design – are suitable for compact dc-dc converters. They have dimensions of only 8.33 x 7.11 mm² and 4.7 x 3.5 mm², respectively. The primary winding is already integrated in all types, thus saving development and placement times. Both series cover winding ratios from 1:20 to 1:125.

The first series is said to represent a compatible solution for existing designs based on an EE5 core. The dc resistance of the primary winding is 0.8mΩ and the rated current is 20A for all types of this series. They have a test voltage of 500Vac.

The second series was developed as a miniature variant with the significantly more compact E4.2 core. The primary winding is integrated in the coil former in a space saving way. Its dc resistance is 2.5mΩ and its rated current is 7A. The test voltage of these types is 360Vac.

Current sense transformers are used in control and protection circuits as well as for load detection in power supplies. Typical applications are dc-dc converters for mid-range outputs.