TDK Corporation presents a new series of compact EPCOS SMT current sense transformers. They are designed for measuring currents of up to 7 A at frequencies between 50 kHz and 1 MHz. The B82801A1 series comprises nine types that offer transformation ratios from 1:20 to 1:150 between the primary and secondary winding. The maximum DC resistance of the primary winding for all types is only 2.5 mΩ. Excellent reproducibility and reliability are ensured by highly automated production using laser welding technology.
The compact design of the RoHS-compatible components is particularly noteworthy: The footprint is only 4.5 × 4.85 mm and the height is 3.5 mm. Thanks to the insulating coating of the ferrite cores, a particularly space-saving installation on tightly populated boards is possible. The test voltage of the windings is 500 V. Applications of the new current sense transformers include overload detection and detection of load shedding in switch mode power supplies.