Compact transformers sense current up to 20 Amps

Louise Smyth

Nick Flaherty reports on a new range of  transformers designed for use in switching power supplies and overload/short-circuit protection

Coilcraft has developed a series of surface mount current sense transformers which measure just 5.2 X 7.0mm (with a max height of 3.0mm) and sense up to 20Amps of current at frequencies between 10kHz and 1MHz.

Typical applications include load current measurement and control in switching power supplies and overload/short-circuit protection.

The CST7030 series are also qualified to AEC-Q200 Grade 1 (-40°C to +125°C) standards, making them suitable for conventional vehicle and xEV (EV, HEV, FCEV) applications such as current measurement in traction motors and battery management systems. They are also well suited for use in 48V vehicle systems.

The CST7030 Series is available with five turns ratios (primary-to-secondary) ranging from 1:20 to 1:150. It offers very low primary DC resistance (0.0015 Ohms) and 500 Vrms, one minute isolation (hipot) between windings. Coilcraft also offers a high-isolation (1,500 Vdc) version with its CU8965-AL Series.

CST7030 Series current sense transformers feature RoHS compliant tin-silver, over tin, over nickel, over phosphor bronze terminations and have a maximum reflow temperature of 260°C.