Compact SMT 30 A Current Transformer – PH9494 Series

     Pulse Electronics has expanded its range of surface mount current transformers (CSTs). The 13 mm x 10 mm x 7.2 mm EE8 platform extends the current carrying capability of miniature CST products to 30 A, enabling a very low DCR (0.35 mOhm max) single-turn primary winding. The family includes a variety of secondary winding configurations to achieve primary to secondary turns ratios from 1:50 to 1:200.

     Current transformers provide isolation between sensitive control circuits and the higher power rails being measured. They are a cost-effective and low-loss method for measuring current in high-frequency regulators and switch-mode power supplies. The current to be sensed is passed through a single-turn low-resistance primary winding, which generates a magnetic field within the element's magnetic core. This magnetic field is then coupled to the high turns secondary winding, resulting in a lower current proportional to the turns ratio. Safe isolation is achieved because there is no electrical connection between the primary and secondary.