Energy-Harvesting Apps Could Reap Benefits From Mini Step-Up Transformers
Coilcraft’s LPR6235 series of coupled inductors can be used as step-up or flyback transformers in dc-dc converters, or as autotransformers. Their coupling coefficient (k = 0.95) five turns ratio options (1:10 to 1:100) will suit a number of step-up and step-down applications, such as energy harvesting. For example, Linear Technology selected the LPR6235s for its LTC3108 and LTC3109 step converter and power managers. The 6-mm-square by 3.5-mm-high shielded inductors maintain 300-V winding-to-winding isolation, and feature high ISAT and low dc resistance. A smaller LPR4012 series transformer measures 4 mm square by 1.1 mm high. The RoHS-compliant device offers a maximum reflow temperature of 260°C. Terminations consist of silver-palladium-platinum-glass frit. COTS Plus tin-silver-copper and tin-lead terminations also are available.