Wireless power charging coils pair with TI silicon, offer Qi compatibility

February 20, 2014 // By Graham Prophet
Würth Elektronik eiSos has added three new wireless power charging coils to its range. They have a self-adhesive film on the back to simplify assembly.

The coils have flexible ferrite shielding and are extremely thin at only 1 mm. The thin and flexible carrier material is suited for the suppression of interference above 1MHz. The coils have a high Q-factor and very low DC resistance, for maximum efficiency power transfer of up to 5W.

Further wireless power transfer coils, for both the transmitter and receiver sides, will be added.

All charging coils have been evaluated and approved with chipsets from Texas Instruments and are Qi compliant. Würth Elektronik eiSos is member of the “Wireless Power Consortium” and of the “Alliance for Wireless Power” (A4WP).

The coils are, respectively, 48 x 32 x 0.95mm with inductance of 12 μH, Q-Factor of 33, for 5V operation and with a connector length of 15mm; 48 x 32 x 0.86mm with inductance of 12 μH, Q-Factor of 21, for operation at 5V and with connector length of 15mm; and 38.5 x 30.5 x 0.87mm with inductance of 16.7μH, Q-Factor of 40, for operation at 7V and with connector length of 15mm.

Wurth Electronics Midcom; www.we-online.com