Receiver coil for 7-V wireless charging circuitry in distribution

November 29, 2013 // By Graham Prophet
A powdered-iron-based, WPC-compliant (Wireless Power Consortium) wireless charging receiving coil is optimised for use with or without an alignment magnet. Made by Vishay, it is available at distributor Rutronik.

Offering a durable construction and high permeability shielding, the IWAS-4832EC-50 provides high efficiency greater than 75% for the wireless charging of 7-V portable electronics. For higher voltage wireless power base stations and receivers, the high-saturation powdered iron of the IWAS-4832EC-50 is not affected by permanent locating magnets, and the device blocks charging flux from sensitive components or batteries.

As an alternative to ferrite-based solutions, which can saturate in presence of a strong magnetic field, the IWAS-4832EC-50 has magnetic saturation of 50% of inductance at 4000 Gauss. The RoHS-compliant device features inductance of 16.2 µH at 200 kHz with a ±5% inductance tolerance, DCR of 366 mOhm at +25°C, and Q of 30 min. at 200 kHz. It comes with a lead length of 50 mm and tinned length of 10 mm.