AutoResonant wireless power transmitter offers foreign object detection

AutoResonant wireless power transmitter offers foreign object detection

Linear Technology has introduced the LTC4125, a wireless power transmitter, complementing its wireless receiver ICs for the wireless charging market. The LTC4125 is a monolithic full bridge resonant driver, capable of delivering up to 5W of power wirelessly to a companion receiver.

The LTC4125 is claimed to improve upon basic transmitters thanks to an AutoResonant function that is said to maximise receiver power; an Optimum Power Search algorithm that maximises overall wireless power system efficiency; and Foreign Object Detection to ensure safe and reliable operation when working in the presence of conductive foreign objects.

The LTC4125 is said to automatically adjust its drive frequency to match the LC network resonant frequency. AutoResonant switching is claimed to enable the device to deliver maximum power from a low voltage input supply to a tuned receiver such as Linear’s LTC4120 wireless receiver and battery charger via loosely coupled coils.

Applications include handheld instruments, industrial/military sensors and similar devices in harsh environments, portable medical devices, and electrically isolated devices. LTC4125-based systems are said to offer robust, standalone solutions, capable of transmission distances up to 10mm and tolerance of poor coil coupling due to misalignment.

The LTC4125 is housed in a 20-pin 0.75 x 4 x 5mm QFN package with backside metal pad for thermal performance. The device is specified for operation from -40 to 125°C, in both E and I grades.

Categories: News, Power, Wireless