LTC4125 Datasheet | Linear Technology

5W Auto Resonant Wireless Power Transmitter Features nn Monolithic 5W Wireless Power Transmitter nn Auto Resonant TM Switching Frequency Adjusts to Res- onant Capacitance and Transmit Coil Inductance- nn Transmit Power Automatically Adjusts to Receiver Load- nn Input Voltage Range: 3V to 5.5V nn Integrated 100mΩ Full Bridge Switches nn Multiple Foreign Object Detection Methods nn Programmable Average Input Current Limit and Monitor nn NTC Input for System/ponent Temperature Qualified Power Transfer nn Wide Operating Switching Frequency Range: 50k Hz to 250k Hz nn Thermally Enhanced 4mm × 5mm QFN 20-Lead Package Applications nn Hermetically and/or Electrically Insulated Devices nn Military Sensors and Devices nn Medical Equipment nn Industrial Handhelds Description The LTC®4125 is a simple and high performance monolithic full bridge resonant driver capable of delivering over 5W of power wirelessly to a properly tuned receiver. The device controls the current flow in a series connected transmit coil LC network to create a simple, safe and versatile wireless power transmitter. The LTC4125 automatically adjusts its driving frequency to match the LC network resonant frequency. This Auto Resonant switching allows the device to deliver maximum power from a low voltage input supply (3V to 5.5V) to a tuned receiver. To optimize system efficiency, the LTC4125 employs a periodic transmit power search and adjusts the transmission power based on the receiver load requirements. The device stops delivering power during a fault condition, or if a foreign object is detected. The LTC4125 also includes a programmable maximum average input current limit and an NTC input as additional means for foreign object and overload protection. The LTC4125 is available in a 20-lead low profile (0.75mm) 4mm × 5mm QFN package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Auto Resonant is a trademark of Linear Technology Corporation. All other...