Datasheet LTC4125 (Analog Devices)

LTC4125 5W AutoResonant Wireless Power Transmitter
FeaTures DescripTion
n
Monolithic 5W Wireless Power Transmitter
The LTC®4125 is a simple and high performance monolithic n
AutoResonant
TM
Switching Frequency Adjusts to Res-
full bridge resonant driver capable of delivering over 5W of
onant Capacitance and Transmit Coil Inductance*
power wirelessly to a properly tuned receiver. The device n
Transmit Power Automatically Adjusts to Receiver
controls the current flow in a series connected transmit coil
Load*
LC network to create a simple, safe and versatile wireless n
Input Voltage Range: 3V to 5.5V
power transmitter. n
Integrated 100mΩ Full Bridge Switches
The LTC4125 automatically adjusts its driving frequency n
Multiple Foreign Object Detection Methods
to match the LC network resonant frequency. This n Programmable Average Input Current Limit and AutoResonant switching allows the device to deliver Monitor maximum power from a low voltage input supply (3V to n NTC Input for System/Component Temperature 5.5V) to a tuned receiver. To optimize system efficiency, Qualified Power Transfer the LTC4125 employs a periodic transmit power search n Wide Operating Switching Frequency Range: and adjusts the transmission power based on the receiver 50kHz to 250kHz load requirements. The device stops delivering power n Thermally Enhanced 4mm × 5mm QFN 20-Lead Package during a fault condition, or if a foreign object is detected. The LTC4125 also includes a programmable maximum
applicaTions
average input current limit and an NTC input as additional n means for foreign object and overload protection. The Hermetically and/or Electrically Insulated Devices n LTC4125 is available in a 20-lead low profile (0.75mm) Military Sensors and Devices n 4mm × 5mm QFN package. Medical Equipment n Industrial Handhelds L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and AutoResonant is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 9041254. *The AutoResonant and Auto Load Detect features use patent pending circuits and algorithms.
Typical applicaTion 5W Wireless Transmitter
V 20mΩ IN 3V TO 5.5V LTX LRX 2.21k COIL COIL 1µF 100µF 10k IN IN1 IN2 TRANSMITTER RECEIVER STAT NTC CIRCUIT CIRCUIT V + RL IS– SW1 IN – 10nF 11.3k 10k LTX AIR GAP IS+ 24µH CTX V 100nF IN EN LTC4125 SW2 100k FTH VIN 59.0k 100k PTHM FB CFB1 0.1µF IMON CTD CTS GND 5.23k 10nF 348k 470pF 4.7nF 4125 TA01 4125f For more information www.linear.com/LTC4125 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts