AS1345 18V, High Efficiency, DC-DC Step-Up Converter The AS1345 high efficiency DC-DC step-up converter contains General Description an internal N-channel and an internal P-channel output isolation switch. The device operates from a 2.9V to 5.0V supply and can boost voltages up to 18V. A hysteretic control scheme is used to provide the highest operating efficiency over a wide range of input and output load conditions. The internal MOSFET switches reduce the external component count and a high switching frequency allows the use of tiny surface mount components. The AS1345 employ a factory set current limit to reduce ripple and external component size in low output current applications. With a 500mA current limit the AS1345 is capable of providing 20mA 18V output. Figure AS1345 1: Available Products Devices Peak Coil Current Output AS1345A 100mA adjustable or fixed AS1345B 200mA adjustable or fixed AS1345C 350mA adjustable or fixed AS1345D 500mA adjustable or fixed For order related information, please refer to Ordering Information on page 24. Built-in safety features protect the internal switches and output components from fault conditions. Additional power-saving attributes include a very low quiescent current and a true shutdown mode. Figure AS1345 2: Key Benefits and Features Benefits Features Supports Lithium primary and re-chargeable Input Voltage Range: 2.9V to 5.0V batteries Supports a variety of end applications Adjustable Output Voltage Range: 5.0V to 18V 18V, High Efficiency, DC-DC Step-Up Converter AS1345 1Benefits Features Supports a variety of end applications Output Current up to 40mA Allows optimization of circuit depending on output Inductor Peak Currents: 100, 200, 350 and 500 mA power demands Battery life improved 90% Efficiency Battery supply isolated during shutdown True Shutdown Fault tolerant Short Circuit and Thermal Protection Packages: 8-pin (2x2mm) TDFN Small chipscale package 8-bumps (1.570mm x 0.895mm) WL-CSP with 0.4mm pitch The AS1345 is ideal for small and low current demand LCD Applications panels, as well as for polymer LEDs (OLED), cell phones, PDAs, readers, mobile terminals and 3D shutter glasses. Figure AS1345 3: Typical Application Diagram 10uF 10uH to 22uH SWIN SWOUT VDD = 2.9V to 5.0V Vout = 5.0V to 18V VDD LX 47pF R2 AS1345 10uF 100k POK FB 1uF to 10uF R3 ON EN GND OFF AS1345 2 18V, High Efficiency, DC-DC Step-Up Converter