LTC3421 Datasheet | Linear Technology

3A, 3MHz Micropower Synchronous Boost Converter with Output Disconnect Features nn Synchronous Rectification: Up to 96% Efficiency nn True Output Disconnect nn Inrush Current Limiting nn Very Low Quiescent Current: 12µA nn Up to 1.5A Continuous Output Current nn Fixed Frequency Operation Up to 3MHz nn 0.5V to 4.5V Input Range nn 2.4V to 5.25V Adjustable Output Voltage nn Guaranteed 1V Start-Up nn Programmable Current Limit nn Programmable Soft-Start nn Synchronizable Oscillator nn Manual or Automatic Burst Mode® Operation nn Low-Battery parator nn <1µA Shutdown Current nn 1.22V Reference Output Voltage nn Small (4mm × 4mm) Thermally Enhanced QFN Package APPLICATIONS nn Handheld puters nn Cordless Phones nn GPS Receivers nn Battery Backup Supplies DESCRIPTION The LTC®3421 is a high efficiency, current mode, fixed frequency, step-up DC/DC converter with true output disconnect and inrush current limiting. The device includes a 0.10Ω N‑channel MOSFET switch and a 0.14Ω P-channel synchronous rectifier. This product has the ability to simply program the output voltage, switching frequency, current limit, soft-start, Burst Mode threshold and loop pensation with external passive ponents. Quiescent current is only 12µA during Burst Mode operation, maximizing battery life in portable applications. The oscillator frequency can be programmed up to 3MHz and can be synchronized to an external clock applied to the SYNC pin. An open-drain unmitted low-battery parator is included. The part maintains operation in applications with a secondary cell powering the output voltage during shutdown. Other Features include: 1µA shutdown, antiringing control, thermal limit and reference output. The LTC3421 is available in a small 4mm × 4mm QFN package. All registered trademarks and trademarks are the property of their respective owners. TYPICAL APPLICATION VIN 1.8V TO 3V 4.7µH 2 CELLS 4.7µF 4 SHDN ENB 3 VREF 23 LBI 22 LBO 7 SYNC 8 ILIM 45.3k SS RT 21 14...