LM3269

Product Folder Sample & Buy Technical Documents Tools & Software Support & Community LM3269 SNVS793D – NOVEMBER 2011 – REVISED MAY 2015 LM3269 Seamless-Transition Buck-Boost Converter for 3G and 4G RF Power Amplifiers 1 Features 1 Operates From a Single Li-Ion Cell: 2.7 V to 5.5 V Adjustable Output Voltage: 0.6 V to 4.2 V Automatic PFM or PWM Mode Change 750-mA Maximum Load Capability for VBATT ≥ 3 V, VOUT = 3.8 V 2.4-MHz (typical) Switching Frequency Seamless Buck-Boost Mode Transition Fast Output Voltage Transition: 1.4 V to 3 V in 10 µs High-Efficiency: 95% typical at VBATT = 3.7 V, VOUT = 3.3 V, at 300 mA Input Overcurrent Limit Internal Compensation 2 Applications Power Supply for 3G/4G Power Amplifiers Cellular Phones Portable Hard Disk Drives PDAs 3 Description The LM3269 is buck-boost DC-DC converter designed to generate output voltages above or below a given input voltage and is particularly suitable for portable applications powered by a single-cell Li-ion battery. The LM3269 operates at a 2.4-MHz typical switching frequency in full synchronous operation and provides seamless transitions between buck and boost operating regimes. The LM3269 operates in energysaving Pulse Frequency Modulation (PFM) mode for increased efficiencies and current savings during lowpower RF transmission modes. The power converter topology needs only one inductor and two capacitors. A unique internal power switch topology enables high overall efficiency. The...