LM3248

LM3248 www.ti.com SNVSA01A – JULY 2013 – REVISED SEPTEMBER 2013 LM3248 2.7 MHz, 2.5A Adjustable Boost-Buck DC/DC Converter with Boost and Active Current Assist and Analog Bypass (ACB) Check for Samples: LM3248 FEATURES 1 2 Output Voltage VOUT Adjustable from 0.4V to 4.0V (typ.) Input Voltage Range VIN from 2.7V to 5.5V Boost-Buck and Buck (Boost-Bypass) Operating Modes with Seamless Transition 2.5A Load Current Capability High Conversion Efficiency (> 90% typ.) High-Efficiency PFM/PWM Modes with Seamless Transition Very Fast Transient Response: 10 µs ACB Reduces Inductor Size Requirements Dither to aid RX Band Noise Compliance APPLICATIONS Multi-mode 2G/3G/4G and 3GPP/LTE Smartphones and Tablets Hand-Held Radios RF Mobile Devices DESCRIPTION The LM3248 is a PWM/PFM Boost-Buck DC/DC converter that provides efficient utilization of battery power over a wide voltage range. The device architecture is suitable for advanced RF front-end systems that demand dynamic voltage and current to support converged power amplifier architectures operating in 2G/3G/4G and 3GPP/LTE modes. For example, the LM3248 is designed to produce higher output voltages while maintaining PFM mode as required by some new reduced-power CMOS PAs. The extremely fast Boost-Buck function reduces RF PA overhead power dissipation, extending battery talk time. The device will operate at input voltage VIN range of 2.7V to 5.5V and an adjustable output voltage VOUT range of 0.4V to 4.0V at a...