1FEATURES
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 Smart-
phones 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 maximum
current load of 2.5A.
The LM3248 is available in a 30-bump, lead-free thin
DSBGA package.