LM3248 Datasheet, PDF (1/31 Pages) Texas Instruments – LM3248 2.7 MHz, 2.5A Adjustable Boost-Buck DC/DC Converter

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
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•2 Output Voltage V_OUT Adjustable from 0.4V to
4.0V (typ.)
• Input Voltage Range V_IN 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 V_IN
range of 2.7V to 5.5V and an adjustable output
voltage V_OUT 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.
Typical Application Diagram
1.0 H
10 F
1 F Low ESL
VBATT
2.7V to 5.5V
10 F
SW_
BOOST
OUT_
BOOST
PVIN_
BOOST
VDD_
BOOST
BYPASS
BOOST
PVIN_
BUCK
VDD1_
BUCK
VDD2_
BUCK
FB_
BUCK
ACB
BUCK
ACB
SW_
BUCK
1.5 H
10 F
CONTROL
SGND_
BOOST_
SGND_
BOOST ^{DGND ENABLE GATE MODE BUCK}
VCON
FB
1 nF
VCC_PA
Apps
Processor
1.8V Logic
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2013, Texas Instruments Incorporated