LM3248 DC/DC Converter Datasheet

LM3248 Datasheet, PDF, Equivalent


Part Number

LM3248

Description

2.5A Adjustable Boost-Buck DC/DC Converter

Manufacture

etcTI

Total Page 30 Pages
Datasheet
Download LM3248 Datasheet


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 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.
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
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
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

LM3248
LM3248
SNVSA01A – JULY 2013 – REVISED SEPTEMBER 2013
www.ti.com
DESCRIPTION (CONTINUED)
The LM3248 utilizes step-up (Boost) and variable output step-down (Buck) DC/DC converters. Combining a
cascaded Boost and Buck converter in a single package is ideal for powering the latest multimode/multi-standard
RF power amplifiers. The Boost converter provides the RF power subsystem the capability to operate at lower
battery voltages as well as to maintain increased PA linearity and transmit power margins over a wider battery
voltage supply range.
The Buck has a unique Active Current assist and analog Bypass (ACB) feature to minimize inductor size without
any loss of output regulation for the entire battery voltage and RF output power range, until dropout. ACB
provides a parallel current path, when needed, to limit the maximum inductor current while still driving a 2.5A
load. The LM3248 may also be configured as a Buck-only converter with a boost bypass feature to enable
highest efficiency operation with minimal dropout voltage when the Boost is not needed.
The LM3248 automatically and seamlessly transitions between Pulse Width Modulation (PWM) and Pulse
Frequency Modulation (PFM) modes for high-efficiency operation with both full and light load conditions.
Connection Diagram
A VDD_
BOOST
PVIN_
BOOST
PVIN_
BOOST
OUT_
BOOST
OUT_
BOOST
B BOOST_
GATE
SGND_
BOOST
SW_
BOOST
SW_
BOOST
SW_
BOOST
C MODE
VDD1_
BUCK
SGND_
BUCK
PGND
PGND
D ENABLE
VCON
NC
SW_
BUCK
SW_
BUCK
E ATB1
FB_
BUCK
DGND
PVIN_
BUCK
PVIN_
BUCK
F ATB2
VDD2_
BUCK
BGND
ACB
ACB
1 2 3 45
Figure 1. 30-Bump Thin DSBGA Package (0.4 mm pitch)
(Top View, bumps down)
2 Submit Documentation Feedback
Product Folder Links: LM3248
Copyright © 2013, Texas Instruments Incorporated


Features LM3248 www.ti.com SNVSA01A – JULY 20 13 – REVISED SEPTEMBER 2013 LM3248 2 .7 MHz, 2.5A Adjustable Boost-Buck DC/D C Converter with Boost and Active Curre nt Assist and Analog Bypass (ACB) Check for Samples: LM3248 FEATURES 1 •2 O utput Voltage VOUT Adjustable from 0.4V to 4.0V (typ.) • Input Voltage Range VIN from 2.7V to 5.5V • Boost-Buck a nd Buck (Boost-Bypass) Operating Modes with Seamless Transition • 2.5A Load Current Capability • High Conversion Efficiency (> 90% typ.) • High-Effici ency PFM/PWM Modes with Seamless Transi tion • Very Fast Transient Response: 10 µs • ACB Reduces Inductor Size Re quirements • Dither to aid RX Band No ise Compliance APPLICATIONS • Multi-m ode 2G/3G/4G and 3GPP/LTE Smartphones a nd 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 rang e. The device architecture is suitable for advanced RF front-end systems that demand dynamic.
Keywords LM3248, datasheet, pdf, etcTI, 2.5A, Adjustable, Boost-Buck, DC/DC, Converter, M3248, 3248, 248, LM324, LM32, LM3, Equivalent, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute




@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)