LM3279 Buck-Boost Converter Datasheet

LM3279 Datasheet, PDF, Equivalent


Part Number

LM3279

Description

Buck-Boost Converter

Manufacture

etcTI

Total Page 30 Pages
Datasheet
Download LM3279 Datasheet


LM3279
Product
Folder
Sample &
Buy
Technical
Documents
Tools &
Software
Support &
Community
LM3279
SNVS970C – MARCH 2013 – REVISED OCTOBER 2014
LM3279 Buck-Boost Converter With MIPI® RFFE Interface
for 3G And 4G RF Power Amplifiers
1 Features
1 MIPI® RFFE Digital Control Interface
• High-Efficiency PFM and PWM Modes with
Internal Seamless Transition
• Operates from a Single Li-Ion Cell: 2.7 V to 5.5 V
• Adjustable Output Voltage:
– RFFE Digital Control: 0.4 V to 4.2 V
– Analog Control: 0.5 V to 4.2 V
• 1-A Maximum Load Capability for VBATT 3.2 V,
VOUT = 3.6 V
• 2.4-MHz (typ.) Switching Frequency
• Seamless Buck-Boost Mode Transition
• Fast Output Voltage Transition: 0.8 V to 4 V in 20
µs
• High-Efficiency: 95% typ. at VBATT = 3.7 V,
VOUT = 3.3 V, at 300 mA
• Input Overcurrent Limit
• Output Overvoltage Clamp
• Internal Compensation
2 Applications
• 3G/4G Smartphones
• RF PC Cards
• Tablets, eBooks Readers
• Battery-Powered RF Devices
Simplified Schematic
1.5 ÛH
VBATT: 2.7V to 5.5V
10 ÛF
SW1
SW2
PVIN
SVIN
VOUT
FB
EN
GPO0
GPO1
DGND
LM3279 VCON
SGND
VIO
SDATA
SCLK
PGND
RF Control
Bits
VOUT: 0.4V to 4.2V
10 ÛF
RF PA(s)
2 x 0.47 ÛF
(PA decoupling caps)
BB or
RFIC
3 Description
The LM3279 is a buck-boost DC/DC converter
designed to generate output voltages above or below
a given input voltage and is particularly suitable for
Power Amplifiers operating from single-cell Li-Ion
batteries in portable applications.
The LM3279 has four modes of operation: Pulse
Width Modulation (PWM), Pulse Frequency
Modulation (PFM), standby, and shutdown. During
normal conditions, the LM3279 operates in full
synchronous PWM mode at 2.4-MHz typical switching
frequency, providing seamless transitions between
buck and boost operating regimes. Energy-saving
PFM mode increases efficiencies and current savings
during low-power RF transmission modes. For high-
transmit power, the device operates in PWM buck or
boost mode, whereas the device can transition
between PWM and PFM modes during low-power
transmit. The LM3279 can be controlled either via an
included MIPI RFFE Digital Control Interface or by
using an analog control from an external MCU,
offering design flexibility.
The power converter topology enables minimum total
solution size by using one small footprint and case
size inductor and two surface mount capacitors.
The LM3279 is internally compensated for buck and
boost modes of operation thus providing an optimal
transient response.
Device Information(1)
PART NUMBER
PACKAGE
BODY SIZE (MAX)
LM3279
DSBGA (16)
2.529 mm x 2.146 mm
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
PWM Efficiency (VOUT = 2.4 V)
100
90
80
70
60
PVIN = 2.7V
PVIN = 3.0V
50 PVIN = 3.6V
PVIN = 4.2V
40
0
100 200 300 400 500 600 700
OUTPUT LOAD (mA)
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.

LM3279
LM3279
SNVS970C – MARCH 2013 – REVISED OCTOBER 2014
www.ti.com
Table of Contents
1 Features .................................................................. 1
2 Applications ........................................................... 1
3 Description ............................................................. 1
4 Revision History..................................................... 2
5 Pin Configuration and Functions ......................... 3
6 Specifications......................................................... 4
6.1 Absolute Maximum Ratings ...................................... 4
6.2 Handling Ratings ...................................................... 4
6.3 Recommended Operating Conditions....................... 4
6.4 Thermal Information .................................................. 5
6.5 Electrical Characteristics........................................... 5
6.6 System Characteristics ............................................ 6
6.7 System Characteristics Recommended Capacitance
Specifications ............................................................. 7
6.8 Typical Performance Characteristics ....................... 9
7 Detailed Description ............................................ 12
7.1 Overview ................................................................. 12
7.2 Functional Block Diagram ....................................... 13
7.3 Feature Description................................................. 13
7.4 Device Functional Modes........................................ 15
7.5 Programming........................................................... 16
7.6 Registers ................................................................. 19
8 Application and Implementation ........................ 21
8.1 Application Information............................................ 21
8.2 Typical Application ................................................. 21
9 Power Supply Recommendations...................... 24
10 Layout................................................................... 25
10.1 Layout Guidelines ................................................. 25
10.2 Layout Examples................................................... 26
10.3 DSBGA Package Assembly And Use ................... 30
10.4 Manufacturing Considerations .............................. 30
11 Device and Documentation Support ................. 31
11.1 Device Support .................................................... 31
11.2 Documentation Support ....................................... 31
11.3 Trademarks ........................................................... 31
11.4 Electrostatic Discharge Caution ............................ 31
11.5 Glossary ................................................................ 31
12 Mechanical, Packaging, and Orderable
Information ........................................................... 31
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision B (November 2013) to Revision C
Page
• Added Device Information and Handling Rating tables, Feature Description, Device Functional Modes, Application
and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support, and
Mechanical, Packaging, and Orderable Information sections; moved some curves to Application Curves section .............. 1
Changes from Revision A (May 2013) to Revision B
Page
• Changed Analog control 0.6V to 0.5V .................................................................................................................................... 1
• Changed 0.2V VCON 1.4V to 0.167V VCON 1.4V .................................................................................................... 6
• Changed 0.2 V to 0.167 V ...................................................................................................................................................... 6
• Changed 0.6 V to 3.4 V to 1.6 V to 3.4 V............................................................................................................................... 7
• Changed 200 from max. to typ. .............................................................................................................................................. 7
• Changed 0.2V (min.) to 1.4V (max. typ.) to 0.167V (min.) to 1.4V (max. typ.); from 0.6V to 4.2V output to from 0.5V
to 4.2V output ....................................................................................................................................................................... 14
• Added (default) ..................................................................................................................................................................... 19
• Added (default) ..................................................................................................................................................................... 19
2 Submit Documentation Feedback
Product Folder Links: LM3279
Copyright © 2013–2014, Texas Instruments Incorporated


Features Product Folder Sample & Buy Technical Documents Tools & Software Support & Community LM3279 SNVS970C – MARCH 20 13 – REVISED OCTOBER 2014 LM3279 Buck -Boost Converter With MIPI® RFFE Inter face for 3G And 4G RF Power Amplifiers 1 Features •1 MIPI® RFFE Digital Co ntrol Interface • High-Efficiency PFM and PWM Modes with Internal Seamless T ransition • Operates from a Single Li -Ion Cell: 2.7 V to 5.5 V • Adjustabl e Output Voltage: – RFFE Digital Cont rol: 0.4 V to 4.2 V – Analog Control: 0.5 V to 4.2 V • 1-A Maximum Load Ca pability for VBATT ≥ 3.2 V, VOUT = 3. 6 V • 2.4-MHz (typ.) Switching Freque ncy • Seamless Buck-Boost Mode Transi tion • Fast Output Voltage Transition : 0.8 V to 4 V in 20 µs • High-Effic iency: 95% typ. at VBATT = 3.7 V, VOUT = 3.3 V, at 300 mA • Input Overcurren t Limit • Output Overvoltage Clamp Internal Compensation 2 Applications • 3G/4G Smartphones • RF PC Cards Tablets, eBooks Readers • Battery-Powered RF Devices Simplified Schematic 1.5 ÛH VBATT: 2.7V to 5.5V .
Keywords LM3279, datasheet, pdf, etcTI, Buck-Boost, Converter, M3279, 3279, 279, LM327, 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)