TI1 LP3974 Product brief high performance power management unit for application processor Datasheet

LP3974
LP3974 PRODUCT BRIEF High Performance Power Management Unit for
Application Processors
Literature Number: SNVS645A
October 19, 2011
High Performance Power Management Unit for Application
Processors
General Description
Features
The LP3974 is designed to meet the power management requirements of the latest cellular phones. The LP3974 PMU
contains a single-input Li-Ion battery charger, 16 low-dropout
voltage regulators (including 5 wide input low-output regulators, 2 over-voltage protected voltage regulators, and 4 buck
regulators), dual DPDT analog switches, real time clock, and
backup battery charger. Programming is handled via an I2Ccompatible high-speed Serial Interface allowing control of
program on/off conditions and the output voltages of individual regulators, and to read status information of the PMU.
It can charge and maintain a single cell Li-Ion battery operating from an AC adapter or USB power source.
The Li-Ion charger requires few external components and integrates the power FET. Charging is thermally regulated to
obtain the most efficient charging rate for a given ambient
temperature.
Over-Voltage Protection (OVP) circuit at the charger input
protects the PMU from input voltages up to +28V, eliminating
the need for any external protection circuitry.
Buck regulators have an automatic switch to ECO mode at
low load conditions providing very good efficiency at low output currents.
General-type LDO regulators provide excellent PSRR and
ULTRA LOW NOISE, 45 μV typ., ideally suited for supplying
voltage to RF section.
The real-time clock/calendar provides time interval information as well as two programmable alarms.
To accommodate different processor requirements, the
LP3974 PMU can have three different default voltage settings
and startup sequences selected by external pin.
Notice: This document is not a full datasheet. For more
information regarding this product or to order samples
please contact your local National Semiconductor sales
office or visit http://www.national.com/support/dir.html
■ Linear charger with single input
■
■
■
■
■
■
■
■
■
■
■
USB or AC adapter input
28V OVP on the charger input
Four high-efficiency Synchronous Magnetic Buck
Regulators:
2 x 1A, 2 x 800 mA
2 regulators have DVS support
High-efficiency ECO mode @ low IOUT
Can be used with inductors as low as 1µH @ 4MHz clock
Buck1, Buck2 and Buck4 have ramp control to change rate
of change of output
11 General-type Low Noise LDOs
7 x 300 mA
2 x 450 mA
2 x 150 mA
5 wide-input low-output (WILO) LDOs
2 x 10 mA
1 x 50 mA
2 x 150 mA
All LDOs S/W configurable
Two over-voltage protected outputs for USB transceivers
Real time clock with two alarms
Back-up battery charger
Momentary Power Loss detection
Interrupt Request to reduce S/W polling
I2C-compatible Serial Interface
100-bump 0.4 mm pitch micro SMDxt package
Applications
■ Smartphones
■ GSM, GPRS, EDGE, CDMA & WCDMA Handsets
Notice: For more information regarding this product, to order
samples, or for further information, please contact your local
National Semiconductor sales office.
© 2011 National Semiconductor Corporation
301130
www.national.com
LP3974 PRODUCT BRIEF
LP3974
PRODUCT BRIEF
LP3974
Typical Application Diagram
30113001
www.national.com
2
LP3974
Device Pin Diagram
30113002
TOP VIEW
100–Bump (0.4 mm pitch) micro SMDxt Package
Package Marking Information
30113003
Ordering Information
Order Number
Production Identification
Supplied as
LP3974RME/NOPB
3974
250 Tape & Reel
LP3974RMX/NOPB
3974
1000 Tape & Reel
3
www.national.com
LP3974
WILO-Type LDOs
Wide Input Low Output LDOs are designed to enable a lowered output voltage range with voltages down to 0.8V.
Operational Description
The LP3974 is designed for the charging and voltage rail requirements within mobile handsets. The linear charger accepts DC voltages to provide the correct charging and charge
maintenance profile for LI-Ion batteries. The charger outputs
are programmable to meet the varying needs of these types
of batteries. Powered from the Battery input to the device, 4
switching regulators and 16 LDO type linear regulators provide for distributed power within the handset.
SINGLE INPUT LINEAR CHARGER
LP3974 has a built-in Li-Ion/Li-Poly battery management system. Its main features are:
• One input - AC adapter or USB
• Integrated PMOS power routing switch
• CC/CV linear charging
• Selectable battery regulation voltage
• Flexible charging cycle control
• Wide array of charging current options
• Safety timer with time doubling
Application Information
BUCK INFORMATION
The LP3974 has four integrated high-efficiency step-down
DC-DC switching buck converters that deliver a constant voltage from a single cell battery to portable devices. Using
voltage mode architecture with synchronous rectification,
Bucks 1 and 2 have the ability to deliver up to 1A, Bucks 3
and 4 up to 800 mA, depending on the input voltage and output voltage, ambient temperature, and the inductor chosen.
There are two modes of operation depending on the current
required – PWM (Pulse Width Modulation), ECO (ECOnomy)
mode. The device operates in PWM mode at load currents of
approximately 50 mA (typ.) or higher. Lighter output current
loads cause the device to automatically switch into ECO
mode for reduced current consumption and a longer battery
life. Buck1 has DVS capability using external SET1, SET2 inputs while Buck2 has DVS capability via SET3 input. Additional features include soft-start, under voltage protection,
current overload protection, and thermal shutdown protection.
Only three external power components per buck are required
for implementation.
Charger Function
A charge management system allowing safe charge and
maintenance of a Li-Ion battery is implemented on the
LP3974.
Following the correct detection of a voltage at the charger input, the charger enters pre-charge mode. In this mode the
battery is charged with a small constant current. Settings for
the battery current in pre-charge mode, full-rate voltage level,
and maximum pre-charge time are pre-set during factory test.
In full charging mode full rate constant current is applied to
the battery to raise the voltage to the termination level. The
charging current is programmable. When termination voltage
is reached, the charger is in constant voltage mode and a
constant voltage is maintained. After reaching the end-ofcharge condition, the charge management isolates the battery and enters the maintenance mode. A maintenance mode
enables the battery voltage to be maintained at the correct
level. If restart conditions have been met, then the charge cycle is re-initiated to re-establish the termination voltage level.
LDO INFORMATION
All LDOs can be programmed through serial interface for different output voltage values which are summarized in the
output voltage selection tables below.
At the PMU power on, LDOs start up according to the selected
startup sequence and the default voltages.
For stability all LDOs need to have external capacitors with
recommended value of 1µF connected to the output . It is important to select the type of capacitor whose capacitance will
in no case (voltage, temperature, etc) be outside of limits
specified in the LDO electrical characteristics.
BACKUP BATTERY CHARGER
Backup battery charger (BBC) is intended for charging an external coin battery. It consists of Voltage Limited Current
Source with 1kΩ output resistor. By default it is always on and
the output will be active when the supply voltage is above the
UVLO threshold typically 2.7V. The output voltage is programmable to 5 voltages from 2.9V to 3.3V. The default output
is set to 3.0V.
It is possible to turn backup battery charger off via registers.
BBC has a reverse current protection.
General-Type LDOs
The general LDOs are optimized to supply both analog and
digital loads having LOW NOISE (45 µVRMS for IOUT > 5mA)
and excellent PSRR (65 dB at 10 kHz) performance. They can
be programmed through the serial interface for different output voltage values.
In sleep mode quiescent current is lowered to 30 µA for energy saving; in this mode these LDOs should not be loaded
by more than 3-5mA of output current.
The innovative design of these general type LDOs reduces
the sensitivity to the placement of the output capacitor. These
general purpose LDOs do not need the output capacitor to be
placed close to the PMU as is the case for normal LDOs. If a
(1uF or more) capacitor is attached to a circuit load there is
no need to place an output capacitor at the PMU.
www.national.com
MOMENTARY POWER LOSS
When power is removed from the PMU and MPL function is
enabled (RTC register 0x1B) then the Momentary Power Loss
(MPL) timer starts as unexpected powerdown has occurred.
This timer is set to the maximum duration allowed for a momentary power loss (RTC register 0x1B). If power is restored
before the timer expires, the MPL block will inform the LP3974
control logic about the MPL event.
The MPL circuit is powered from VCOIN pin. MPL timer uses
32.786 kHz RTC crystal oscillator for time base. Host processor needs to enable the MPL function every time the device
is powered up.
ANALOG SWITCHES
Two double pole – double throw switches are integrated on
the device and are powered from the VBATT domain. Separate supplies are used for the logic control; LDO9 supplies the
power for SW1, and an external supply at VLSW2 supplies
the logic on SW2. This arrangement allows some control over
the logic thresholds for each switch. These switches are de4
RTC time and alarm registers are user-writable.
Alarms registers are used to set periodical or one-time events.
The result of an alarm event depends on the PMU state. If the
PMU is in standby, then the alarm causes the PMU to start
up. If the PMU is in working mode, then the alarm creates an
interrupt.
INTERRUPTS
The LP3974 has 4 main interrupt registers, IRQ1-4. It also has
4 main interrupt masking registers such that if asserted, the
particular interrupt that causes an event will be ignored.
These interrupts are generated from normal start up / shutdown events, charger events, timed events and warning conditions.
OVERVOLTAGE-PROTECTED LDO OUTPUTS (SAFE1/2)
SAFE1/2 provide a regulated output of 4.7V from the charger
DC input. In this way high voltage protection can be provided
for low rated USB devices within the system. As it is derived
from the CHGIN pin the operational voltage range for this applies, ie. 4.5V to 7.5V.
DEVICE STATUS
The LP3974 has 2 status registers and 2 status masking registers.
RTC Operational Description
This Real Time Clock (RTC) has following features:
• Accurate time counting with fine-grained correction for
inaccuracies caused by environment
• Calendar for years 2000-2099 with leap year
compensation and automatic day of week calculation
• Two highly customizable alarms
All RTC data is presented in Binary Coded Decimal format
MASTER RESET
The LP3974 has a master reset input which, when brought
low, will power down the device for a preset time, then allow
the device to power back up. The device will power up with
all supplies reset to their default values.
5
www.national.com
LP3974
signed for break before make switching, with high speed
switching for rail to rail signals.
These devices operate over the entire supply range with a flat
response for On-Resistance. The switches are bi-directional
and hence the pins NC, NO, and COM can be used as inputs
or outputs. An input voltage supply of 1.5V to VBATT may be
applied at VLSW2 pin to enable SW2 to operate at lower input
logic thresholds.
LP3974
Physical Dimensions inches (millimeters) unless otherwise noted
Micro SMDxt 100 Package
NS Package Number RMD100AAA
X1 = 4.015mm ± 0.030mm
X2 = 4.015mm ± 0.030mm
X3 = 0.650mm ± 0.075mm
www.national.com
6
LP3974
Notes
7
www.national.com
LP3974 PRODUCT BRIEF
Notes
For more National Semiconductor product information and proven design tools, visit the following Web sites at:
www.national.com
Products
Design Support
Amplifiers
www.national.com/amplifiers
WEBENCH® Tools
www.national.com/webench
Audio
www.national.com/audio
App Notes
www.national.com/appnotes
Clock and Timing
www.national.com/timing
Reference Designs
www.national.com/refdesigns
Data Converters
www.national.com/adc
Samples
www.national.com/samples
Interface
www.national.com/interface
Eval Boards
www.national.com/evalboards
LVDS
www.national.com/lvds
Packaging
www.national.com/packaging
Power Management
www.national.com/power
Green Compliance
www.national.com/quality/green
Switching Regulators
www.national.com/switchers
Distributors
www.national.com/contacts
LDOs
www.national.com/ldo
Quality and Reliability
www.national.com/quality
LED Lighting
www.national.com/led
Feedback/Support
www.national.com/feedback
Voltage References
www.national.com/vref
Design Made Easy
www.national.com/easy
www.national.com/powerwise
Applications & Markets
www.national.com/solutions
Mil/Aero
www.national.com/milaero
PowerWise® Solutions
Serial Digital Interface (SDI) www.national.com/sdi
Temperature Sensors
www.national.com/tempsensors SolarMagic™
www.national.com/solarmagic
PLL/VCO
www.national.com/wireless
www.national.com/training
PowerWise® Design
University
THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION
(“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY
OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO
SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS,
IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS
DOCUMENT.
TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT
NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL
PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR
APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND
APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE
NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS.
EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO
LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE
AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR
PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY
RIGHT.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and
whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected
to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform
can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness.
National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other
brand or product names may be trademarks or registered trademarks of their respective holders.
Copyright© 2011 National Semiconductor Corporation
For the most current product information visit us at www.national.com
National Semiconductor
Americas Technical
Support Center
Email: [email protected]
Tel: 1-800-272-9959
www.national.com
National Semiconductor Europe
Technical Support Center
Email: [email protected]
National Semiconductor Asia
Pacific Technical Support Center
Email: [email protected]
National Semiconductor Japan
Technical Support Center
Email: [email protected]
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are
sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard
warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where
mandated by government requirements, testing of all parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,
or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a
warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual
property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied
by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive
business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional
restrictions.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all
express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not
responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably
be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing
such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products
and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be
provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in
such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at
the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are
designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated
products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products
Applications
Audio
www.ti.com/audio
Communications and Telecom www.ti.com/communications
Amplifiers
amplifier.ti.com
Computers and Peripherals
www.ti.com/computers
Data Converters
dataconverter.ti.com
Consumer Electronics
www.ti.com/consumer-apps
DLP® Products
www.dlp.com
Energy and Lighting
www.ti.com/energy
DSP
dsp.ti.com
Industrial
www.ti.com/industrial
Clocks and Timers
www.ti.com/clocks
Medical
www.ti.com/medical
Interface
interface.ti.com
Security
www.ti.com/security
Logic
logic.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Power Mgmt
power.ti.com
Transportation and Automotive www.ti.com/automotive
Microcontrollers
microcontroller.ti.com
Video and Imaging
RFID
www.ti-rfid.com
OMAP Mobile Processors
www.ti.com/omap
Wireless Connectivity
www.ti.com/wirelessconnectivity
TI E2E Community Home Page
www.ti.com/video
e2e.ti.com
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2011, Texas Instruments Incorporated
Similar pages