LP3910 Datasheet, PDF (1/6 Pages) Texas Instruments – Power Management IC for Hard-Drive-Based Portable Media Players

ADVANCE INFORMATION
November 2006
LP3910
Power Management IC for Hard Drive Based Portable Media
Players
General Description
The LP3910 is a programmable system power management
unit that is optimized for HDD-based Portable Media Players.
The LP3910 incorporates 2 low-dropout LDO voltage regula-
tors, 2 integrated Buck DC/DC converters with Dynamic Volt-
age Scaling (DVS), 1 wide load range Buck-Boost DC/DC
converter with programmable output voltage, a 4-channel 8-
bit A/D converter and a dual source Li-Ion/polymer battery
charger. The charger has the capability to charge and main-
tain a single cell battery from a regulated wall adapter or USB
power. When both USB and adapter sources are present,
then the adapter source takes precedence and switching be-
tween USB and adapter power sources is seamless. In addi-
tion, the battery charger supports power routing, which allows
system usage immediately after an external power source
has been detected. The LP3910 also incorporates some ad-
vanced battery management functions such as battery tem-
perature measurement, reverse current blocking for USB,
LED charger status indication, thermally regulated internal
power FETs, battery voltage monitoring, over-current protec-
tion and a 10 hour safety timer.
The Buck-Boost DC/DC converter targets the power man-
agement of Hard Disk Drives and maintains a typical operat-
ing voltage of 3.3V ±5% with a battery voltage below or above
this output level. The Buck-Boost output voltage can be se-
lected to be as low as 1.8V.
The 4-channel A/D converter measures the battery voltage
and charge current, which can be used for fuel gauging. Two
undedicated channels can be used to measure other analog
parameters such as discharge current, battery temperature,
keyboard resistor scanning and more.
The various IC parameters are programmable through a
400 kHz I²C compatible interface.
The LP3910 is available in a thermally-enhanced
6x6x0.8 mm 48 LLP package and operates over an ambient
temperature range of –40°C to +85°C.
Features
■ ^{2 low-dropout regulators -- LDO1 is used for general}
purpose applications, LDO2 is used for low-noise analog
applications. Both LDOs have programmable output
voltages.
■ ^{Green and Red LED charger status drivers}
■ ^{4-channel 8-bit dual slope a/d converter}
■ ^{2 High-efficiency DVS Buck converters}
■ ^{Wide load range Buck-Boost DC/DC converter}
■ ^{400 kHz I2C compatible interface}
■ ^{Linear constant-current / constant-voltage charger for}
single cell lithium-ion batteries
■ ^{USB and Adapter charging}
■ ^{System power supply management}
■ ^{6x6x0.8mm 48 LLP package}
■ ^{Voltage and thermal supervisory circuits}
■ ^{Continuous battery voltage monitoring}
■ ^{Interrupt Request output with 8 sources}
Key Specifications
■ ^{LDO1: 150 mA, 1.2V–3.3V}
■ ^{LDO2: 150 mA, 1.3V–3.3V}
■ ^{Buck1: 600 mA, 0.8V–2.0V}
■ ^{Buck2: 600 mA, 1.8V–3.3V}
■ ^{Buck-Boost: 1000 mA, 1.8V–3.3V}
■ ^{50 mΩ battery path resistance}
■ ^{100 mA–1000 mA full-rate charge current using wall}
adapter
■ ^{Selectable 0.05C and 0.1C EOC current}
■ ^{USB current limit of 100 mA, 500 mA, and 800 mA}
■ ^{USB pre-qual current of 50 mA}
■ ^{Selectable 4.1V, 4.2V or 4.38V battery termination}
voltages
■ ^{0.35% battery termination accuracy}
■ ^{±1 LSB INL/DNL on 8-bit a/d converter}
Applications
■ ^{Hard drive-based MP3 players}
■ ^{Portable media players}
■ ^{Portable gaming devices}
© 2006 National Semiconductor Corporation 202123
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