LP78084 Datasheet, PDF (1/20 Pages) Lowpower Semiconductor inc – Total Power solution of Portable Applications 800mA Charge +800mA Buck DC/DC+300mA LDO

Preliminary Datasheet
LP78084
Total Power solution of Portable Applications
800mA Charge +800mA Buck DC/DC+300mA LDO
General Description
The LP78084 is a complete constant-current/
constant-voltage linear battery charger for a single-cell
4.2V lithium-ion battery with a 800mA step-down converter,
and a 300mA low dropout (LDO) linear regulator. The
input voltage range is 3.75V to 5.5V for the battery
charger and 2.6V to 5.5V for the step-down converter and
linear regulator, making it ideal for applications operating
with single-cell lithium-ion/polymer batteries.
The battery charger offers an integrated pass device, reverse
blocking protection, high accuracy current and voltage
regulation, charge status, and charge termination. The
charging current is programmable via external resistor
from 15mA to 800mA. In addition to these standard
features, the device offers current limit, thermal
protection, and soft-start.
The step-down converter is a highly integrated converter
operating at a 1.5MHz switching frequency, minimizing the
size of external components while keeping switching losses
low. It has independent input and enable pins. The output
voltage ranges from 0.6V to the input voltage.
The LP78084 linear regulator is designed for fast
transient response and good power supply ripple rejection.
Designed for 300mA of load current, it includes
short-circuit protection and thermal shutdown.
The LP78084 is available in a 16-lead 3mm*4mm TDFN
package and is rated over the -40°C to 85°C temperature
range.
Order Information
LP78084 - □ □ □ □ □
F: Pb-Free
Package Type
QV: TDFN-16
LDO Output Voltage
33: 3.3V
30: 3.0V
28: 2.8V
18: 1.8V
Applications
— Portable Media Players/MP3 players
— Cellular and Smart mobile phone
— PDA/DSC
— Bluetooth Applications
Features
— Battery Charger:
− Input Voltage Range : 3.75 V to 5.5V
− Constant-Current/Constant-Voltage Operation
with Thermal Feedback to Maximize Charge
Rate Without Risk of Overheating
− Internal 4.5 Hour Safety Timer for Termination
− Charge Current Programmable Up to 800mA
with 5% Accuracy
− C/10 Charge Current Detection Output
− 5 uA Supply Current in Shutdown Mode
— Synchronous Buck Converter:
− Input Voltage Range: 2.6V to 5.5V
− Output Voltage Range: 0.6V to VIN
− 800mA Output Current
− Up to 90% Efficiency
− 3 6 u A Quiescent Current
− 1.5MHz Switching Frequency
− 120 uS Start-Up Time
— Linear Regulator:
− 300mA Output Current
− Low Dropout: 150mV at 300mA
− Fast Line and Load Transient Response
− High Accuracy: ± 1.5%
− 8 4 u A Quiescent Current
— Short-Circuit, Over-Temperature, and Current
Limit Protection
— 3 m m × 4 m m TDFN-16 Package
— RoHS Compliant and 100% Lead (Pb)-Free
Typical Application Circuit
AC/USB
VA
ENB
ENA
LP78084
11 _AC/USB
BATT ⁸
6 _{EN_BAT}
9 _STAT
16 _VINB
LX ¹⁵
R1
FB ¹
3 _ENB
R2
4
VinA
5
OUTA
13 _ENA
Iset ⁷
VOUTB
VOUTA
BATT
Marking Information
Please see website.
LP78084 – 02 Ver. 1.1 Datasheet
Nov.-2007
Page 1 of 22