RT9458 Datasheet, PDF (1/27 Pages) Richtek Technology Corporation – Switch-Mode Single Cell Li-Ion Battery Charger

®
RT9458
Switch-Mode Single Cell Li-Ion Battery Charger
with USB-OTG
General Description
The RT9458 is a switch-mode single cell Li-Ion/Li-Polymer
battery charger for portable applications. It integrates a
synchronous PWM controller, power MOSFETs, input
current sensing, high accuracy voltage regulation and
charge termination circuits. The RT9458 also features USB
On-The-Go (OTG).
The RT9458 optimizes the charging task by using a control
algorithm to vary the charge rate via different modes,
including pre-charge mode, fast charge mode, and constant
voltage mode. The key charge parameters can be
programmed via the I²C interface. The RT9458 resumes
the charge cycle whenever the battery voltage falls below
an internal threshold and automatically enters sleep mode
when the input power supply is removed.
Other features include under-voltage protection, over-
voltage protection, thermal regulation and reverse leakage
protection.
The RT9458 is available in the small WL-CSP-20B
2.1x1.87 (BSC) package.
Marking Information
4EW
4E : Product Code
W : Date Code
Features
 Support Quick Start for Charger
 High Accuracy Voltage/Current Regulation
 Input Current Regulation : 100mA/500mA/700mA/
1A
 Minimum Input Voltage Regulation : 4.1V to 4.7V
Per 0.1V Step
 Charge Voltage Regulation Accuracy : ±1% (0 to
85°C)
 Charge Current Regulation Accuracy : ±5%
 Built-In Input Current Sensing and Limiting
 Integrated Power MOSFETS for up to 1.55A Charge
Rate
 Integrated Sensing Resistors for Charging Current
Sensing
 Synchronous 1.5MHz Fixed Frequency PWM
Controller with up to 95% Duty Cycle
 Reverse Leakage Protection to Prevent Battery
Drainage
 Thermal Regulation and Protection
 Over-Temperature Protection
 Input Over-Voltage Protection
 IRQ Output for Communication with I²C
 Automatic Charging
 RoHS Compliant and Halogen Free
Applications
 Cellular Telephones
 Personal Information Appliances
 MP3 Players
 Portable Instruments
Simplified Application Circuit
To Adaptor/USB
VIN
VMID
RT9458
LX
OTG
SCL
ISNSIN
SDA
IRQ
BATS
GND
+
Battery
Copyright ©2017 Richtek Technology Corporation. All rights reserved.
DS9458-02 February 2017
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
1