®
RT9460
Switch-Mode Single Cell Li-Ion Charger with USB-OTG
General Description
The RT9460 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 and regulation, and high accuracy voltage
regulation and charge termination circuits. Besides, the
charging current is regulated through the integrated
sensing resistors. The RT9460 also features USB On-
The-Go (OTG) support.
The RT9460 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 are
programmable via the I
2
C interface. The RT9460 resumes
the charge cycle whenever the battery voltage falls below
an internal recharge 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 RT9460 is available in the small WL-CSP-25B
2.52x2.52 packages.
Features
High Accuracy Voltage/Current Regulation
Average Input Current Regulation (AICR) : 0.1/0.15/
0.5/ to 3A per 0.1A
Minimum Input Voltage Regulation
½
For 5V Adaptor : 4V/4.25V/4.5V/4.75V
½
For 9V Adaptor : 7V/7.5V/8V/8.5V
Charge Current Regulation Accuracy :
±
5%
Charge Voltage Regulation Accuracy :
±
1% (0 to
85°C)
°
Integrated Power MOSFETS for up to 3.125A Charge
Rate
Support USB Charging Detection
Battery Temperature Sensing
Synchronous 0.75/1.5MHz 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 I
2
C
Automatic Charging
RoHS Compliant and Halogen Free
Applications
Cellular Telephones
Personal Information Appliances
Tablet PC, Power Bank
Portable Instruments
Simplified Application Circuit
RT9460
To Adaptor/USB
C
IN
VIN
MID
LX
SYS
L
C
MID
C
SYS
External Path
(Option)
C
BAT
+
To System
DP
DM
SCL
SDA
PGND
PPCTRL
BAT
VPTS
TS
R
PULL
R
NTC
Battery
Pack
Copyright
©
2017 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9460-04 August 2017
www.richtek.com
1
RT9460
Ordering Information
RT9460
Package Type
WSC : WL-CSP-25B 2.52x2.52 (BSC)
Note :
Richtek products are :
½
Pin Configuration
(TOP VIEW)
A1
VIN
B1
LX
C1
D1
SYS
E1
BAT
A2
VIN
B2
LX
C2
D2
SYS
E2
A3
MID
B3
C3
D3
STAT
E3
A4
IRQ
B4
C4
D4
TS
E4
A5
CEB
B5
SCL
C5
D5
DP
E5
BOOT OTG
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
PGND PGND VDDP AGND SDA
½
BAT PPCTRL VPTS DM
Marking Information
0E : Product Code
WL-CSP-25B 2.52x2.52 (BSC)
0E YM
DNN
YMDNN : Date Code
Copyright
©
2017 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
2
DS9460-04 August 2017
RT9460
Functional Pin Description
Pin No.
A1, A2
A3
A4
A5
B1, B2
B3
B4
B5
C1, C2
C3
C4
C5
D1, D2
D3
D4
D5
E1, E2
E3
E4
E5
Pin Name
VIN
MID
IRQ
CEB
LX
BOOT
OTG
SCL
PGND
VDDP
AGND
SDA
SYS
STAT
TS
DP
BAT
PPCTRL
VPTS
DM
Power input.
Connection point between reverse blocking MOSFET and high-side
switching MOSFET.
IRQ output node.
Enable control input. Low active. With internal 102k pull low resistor.
Switch node. Connect to an external inductor.
Bootstrap supply for high-side MOSFET. Connect a capacitor between
BOOT and LX.
Setting input pin OTG boost mode. With internal 102k pull low resistor.
Clock input for I
2
C. Open-drain output. Connect a pull-up resistor.
Power ground for switching charger.
Internal power for power stage.
Analog ground.
Data input for I
2
C. Open drain output. Connect a pull-up Resistor.
System voltage regulator node.
Charge status indicator (open drain).
Battery temperature detection pin.
USB charger type detection pin.
Charging current output node. Battery charging voltage regulation
feedback pin with power path.
Power path control pin (connect to external P-MOSFET gate).
Supply voltage for battery temperature detection.
USB charger type detection pin.
Pin Description
Copyright
©
2017 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9460-04 August 2017
www.richtek.com
3
RT9460
Functional Block Diagram
TS VPTS
VIN
Protection
Battery
Temp.
Detection
Switching Charger
Controller
MID
BOOT
VDDP
Analog Base
LX
SCL
SDA
OTG
PGND
I C
State Machine
PP
Controller
SYS
BAT
AGND
2
IRQ DM DP CEB STAT
PPCTRL
Operation
The RT9460 is an integrated single cell Li-ion battery
switching charger with power path controller.
Base Circuits
Base circuits provide the internal power, VDDP and
reference voltage and bias current.
Protection Circuits
The protection circuits include the VINOVP, VINUVLO,
BATOVP and OTP circuits. The protection circuits turn
off the charging when the input power or die temperature
is in abnormal level.
Buck Regulator for charging and Boost Regulator
as OTG
The multi-loop controller controls the operation of charging
process and current supply to the system. It also controls
the circuits as a Boost converter for OTG applications.
Battery Detection
The RT9460 is capable of doing the battery absence
detection. The detection protects the charger when battery
is removed accidentally.
Adaptor Detection
If the poor input power source is connected to RT9460,
the operation is shut down by the adaptor detection.
Copyright
©
2017 Richtek Technology Corporation. All rights reserved.
Power Path Management and Control
Once the battery voltage increase to a defined system
minimum regulation voltage, the internal path between
SYS and BAT will be fully turned on (Cool PPM operation).
That is, a better charging efficiency can be derived. When
end of charge occurs, the charing stops and the internal
path will be off.
USB Charger Detection
The RT9460 detects and distinguishes SONY, APPLE
NIKON and USB Charger (Standard Charger Port,
Charging Downstream Port and Dedicated Charger Port)
via DP and DM pins.
TS Detection
The RT9460 detects the temperature of the battery pack
via TS and VPTS pins. The VPTS pin provides a constant
voltage source used to drive the voltage divider composed
of a pulled-high resister and a
NTC resister. The RT9460
reports the sensing results via IRQ and status bits for
COLD, COOL, WARM and HOT.
I
2
C Controller
The key parameters of charging and OTG are programmable
through I
2
C commands.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
4
DS9460-04 August 2017
RT9460
Absolute Maximum Ratings
(Note 1)
−0.3V
to 28V
−0.3V
to 28V
−0.3V
to 20V
−0.3V
to 6V
−0.3V
to 6V
3.11W
Supply Input Voltage, VIN -----------------------------------------------------------------------------------------------
MID, BOOT -----------------------------------------------------------------------------------------------------------------
LX -----------------------------------------------------------------------------------------------------------------------------
MID
−
VIN, BOOT
−
LX --------------------------------------------------------------------------------------------------
Other Pins ------------------------------------------------------------------------------------------------------------------
Power Dissipation, P
D
@ T
A
= 25°C
WL-CSP-25B 2.52x2.52 (BSC) ----------------------------------------------------------------------------------------
WQFN-32L 4x4 ------------------------------------------------------------------------------------------------------------ 3.59W
Package Thermal Resistance (Note 2)
WL-CSP-25B 2.52x2.52 (BSC),
θ
JA
---------------------------------------------------------------------------------- 32.1°C/W
WQFN-32L 4x4,
θ
JA
------------------------------------------------------------------------------------------------------
WQFN-32L 4x4,
θ
JC
------------------------------------------------------------------------------------------------------
Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------
Junction Temperature ----------------------------------------------------------------------------------------------------
27.8°C/W
7°C/W
260°C
150°C
Storage Temperature Range --------------------------------------------------------------------------------------------
−65°C
to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) --------------------------------------------------------------------------------------------- 2kV
MM (Machine Model) ----------------------------------------------------------------------------------------------------- 200V
(Note 4)
Recommended Operating Conditions
Supply Input Voltage, VIN ----------------------------------------------------------------------------------------------- 4.3V to 9V
Junction Temperature Range -------------------------------------------------------------------------------------------
−40°C
to 125°C
Ambient Temperature Range -------------------------------------------------------------------------------------------
−40°C
to 85°C
Electrical Characteristics
(V
IN
= 5V, V
BAT
= 4.2V, L = 2.2μH, C
IN
= 2.2μF, C
BATS
= 10μF, T
A
= 25°C, unless otherwise specified)
Parameter
Protection
V
IN
OVP Threshold Voltage
V
IN
OVP Hysteresis
Battery OVP
Battery OVP Hysteresis
Over-Temperature Protection
OTP Hysteresis
Thermal Regulation Threshold
System UVP Threshold
Voltage
Symbol
Test Conditions
Min
15
--
110
--
Typ
16
200
117
10
165
10
120
2.4
Max
17
--
124
--
--
--
--
--
Unit
V
mV
%
%
°C
°C
°C
V
OTP
Charge current begins to reduce
V
SYS_UVP
--
--
--
--
Copyright
©
2017 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9460-04 August 2017
www.richtek.com
5