®
RT9527
Single Cell Li-Ion Battery Charger with Adjustable Charging
Current for Portable Applications
General Description
Features
The RT9527 is a low cost single-cell Li-ion charger for low
current charge applications.
The RT9527 can be powered up from an AC adapter or
USB (Universal Serial Bus) port inputs. The RT9527 enters
sleep mode when VIN power is removed. The RT9527
optimizes the charging task by using a control algorithm,
which includes pre-charge mode, fast-charge mode and
constant voltage mode. The charging task is kept in
constant voltage mode to hold the battery in a full charge
condition. The charge current is adjustable via an external
resistor. The internal thermal feedback circuitry regulates
the die temperature to optimize the charge rate for all
ambient temperatures. The RT9527 features 28V
maximum rating voltages for VIN. Other features include
under voltage protection and over voltage protection for
the AC adapter supply.
Applications
The RT9527 is available in a WDFN-8L 2x2 package.
Ordering Information
RT9527
Package Type
QW : WDFN-8L 2x2 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Cellular Phones
Digital Cameras
PDAs and Smart Phone
Portable Instruments
Marking Information
0S : Product Code
Note :
0SW
Richtek products are :
28V Maximum Rating for AC Adapter
Internal Integrated Power FETs
Adjustable Charging Current
Programmable Safe Charge Timer
NTC Thermistor Input
Battery Reverse Protection
ISET Pin Short Protection
Charge Status Indicator
AC Adapter Power Good Status Indicator
End of Charge Current is 10% of Fast-Charge Current
Under Voltage Protection
Over Voltage Protection
Thermal Feedback Optimized Charge Rate
Small Thermally Enhanced 8-Lead WDFN Package
RoHS Compliant and Halogen Free
W : Date Code
RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
Simplified Application Circuit
Input Power
VIN
RT9527
TIMER
BAT
PGOOD
CHG
ISET
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DS9527-03 January 2017
Battery
Indicator
GND
is a registered trademark of Richtek Technology Corporation.
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1
RT9527
Pin Configuration
VIN
PGOOD
CHG
GND
1
2
3
4
GND
(TOP VIEW)
9
8
7
6
5
BAT
TS
TIMER
ISET
WDFN-8L 2x2
Functional Pin Description
Pin No.
1
Pin Name
Pin Function
VIN
Supply voltage input. VIN can withstand up to 28V input.
2
PGOOD
Power good status output. Active-low, open-drain output.
3
CHG
Charger status output. Active-low, open-drain output.
4,
GND
9 (Exposed Pad)
Ground. The exposed pad must be soldered to a large PCB and connected to
GND for maximum power dissipation.
5
ISET
Charge current setting.
6
TIMER
Safe-charge timer setting.
7
TS
Temperature sense input. The TS pin connects to a battery’s thermistor to
determine whether the battery is too hot or too cold for charging operation. If the
battery’s temperature is out of range, charging is paused until it re-enters the
valid range.
8
BAT
Charge current output for battery.
Functional Block Diagram
BAT
Switch
Well
VIN
BASE
Too Cold
VREF
VIN
Thermal
Circuit
+
-
IBIAS
+
Too Hot
Sleep
Mode
ISET
Current
Set Block
CC/CV/TR
Multi Loop
Controller
TIMER
TS
-
TMIER
CHG
OVP
Logic
UVLO
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PGOOD
GND
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DS9527-03 January 2017
RT9527
Operation
The RT9527 is a Li-ion charger that can support the input
voltage range from 4.4V to 6V. It provides a wide fastcharge current setting ranging from 10mA up to 600mA.
CC/CV/TR Multi Loop Controller
Change Current Setting
Too Hot or Too Cold
The charging current is adjustable via an external resistor
between the ISET and GND pin.
The temperature sense input TS pin can be connected a
thermistor to determine whether the battery is too hot or
too cold for charging operation. If the battery's temperature
is out of range, charging is paused until it re-enters the
valid range.
UVLO
If the input voltage (VIN ) is lower than the threshold voltage
VUVLO − ΔVUVLO, the charger will stop charging until VIN
is larger than VUVLO.
OVP
If the input voltage (VIN) is higher than the threshold voltage
VOVP, the internal OVP signal will go high and the charger
will stop charging until VIN is below VOVP − ΔVOVP.
Switch Well
The switch well will choose the highest voltage between
VIN and BAT to prevent the power switch from damage.
There are constant current loop, constant voltage loop and
thermal regulation loop to control the charging current.
PGOOD
The PGOOD is an open-drain output used to indicate the
input voltage status. PGOOD will assert low when VIN is
in the proper working range.
CHG
The CHG pin is an open-drain output. CHG will assert low
when the charger starts to charge the battery and become
high impedance when the termination current is reached.
TIMER
Sleep Mode
When the voltage difference between VIN and BAT is under
VOS_L, the charger will enter sleep mode to save the system
power consumption.
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
DS9527-03 January 2017
The charger contains the safety timer. When the charging
time is longer than tPCHG in the pre-charge mode or tFCHG
in the fast-charge mode, time fault happens. Then, the
charger will be turned off and the CHG pin will become
high impedance.
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RT9527
Absolute Maximum Ratings
(Note 1)
Supply Input Voltage, VIN ---------------------------------------------------------------------------------------------CHG, PGOOD, TS -----------------------------------------------------------------------------------------------------Other Pins ----------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
WDFN-8L 2x2 ------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2)
WDFN-8L 2x2, θJA ------------------------------------------------------------------------------------------------------WDFN-8L 2x2, θJC ------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------------Junction Temperature --------------------------------------------------------------------------------------------------Storage Temperature Range ------------------------------------------------------------------------------------------ESD Susceptibility (Note 3)
HBM (Human Body Model) --------------------------------------------------------------------------------------------
Recommended Operating Conditions
−0.3V to 28V
−0.3V to 28V
−0.3V to 6V
2.19W
45.5°C/W
11.5°C/W
260°C
150°C
−65°C to 150°C
2kV
(Note 4)
Supply Input Voltage, VIN ---------------------------------------------------------------------------------------------- 4.4V to 6V
Junction Temperature Range ------------------------------------------------------------------------------------------ −40°C to 125°C
Ambient Temperature Range ------------------------------------------------------------------------------------------ −40°C to 85°C
Electrical Characteristics
(VIN = 5V, VBAT = 4V, TA = 25°C, unless otherwise specified)
Parameter
Supply Input
VIN Under Voltage Lockout
Threshold
VIN Under Voltage Lockout
Hysteresis
VIN BAT VOS Rising
Symbol
Test Conditions
Min
Typ
Max
Unit
VUVLO
VIN = 0V to 5V
3.1
3.3
3.5
V
VUVLO
VIN = 5V to 0V
--
240
--
mV
VOS_H
--
100
200
mV
VIN BAT VOS Falling
VOS_L
10
50
--
mV
VIN Standby Current
ISTANDBY
VBAT = 4.5V
--
1
2
mA
BAT Sleep Leakage Current
ISLEEP
VIN = 0V
--
--
1
A
Battery Voltage Regulation
VREG
0C to 85C
4.158
4.2
4.242
V
Re-Charge Threshold
VREGCHG Battery Regulation Recharge Level
60
100
140
mV
--
0.8
--
10
--
600
mA
600
690
Voltage Regulation
VIN Power FET On-Resistance RDS(ON)
IBAT = 450mA
Current Regulation
VIN Charge Setting Range
ICHG
KCHG_F1
ICHG_F1 = KCHG_F1 / RISET,
ICHG_F1 = 10mA to 50mA
510
KCHG_F2
ICHG_F2 = KCHG_F2 / RISET,
ICHG_F2 = 50mA to 600mA
570
Fast-Charge Current Factor
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4
A
600
630
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DS9527-03 January 2017
RT9527
Parameter
Pre-Charge Current Factor
Symbol
Test Conditions
Min
Typ
Max
Unit
KCHG_P
ICHG_P = KCHG_P / RISET
30
60
90
A
BAT Pre-Charge Threshold
VPRECH
V BAT Falling
2.7
2.8
2.9
V
BAT Pre-Charge Threshold
Hysteresis
VPRECH
--
200
--
mV
5
10
15
%
Pre-Charge
Charge Termination
Termination Current Ratio
ITERMI
V BAT > VPREC, ICHG < ITERMI ,
CHG = L to H
Protection
Thermal Regulation
TREG
--
125
--
C
Over Voltage Protection
VOVP
6.2
6.5
6.8
V
Over Voltage Protect Hysteresis
VOVP
--
0.2
--
V
ISET Pin Short Protection
RSHORT
375
500
625
60
61
62
%V IN
--
2
--
%V IN
29
30
31
%V IN
--
2
--
%V IN
1800
NTC
Cold Temperature Fault
Threshold Voltage
VCOLD
Cold Temperature Fault
VCOLD
Threshold Hysteresis
Hot Temperature Fault Threshold
VHOT
Voltage
Hot Temperature Fault Threshold
VHOT
Hysteresis
Rising Threshold
Falling Threshold
Timer
Pre-Charge Fault Time
tPCHG
CTIMER = 1F (1 / 8 x tFCH G)
1440
2160
s
Fast-Charge Fault Time
tFCHG
CTIMER = 1F
11520 14400 17280
s
PGOOD Pull Down Voltage
VPGOOD
IPGOOD = 5mA
--
200
--
mV
CHG Pull Down Voltage
VCHG
ICHG = 5mA
--
200
--
mV
PGOOD Deglitch Time
tPGOOD
Time measured from the edge
V IN = 0V to 5V in 1s to PGOOD = L
--
2
--
ms
--
50
--
s
tOVP_R
--
2
--
ms
tPF
--
25
--
ms
tFP
--
25
--
ms
Termination Deglitch Time
tTERMI
--
25
--
ms
Recharge Deglitch Time
tRECHG
--
100
--
ms
Sleep Deglitch Time
tNO-IN
--
25
--
ms
Pack Temperature Fault
Detection Deglitch Time
tTS
--
25
--
ms
Other
Input Over Voltage Blanking Time tOVP
Input Over Voltage Recovery
Time
Pre-Charge to Fast-Charge
Deglitch Time
Fast-charge to Pre-Charge
Deglitch Time
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DS9527-03 January 2017
is a registered trademark of Richtek Technology Corporation.
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RT9527
Note 1. Stresses beyond those listed “Absolute Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is
measured at the exposed pad of the package.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
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is a registered trademark of Richtek Technology Corporation.
DS9527-03 January 2017
RT9527
Typical Application Circuit
1
Adapter or USB
RT9527
8
VIN
BAT
CIN
R1
2
R2
3
RT1
RNTC
PGOOD
CHG
TS 7
6
TIMER
4,
GND
9 (Exposed Pad)
ISET 5
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COUT
RT2
RISET
CTIMER
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RT9527
Typical Operating Characteristics
TS Inserted/Removed
Charge On/Off Control from VIN
VCHG
(1V/Div)
VIN
(5V/Div)
VCHG
(5V/Div)
VBAT
(5V/Div)
VBAT
(2V/Div)
IBAT
(500mA/Div)
VTS
(2V/Div)
IBAT
(500mA/Div)
VIN = 5V, VBAT = Real Battery, RISET = 1kΩ
VIN = 5V, VBAT = Real Battery, RISET = 1kΩ
Time (500ms/Div)
Time (25ms/Div)
VIN Hot-Plug with NTC/Without Battery
VIN Hot-Plug Without NTC/Battery
VIN
(5V/Div)
VPGOOD
(5V/Div)
VIN
(5V/Div)
VPGOOD
(5V/Div)
VBAT
(5V/Div)
VBAT
(5V/Div)
VTS
(5V/Div)
VTS
(5V/Div)
VIN = 5V
Time (100ms/Div)
Time (100ms/Div)
VIN Hot-Plug with NTC/Battery
VIN Over Voltage Protection
VIN
(5V/Div)
VPGOOD
(5V/Div)
VBAT
(5V/Div)
VTS
(5V/Div)
IBAT
(500mA/Div)
VIN
(10V/Div)
V CHG
(10V/Div)
VIN = 5V, VBAT = Real Battery, RISET = 1kΩ
Time (100ms/Div)
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VIN = 5V
VBAT
(5V/Div)
IBAT
(500mA/Div)
VIN = 5V to 15V, VBAT = Real Battery, RISET = 1kΩ
Time (100ms/Div)
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DS9527-03 January 2017
RT9527
ICHG Thermal Regulation vs. Temperature
OVP Threshold Voltage vs. Temperature
6.65
I CHG Thermal Regulation (mA)1
700
OVP Voltage (V)
6.60
Rising
6.55
6.50
6.45
6.40
6.35
Falling
6.30
VIN = 5V, VBAT = 3.7V
6.25
600
500
400
300
200
100
VIN = 5V, VBAT = 3.7V, ICHG = 600mA
0
-50
-25
0
25
50
75
100
125
-50
-25
0
Temperature (°C)
ICHG Thermal Regulation vs. Temperature
75
100
125
Battery Regulation Voltage vs. Temperature
4.300
4.275
Battery Voltage (V)
I CHG Thermal Regulation (mA)1
50
Temperature (°C)
12
9
6
3
4.250
4.225
4.200
4.175
4.150
4.125
VIN = 5V, VBAT = 3.7V, ICHG = 10mA
VIN = 5V
0
4.100
-50
-25
0
25
50
75
100
125
0
Temperature (°C)
10
20
30
40
50
60
70
80
90
Temperature (°C)
Pre-Charge Current vs. Battery Voltage
Fast-Charge Current vs. Battery Voltage
70
800
60
750
Fast-Charge Current (mA)1
Pre-Charge Current (mA)
25
50
40
30
20
10
700
650
600
550
500
450
VIN = 5V, RISET = 1kΩ
VIN = 5V, RISET = 1kΩ
0
400
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
Battery Voltage (V)
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3
3
3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9
4
4.1
Battery Voltage (V)
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RT9527
Application Information
The RT9527 is a fully integrated low cost single-cell Liion battery charger ideal for portable applications. The
internal thermal feedback circuitry regulates the die
temperature to optimize the charge rate at all ambient
temperatures. The RT9527 features 20V maximum rating
voltages for VIN. Other features include under voltage
protection and over voltage protection for AC adapter
supply, as well as a charging time monitor.
Pre-Charge Mode
When the output voltage becomes lower than 2.8V, the
charging current reduces to 10% of the setting current to
protect the battery life time as shown below :
Charge State
Charging
Charging suspended
by thermal loop
Safety timers expired
TS fault
Charging done
Recharging after
termination
No valid input power
CHG Output
Low (for first charger cycle)
High impedance
Low (for first charger cycle)
High impedance
PGOOD Indicator
ICHG_P = KCHG_P / RISET
This open-drain output pin is used to indicate the input
voltage status. PGOOD output asserts low when
where KCHG_P is the pre-charge current factor.
1. VIN > VUVLO
Fast-Charge Mode
2. (VIN − VBAT) > VOS_H
When the output voltage becomes higher than 3V, the
charging current will be equal to the setting current which
is determined by RISET.
3. VIN < VOVP
ICHG_F = KCHG_Fx / RISET
It can be used to drive an LED or communicate to the
host processor. Note that “LOW” indicates the opendrain transistor is turned on and the LED is bright.
where KCHG_Fx is the fast-charge current factor.
Charge Termination
Constant Voltage Mode
When the charge current is lower than the charge
termination current ratio (10% = ICHG / ICHG_F) for VBAT >
4.1V and the time is larger than the deglitch time (25ms),
CHG transits from low to high. CHG will be latched high
unless the power is re-toggled.
As the output voltage is near 4.2V, the charging current
will be reduced to maintain the output voltage. The charger
remains active and maintains the output voltage at 4.2V
in order to keep the battery in a full charge state.
Recharge Mode
When the chip is in charge termination mode, the charging
current goes down to zero and the battery voltage drops
to 4.1V. After a deglitch time of 100ms (typ.), the battery
begins recharging. However, when recharge happens, the
indicator CHG remains in logic high.
CHG Indicator
The CHG pin is an open-drain output. CHG will assert low
when the charger starts to charge the battery and become
high impedance when the charge termination current is
reached. The CHG signal is interfaced either with a
microprocessor GPIO or an LED for indication.
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ISET Pin Short Protection
After VIN power plugs in, RT9527 will detect that ISET pin
is short to ground or not. If RISET is smaller than RSHORT,
RT9527 regard that ISET pin is short to ground. Then,
RT9527 will disable charge function until VIN power reset.
If RISET is larger than RSHORT, RT9527 will charge. If RT9527
begins charge status and ISET pin is short to ground,
thermal regulation will work to limit junction temperature
around 125°C.
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DS9527-03 January 2017
RT9527
Battery Connect Reverse
310R TCR TH
117R TC 427R TH
R T1 = 7R THR T2
3 R TH R T2
R T2 =
If battery is connected reversely, it causes that the voltage
of BAT pin is negative. RT9527 will disable charger function
until battery voltage is normal.
Time Fault
Temperature Regulation
In order to maximize charge rate, the RT9527 features a
junction temperature regulation loop. If the power
dissipation of the IC results in junction temperature greater
than the thermal regulation threshold (125°C), the RT9527
will cut back on the charge current and disconnect the
battery in order to maintain thermal regulation at around
125°C. This operation continues until the junction
temperature falls below the thermal regulation threshold
(125°C) by the hysteresis level. This feature prevents the
maximum power dissipation from exceeding typical design
conditions.
The Fast-Charge Fault Time is set according to the following
equations :
Fast-Charge Fault Time : tFCHG = 14400 x CTIMER (s)
Pre-Charge Fault Time : tPCHG = 1 / 8 x tFCHG (s)
where the CTIMER unit is in μF.
When time fault happens, the charger cycle will be turned
off and the CHG pin will become high impedance.
VBAT
IBAT
IBAT (IPREC)
IBAT (ICHG)
VBATREG
Pre-charge
stage
(Pre-charge
current)
Fast-charge stage
(Constant current)
Fast-charge stage
(Constant Voltage)
Sleep mode
The RT9527 enters sleep mode if both the AC and USB
ports are removed from the input. This feature prevents
draining the battery during the absence of an input supply.
VBAT
(VPREC)
Battery Pack Temperature Monitoring
The RT9527 features an external battery pack temperature
monitoring input. The TS input connects to the NTC
thermistor in the battery pack to monitor battery
temperature and prevent danger over temperature
conditions. If at any time the voltage at TS falls outside of
the operating range, charging will be suspended. The
timers maintain their values but suspend counting. When
charging is suspended due to a battery pack temperature
fault, the CHG pin remains low and continues to indicate
charging.
VIN
Too Cold
NTC_fault
+
Too Hot
-
Thermal Considerations
For continuous operation, do not exceed absolute
maximum junction temperature. The maximum power
dissipation depends on the thermal resistance of the IC
package, PCB layout, rate of surrounding airflow, and
difference between junction and ambient temperature. The
maximum power dissipation can be calculated by the
following formula :
PD(MAX) = (TJ(MAX) − TA) / θJA
RT2
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
TS
RNTC
Charging Profile
RT1
+
Charging State
For recommended operating condition specifications, the
maximum junction temperature is 125°C. The junction to
ambient thermal resistance, θJA, is layout dependent. For
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
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11
RT9527
WDFN-8L 2x2 package, the thermal resistance, θJA, is
45.5°C/W on a standard JEDEC 51-7 four-layer thermal
test board. The maximum power dissipation at TA = 25°C
can be calculated by the following formula :
PD(MAX) = (125°C − 25°C) / (45.5°C/W) = 2.19W for WDFN8L 2x2 package
Place CIN near the IC to
improve performance.
Maximum Power Dissipation (W)1
3.0
Four-Layer PCB
Connect the Exposed
Pad to a ground plane.
VIN
GND
CIN
R2 R1 VIN
PGOOD
CHG
GND
1
2
3
4
COUT
GND
The maximum power dissipation depends on the operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curve in Figure 1 allows the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
The connection of RISET should be isolated from other
noisy traces. A short wire is recommended to prevent
EMI and noise coupling.
9
8
7
6
5
BAT
TS
TIMER
ISET
RISET
GND
GND should be connected to a
strong ground plane for heat
sinking and noise protection.
RT1
RT2
CTIMER
The RISET connection copper area
should be minimized and kept far
away from noise sources.
2.5
Figure 2. PCB Layout Guide
2.0
1.5
1.0
0.5
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 1. Derating Curve of Maximum Power Dissipation
Layout Considerations
The RT9527 is a fully integrated low cost single cell Li-Ion
battery charger ideal for portable applications. Careful PCB
layout is necessary. For best performance, place all
peripheral components as close to the IC as possible. A
short connection is highly recommended. The following
guidelines must be strictly followed when designing a PCB
layout for the RT9527.
Input and output capacitor should be placed close to IC
and connected to ground plane. The trace of input in the
PCB should be placed far away from the sensitive devices
and shielded by the ground.
The GND and exposed pad should be connected to a
strong ground plane for heat sinking and noise protection.
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is a registered trademark of Richtek Technology Corporation.
DS9527-03 January 2017
RT9527
Operation State Diagram for Charger Function (RT9527)
NO
Standby State
PFET = OFF
YES
YES
VBAT > 3V
Charge
Termination
VBAT = 4.2V
ICHG = 0A
CHG = H (latch)
NO
Fast-Charge
Mode
CHG = L
VOVP > VIN > VUVLO
Reset
Time Counter
NO
VBAT < VREG
- 0.1V
NO
YES
YES
Time >Ttermi
Pre-CHG State
ICHG_P = 0.1 x
YES
Power Off State
PFET = OFF
YES
ICHG_F
CHG = L
VIN – VBAT > VOS
Time < Tfchg
NO
Time < Tfchg
VBAT ~4.2V
NO
NO
NO
Any State
VIN > VOVP
YES
IBAT < Iterm
YES
Sleep State
PFET = OFF
Or VIN < VUVLO
NO
YES
YES
Power re-plug
CV Mode
CHG = L
FAULT
CHG = High impedance
PFET = OFF
NO
NO
VBAT < VREG - 0.1V
YES
YES
Charge
Termination
VBAT = 4.2V
ICHG = 0A
CHG = H (latch)
NO
Fast-Charge
Mode
CHG = H (latch)
Reset
Time
Counter
NO
YES
NO
VBAT > 3V
Time > Ttermi
YES
VBAT ~4.2V
YES
IBAT < Iterm
Time < Tpchg
NO
NO
Time < Tpchg
YES
ICHG_F
CHG = L
NO
YES
CV Mode
CHG = H (latch)
YES
Pre-CHG State
ICHG_P = 0.1 x
VIN – VBAT > VOS
NO
FAULT
CHG = High impedance
PFET = OFF
Power re-plug
YES
Sleep State
PFET = OFF
NO
Note1 :
If termination happens, CHG will be latched H.
(VIN > VOVP or VIN < VUVLO or VIN – VBAT < VOS_L) will release CHG latch H state.
But VBAT < VREG - 0.1 can not release CHG latch H state.
Note2 :
If time out happens, CHG will become high impedance.
(VIN > VOVP or VIN < VUVLO or VIN – VBAT < VOS_L) will release time out state
Figure 3. Operation State Diagram for Charging
Copyright © 2017 Richtek Technology Corporation. All rights reserved.
DS9527-03 January 2017
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT9527
Outline Dimension
D2
D
L
E
E2
1
e
SEE DETAIL A
b
2
1
2
1
A
A1
A3
DETAIL A
Pin #1 ID and Tie Bar Mark Options
Note : The configuration of the Pin #1 identifier is optional,
but must be located within the zone indicated.
Dimensions In Millimeters
Dimensions In Inches
Symbol
Min
Max
Min
Max
A
0.700
0.800
0.028
0.031
A1
0.000
0.050
0.000
0.002
A3
0.175
0.250
0.007
0.010
b
0.200
0.300
0.008
0.012
D
1.950
2.050
0.077
0.081
D2
1.000
1.250
0.039
0.049
E
1.950
2.050
0.077
0.081
E2
0.400
0.650
0.016
0.026
e
L
0.500
0.300
0.020
0.400
0.012
0.016
W-Type 8L DFN 2x2 Package
Richtek Technology Corporation
14F, No. 8, Tai Yuen 1st Street, Chupei City
Hsinchu, Taiwan, R.O.C.
Tel: (8863)5526789
Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should
obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot
assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be
accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries.
www.richtek.com
14
DS9527-03 January 2017