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RT9527H
Single Cell Li-Ion Battery Charger with Adjustable Charging
Current for Portable Applications
General Description
Features
The RT9527H is a low cost single-cell Li-ion charger for
low current charge applications.



The RT9527H can be powered up from an AC adapter or
USB (Universal Serial Bus) port inputs. The RT9527H
enters sleep mode when VIN power is removed. The
RT9527H 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 RT9527H features 28V
maximum rating voltage for VIN. Other features include
under-voltage protection and over-voltage protection for the
AC adapter supply.









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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
Applications
The RT9527H is available in the WDFN-8L 2x2 package.


Ordering Information

RT9527H

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
1X : Product Code
Note :
1XW
W : Date Code
Richtek products are :

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
RT9527H
TIMER
BAT
PGOOD
CHG
ISET
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
Battery
Indicator
GND
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
1
RT9527H
Pin Configurations
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.
Pin Name
Pin Function
1
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.
Function 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
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
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2
PGOOD
GND
is a registered trademark of Richtek Technology Corporation.
DS9527H-00 March 2015
RT9527H
Operation
The RT9527H 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 pins.
The temperature sense input TS pin can be connected to
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 reenters 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.
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. The PGOOD will assert low when
VIN is in the proper working range.
CHG
The switch well will choose the highest voltage between
VIN and BAT to prevent the power switch from damage.
The CHG pin is an open-drain output. The CHG will assert
low when the charger starts to charge the battery and
becomes high impedance when the termination current is
reached.
Sleep Mode
TIMER
When the voltage difference between VIN and BAT is under
VOS_L, the charger will enter sleep mode to save the system
power consumption.
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.
Switch Well
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
is a registered trademark of Richtek Technology Corporation.
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3
RT9527H
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) ---------------------------------------------------------------------------------------------MM (Machine 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
200V
(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
Symbol
Test Conditions
Min
Typ
Max
Unit
Supply Input
VIN Under-Voltage Lockout
Threshold
VUVLO
VIN = 0V to 5V
3.1
3.3
3.5
V
VIN Under-Voltage Lockout
Hysteresis
VUVLO
VIN = 5V to 0V
--
240
--
mV
VIN  BAT VOS Rising
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
0C to 85C
4.306
4.35
4.394
V
Re-Charge Threshold
VREGCHG Battery Regulation  Recharge Level
60
100
140
mV
--
0.8
--

10
--
600
mA
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
600
690
KCHG_F2
ICHG_F2 = KCHG_F2 / RISET,
ICHG_F2 = 50mA to 600mA
570
600
630
Fast-Charge Current Factor
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
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A
is a registered trademark of Richtek Technology Corporation.
DS9527H-00 March 2015
RT9527H
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
VBAT 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
VBAT > 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
%VIN
--
2
--
%VIN
29
30
31
%VIN
--
2
--
%VIN
1800
NTC
Cold Temperature Fault
Threshold Voltage
Cold Temperature Fault
Threshold Hysteresis
Hot Temperature Fault Threshold
Voltage
Hot Temperature Fault Threshold
Hysteresis
VCOLD
Rising Threshold
VCOLD
VHOT
Falling Threshold
VHOT
Timer
Pre-Charge Fault Time
tPCHG
CTIMER = 1F (1 / 8 x tFCHG)
1440
2160
s
Fast-Charge Fault Time
tFCHG
CTIMER = 1F
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
VIN = 0V to 5V in 1s 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
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
is a registered trademark of Richtek Technology Corporation.
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5
RT9527H
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.
DS9527H-00 March 2015
RT9527H
Typical Application Circuit
1
Adapter or USB
RT9527H
8
VIN
BAT
CIN
R1
2
R2
3
RT1
RNTC
PGOOD
CHG
TS 7
6
TIMER
4,
GND
9 (Exposed Pad)
ISET 5
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
COUT
RT2
RISET
CTIMER
is a registered trademark of Richtek Technology Corporation.
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7
RT9527H
Typical Operating Characteristics
TS Inserted/Removed
Charge On/Off Control from VIN
V CHG
(1V/Div)
VIN
(5V/Div)
V CHG
(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
VIN = 5V
Time (100ms/Div)
Time (100ms/Div)
VIN Hot-Plug with NTC/Battery
VIN Over Voltage Protection
VIN
(5V/Div)
VPGOOD
(5V/Div)
VIN
(10V/Div)
V CHG
(10V/Div)
VBAT
(5V/Div)
IBAT
(500mA/Div)
VIN = 5V, VBAT = Real Battery, RISET = 1kΩ
Time (100ms/Div)
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
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VBAT
(5V/Div)
IBAT
(500mA/Div)
VIN = 5V to 15V, VBAT = Real Battery, RISET = 1kΩ
Time (100ms/Div)
is a registered trademark of Richtek Technology Corporation.
DS9527H-00 March 2015
RT9527H
OVP Threshold Voltage vs. Temperature
ICHG Thermal Regulation 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
600
500
400
300
200
100
VIN = 5V, VBAT = 3.7V, ICHG = 600mA
6.25
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
4.400
Battery Regulation Voltage (V)1
I CHG Thermal Regulation (mA)1
50
Temperature (°C)
12
9
6
3
4.375
4.350
4.325
4.300
4.275
4.250
4.225
VIN = 5V, VBAT = 3.7V, ICHG = 10mA
VIN = 5V
0
4.200
-50
-25
0
25
50
75
100
0
125
10
20
30
40
50
60
70
80
90
100
Temperature (°C)
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)
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
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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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RT9527H
Application Information
The RT9527H 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 RT9527H features 20V maximum rating
voltage 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 :
ICHG_P = KCHG_P / RISET
where KCHG_P is the pre-charge current factor.
Charge State
CHG Output
Charging
Charging suspended
by thermal loop
Low (for first charger cycle)
Safety timers expired
High impedance
TS fault
Low (for first charger cycle)
Charging done
Recharging after
termination
High impedance
No valid input power
PGOOD Indicator
This open-drain output pin is used to indicate the input
voltage status. PGOOD output asserts low when
1. VIN > VUVLO
Fast-Charge Mode
When the output voltage becomes higher than 3V, the
charging current will be equal to the setting current which
is determined by RISET.
ICHG_F = KCHG_Fx / RISET
2. (VIN − VBAT) > VOS_H
3. VIN < VOVP
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
As the output voltage is near 4.35V, the charging current
will be reduced to maintain the output voltage. The charger
remains active and maintains the output voltage at 4.35V
in order to keep the battery in a full charge state.
When the charge current is lower than the charge
termination current ratio (10% = ICHG / ICHG_F) for VBAT >
4.25V 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.
Recharge Mode
ISET Pin Short Protection
When the chip is in charge termination mode, the charging
current goes down to zero and the battery voltage drops
to 4.25V. After a deglitch time of 100ms (typ.), the battery
begins recharging. However, when recharge happens, the
indicator CHG remains in logic high.
After VIN power plugs in, the RT9527H will detect whether
the ISET pin is short to ground or not. If RISET is smaller
than RSHORT, the RT9527H regards that the ISET pin is
short to ground. Then, the RT9527H will disable charge
function until VIN power reset.
CHG Indicator
If RISET is larger than RSHORT, the RT9527H will charge. If
the RT9527H begins charge status and the ISET pin is
short to ground, thermal regulation will work to limit junction
temperature around 125°C.
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.
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
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is a registered trademark of Richtek Technology Corporation.
DS9527H-00 March 2015
RT9527H
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 the BAT pin is negative. The RT9527H will disable
charger function until battery voltage is normal.
Time Fault
Temperature Regulation
In order to maximize charge rate, the RT9527H 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
RT9527H 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.
Sleep mode
The RT9527H 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.
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.
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 :
Battery Pack Temperature Monitoring
PD(MAX) = (TJ(MAX) − TA) / θJA
The RT9527H 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.
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
VIN
Too Cold
NTC_fault
PD(MAX) = (125°C − 25°C) / (45.5°C/W) = 2.19W for
WDFN-8L 2x2 package
RT1
+
+
Too Hot
-
TS
RNTC
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
For recommended operating condition specifications, the
maximum junction temperature is 125°C. The junction to
ambient thermal resistance, θJA, is layout dependent. For
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 :
RT2
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.
is a registered trademark of Richtek Technology Corporation.
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11
RT9527H
Maximum Power Dissipation (W)1
2.5
Layout Considerations
Four-Layer PCB
The RT9527H is a fully integrated low cost single cell LiIon battery charger which is 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 RT9527H.
2.0
1.5
1.0
0.5

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.

The connection of RISET should be isolated from other
noisy traces. A short wire is recommended to prevent
EMI and noise coupling.
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 1. Derating Curve of Maximum Power Dissipation
Place CIN near the IC to
improve performance.
Connect the Exposed
Pad to a ground plane.
VIN
GND
R2 R1 VIN
PGOOD
CHG
GND
1
2
3
4
COUT
GND
CIN
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.
Figure 2. PCB Layout Guide
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is a registered trademark of Richtek Technology Corporation.
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RT9527H
Operation State Diagram for Charger Function (RT9527H)
NO
Standby State
PFET = OFF
YES
YES
VBAT > 3V
Charge
Termination
VBAT = 4.35V
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
YES
Time >Ttermi
Pre-CHG State
ICHG_P = 0.1 x
Power Off State
PFET = OFF
YES
ICHG_F
CHG = L
VIN – VBAT > VOS
Time < Tfchg
NO
Time < Tfchg
NO
YES
IBAT < Iterm
YES
Sleep State
PFET = OFF
Or VIN < VUVLO
VBAT ~4.35V
NO
NO
Any State
VIN > VOVP
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 = 4.35V
ICHG = 0A
CHG = H (latch)
NO
Fast-Charge
Mode
CHG = H (latch)
Reset
Time
Counter
NO
YES
NO
Time > Ttermi
YES
YES
IBAT < Iterm
VBAT > 3V
VBAT ~4.35V
Time < Tpchg
NO
NO
Time < Tpchg
YES
NO
YES
CV Mode
CHG = H (latch)
YES
Pre-CHG State
ICHG_P = 0.1 x
ICHG_F
CHG = L
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 © 2015 Richtek Technology Corporation. All rights reserved.
DS9527H-00 March 2015
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT9527H
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.
Symbol
Dimensions In Millimeters
Dimensions In Inches
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
DS9527H-00 March 2015