DS9527L 01

®
RT9527L
Single Cell Li-Ion Battery Charger with Adjustable Charging
Current for Portable Applications
General Description
Features
The RT9527L is a low cost single-cell Li-ion charger for
low current charge applications.



The RT9527L can be powered up by an AC adapter or
USB (Universal Serial Bus) port inputs. The RT9527L enters
sleep mode when VIN power is removed. The RT9527L
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 RT9527L features 28V
maximum rating voltages for VIN. Other features include
under-voltage protection and over-voltage protection for the
AC adapter supply.











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
RoHS Compliant and Halogen Free
Applications

The RT9527L is available in the small thermally enhanced
WDFN-8L 2x2 package.



Ordering Information
RT9527L
Cellular Phones
Digital Cameras
PDAs and Smart Phone
Portable Instruments
Marking Information
Package Type
QW : WDFN-8L 2x2 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
2B : Product Code
2BW
W : Date Code
Note :
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
RT9527L
TIMER
BAT
PGOOD
CHG
ISET
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
Battery
Indicator
GND
is a registered trademark of Richtek Technology Corporation.
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1
RT9527L
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.
1
Pin Name
Pin Function
VIN
Supply Voltage Input. VIN can withstand up to 28V input.
2
PGOOD
Power Good Indicator 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 © 2014 Richtek Technology Corporation. All rights reserved.
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2
PGOOD
GND
is a registered trademark of Richtek Technology Corporation.
DS9527L-01 May 2014
RT9527L
Operation
The RT9527L 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 higher 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 pin 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 © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
The charger contains a 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.
is a registered trademark of Richtek Technology Corporation.
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RT9527L
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
Supply Input
VIN Under-Voltage Lockout
Threshold
VIN Under-Voltage Lockout
Hysteresis
VIN  BAT VOS Rising
Symbol
Test Conditions
Min
Typ
Max
Unit
V UVLO
V IN = 0V to 5V
3.1
3.3
3.5
V
VUVLO
V IN = 5V to 0V
--
240
--
mV
V OS_H
--
100
200
mV
VIN  BAT VOS Falling
V OS_L
10
50
--
mV
VIN Standby Current
I STANDBY
V BAT = 4.5V
--
1
2
mA
BAT Sleep Leakage Current
I SLEEP
V IN = 0V
--
--
1
A
Battery Voltage Regulation
V REG
0C to 85C
4.118
4.16
4.202
V
Re-Charge Threshold
VREGCHG Battery Regulation  Recharge Level
60
100
140
mV
--
0.8
--

mA
Voltage Regulation
VIN Power FET On-Resistance R DS(ON)
I BAT = 450mA
Current Regulation
VIN Charge Setting Range
I CHG
10
--
600
K CHG_F1
I CHG_F1 = K CHG_F1 / RISET,
I CHG_F1 = 10mA to 50mA
510
600
690
K CHG_F2
I CHG_F2 = K CHG_F2 / RISET,
I CHG_F2 = 50mA to 600mA
570
Fast-Charge Current Factor
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A
600
630
is a registered trademark of Richtek Technology Corporation.
DS9527L-01 May 2014
RT9527L
Parameter
Pre-Charge Current Factor
Symbol
Test Conditions
Min
Typ
Max
Unit
K CHG_P
ICHG_P = K CHG_P / RISET
30
60
90
A
V PRECH
VBAT Falling
2.7
2.8
2.9
V
--
200
--
mV
5
10
15
%
Pre-Charge
BAT Pre-Charge Threshold
BAT Pre-Charge Threshold
Hysteresis
VPRECH
Charge Termination
Termination Current Ratio
ITERMI
VBAT > VPREC, ICHG < ITERMI,
CHG = L to H
Protection
Thermal Regulation
T REG
--
125
--
C
Over-Voltage Protection
Over-Voltage Protection
Hysteresis
ISET Pin Short Protection
V OVP
6.2
6.5
6.8
V
VOVP
--
0.2
--
V
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
V COLD
Rising Threshold
VCOLD
Hot Temperature Fault Threshold
V HOT
Voltage
Hot Temperature Fault Threshold
VHOT
Hysteresis
Falling Threshold
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
V PGOOD
IPGOOD = 5mA
--
200
--
mV
CHG Pull-Down Voltage
V CHG
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 © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
is a registered trademark of Richtek Technology Corporation.
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5
RT9527L
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.
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
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is a registered trademark of Richtek Technology Corporation.
DS9527L-01 May 2014
RT9527L
Typical Application Circuit
1
Adapter or USB
RT9527L
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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DS9527L-01 May 2014
COUT
RT2
RISET
CTIMER
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RT9527L
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 (25ms/Div)
Time (500ms/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)
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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.
DS9527L-01 May 2014
RT9527L
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
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
4.25
Battery Regulation Voltage (V)1
I CHG Thermal Regulation (mA)1
50
Temperature (°C)
12
9
6
3
4.23
4.20
4.18
4.15
4.13
4.10
4.08
VIN = 5V, VBAT = 3.7V, ICHG = 10mA
VIN = 5V
0
4.05
-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)
Copyright © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
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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RT9527L
Application Information
The RT9527L 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 RT9527L 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 >
4.06V 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 4.16V, the charging current
will be reduced to maintain the output voltage. The charger
remains active and maintains the output voltage at 4.16V
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 4.06V. 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, the RT9527L will detect whether
the ISET pin is shorted to ground or not. If RISET is smaller
than RSHORT, the RT9527L considers that the ISET pin is
short to ground. Then, the RT9527L will disable charge
function until VIN power reset.
If RISET is larger than RSHORT, the RT9527L will charge. If
the RT9527L begins charge status and the ISET pin is
short to ground, thermal regulation will work to limit junction
temperature around 125°C.
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DS9527L-01 May 2014
RT9527L
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. The RT9527L will disable charger
function until battery voltage is normal.
Time Fault
Temperature Regulation
In order to maximize charge rate, the RT9527L 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 RT9527L
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 RT9527L 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 RT9527L 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 © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
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.
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RT9527L
Maximum Power Dissipation (W)1
2.8
Layout Considerations
Four-Layer PCB
0.8
The RT9527L is a fully integrated low cost single cell LiIon 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 RT9527L.
0.4

Input and output capacitors 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.
2.4
2.0
1.6
1.2
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.
DS9527L-01 May 2014
RT9527L
Operation State Diagram for Charger Function (RT9527L)
NO
Standby State
PFET = OFF
YES
YES
VBAT > 3V
Charge
Termination
VBAT = 4.16V
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 ~4.16V
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 = 4.16V
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 ~4.16V
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 © 2014 Richtek Technology Corporation. All rights reserved.
DS9527L-01 May 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT9527L
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
DS9527L-01 May 2014