RICHTEK RT9519B

RT9519B
Linear Single Cell Li-lon Battery Charger with Auto Power
Path Management
General Description
Features
The RT9519B is an integrated single cell Li-ion battery
charger with Auto Power Path Management (APPM). No
external MOSFETs are required. The RT9519B enters
sleep mode when power is removed. Charging tasks are
optimized by using a control algorithm to vary the charge
rate, including pre-charge mode, fast charge mode and
constant voltage mode. For the RT9519B, the charge
current can also be programmed with an external resistor
and modified with an external GPIO. The scope that the
battery regulation voltage can be modified with an external
GPIO depends on the battery temperature. The internal
thermal feedback circuitry regulates the die temperature
to optimize the charge rate for all ambient temperatures.
The charging task will always be terminated in constant
voltage mode when the charging current reduces to the
termination current of 10% x ICHG_FAST. Other features
z
include under voltage protection and over voltage protection
for VIN the supply.
z
Ordering Information
Pin Configurations
28V Maximum Rating for VIN Power
z Selectable Power Current Limit (0.1A / 0.5A / 1.5A)
z Integrated Power MOSFETs
z Auto Power Path Management (APPM)
z Battery Charging Current Control
z Battery Regulation Voltage Control
z Programmable Charging Current and Safe Charge
Timer
z Under Voltage Protection, Over Voltage Protection
z Power Good and Charge Status Indicator
z Optimized Charge Rate via Thermal Feedback
z Thin 20-Lead WQFN Package
z RoHS Compliant and Halogen Free
Applications
z
z
Digital Cameras
PDAs and Smart Phones
Portable Instruments
RT9519B
(TOP VIEW)
USUS
SYS
SYS
SYS
TS_FAULT
Package Type
QW : WQFN-20L 3x3 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
20 19 18 17 16
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.
VIN
PGOOD
CHG
GND
ISETA
1
15
2
14
GND
3
4
21
5
13
12
11
6
7
8
VSET
ISETL
ISETU
VP
ISET
9 10
TS
TIMER
BAT
BAT
EN
Note :
Marking Information
46= : Product Code
46=YM
DNN
WQFN-20L 3x3
YMDNN : Date Code
DS9519B-01 April 2011
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1
RT9519B
Typical Application Circuit
Adapter
1 VIN
CIN
2.2µF
CSYS
R4
R3
SYS
R2
2 PGOOD
3
CHG
16 TS_FAULT
Power Good Indicator
Charge Indicator
TS_FAULT Indicator
TS
TIMER
Suspend
Normal
Suspend Mode
4.2V
20 USUS
15
7
CTIMER
1µF
1.5A
CBAT +
1µF
500mA
100mA
VIN Current Limit
1-Cell
Li+
RISETA
ISETA 5
ICHG
ISET 11
14
NTC
BAT 8, 9
VSET
4.05V
R1
6
10 EN
Chip Enable
See ISETU
VIN Current Limit
External Power Source
2.95V to 3.6V
VP 12
CVP
17, 18, 19
To System Load
RT9519B
ICHG/2
ISETL
13 ISETU
GND
4, 21 (Exposed Pad)
Function Block Diagram
VIN
SYS
Control
Circuit
BAT
Thermal
Circuit
Sleep
Mode
ISETA
ISET
Current
Setting
VP
CC/CV/TR
/APPM
Multi Loop
Controller
R
200k
VSET
Timer
TIMER
Temperature
Sense
TS
200k
ISETL
200k
CHG
USUS
EN
ISETU
200k
Logic Control
TS_FAULT
200k
200k
PGOOD
OVP
UVLO
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2
1sec
Delay
GND
DS9519B-01 April 2011
RT9519B
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
VIN
Supply Voltage Input.
2
PGOOD
Power Good Status Output. Open-drain output.
3
CHG
Charger Status Output. Open-drain output.
4,
GN D
21 (Exposed Pad)
5
Ground. The exposed pad must be soldered to a large PCB and connected to
GND for maximum power dissipation.
ISETA
Charge Current Set Input. Connect a resistor (RISETA ) between ISETA and GND.
6
TS
Temperature Sense Input. The TS pin connects to a battery’s thermistor to
determine if the battery is too hot or too cold to charge. If the battery’s
temperature is out of range, charging is paused until it re-enters the valid range.
TS also detects whether the battery (with NTC) is present or not.
7
TIMER
Safe Charge Timer Setting.
8,9
BAT
Battery Charge Current Output.
10
EN
Charge Enable. Active Low input. 200kΩ pull low.
11
ISET
Half Charge Current Set Input. Control by external GPIO, L = ICHG1 / 2, H = ICHG1,
200kΩ pull low.
12
VP
13
ISETU
14
ISETL
15
VSET
16
TS_FAULT
17, 18, 19
20
This pin must be provided a regulated voltage from 2.95V to 3.6V by external
power.
VIN Current Limit Control Input. When ISETL = L, L = 100mA, H = 500mA,
200kΩ pull low.
VIN Current Limit Control Input. L : see ISETU, H = 1.5A, 200kΩ pull low.
Battery Regulation Set Input. Control by external GPIO. L = 4.05V, H = 4.2V,
200kΩ pull low.
TS Fault Status Output. Open-drain Output. If TS is of fault (too cold, too hot) or
VP triggers UVLO, TS_FAULT = L. If TS and VP are normal, TS_FAULT = H.
SYS
System Connect Pin. Connect this pin to System with a minimum 10μF ceramic
capacitor to GND.
USUS
VIN Suspend Control Input. H = Suspend, L = No suspend. 200kΩ pull low.
DS9519B-01 April 2011
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3
RT9519B
Absolute Maximum Ratings
z
z
z
z
z
z
z
z
z
z
z
(Note 1)
Supply Voltage, VIN ----------------------------------------------------------------------------------------------------- −0.3V to 28V
CHG, PGOOD ------------------------------------------------------------------------------------------------------------ −0.3V to 28V
Other Pins ----------------------------------------------------------------------------------------------------------------- −0.3V to 6V
CHG, PGOOD Continuous Current ---------------------------------------------------------------------------------- 20mA
BAT Continuous Current (total in two pins) (Note 2) ----------------------------------------------------------- 2.5A
Power Dissipation, PD @ TA = 25°C
WQFN-20L 3x3 ----------------------------------------------------------------------------------------------------------- 1.471W
Package Thermal Resistance (Note 3)
WQFN-20L 3x3, θJA ----------------------------------------------------------------------------------------------------- 68°C/W
WQFN-20L 3x3, θJC ------------------------------------------------------------------------------------------------------------------------------------------------ 7.5°C/W
Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------------- 260°C
Junction Temperature --------------------------------------------------------------------------------------------------- 150°C
Storage Temperature Range ------------------------------------------------------------------------------------------- −65°C to 150°C
ESD Susceptibility (Note 4)
HBM (Human Body Mode) --------------------------------------------------------------------------------------------- 2kV
MM (Machine Mode) ---------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions
z
z
z
z
(Note 5)
Supply Input Voltage Range,VIN (ISETL = H) ---------------------------------------------------------------------Supply Input Voltage Range,VIN (ISETL = L) ---------------------------------------------------------------------Junction Temperature Range -----------------------------------------------------------------------------------------Ambient Temperature Range ------------------------------------------------------------------------------------------
4.4V to 6V
4.5V to 6V
−40°C to 125°C
−40°C to 85°C
Electrical Characteristics
(VIN = 5V, VBAT = 4V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Supply Input
VIN Under Voltage Lockout
VUVLO
Threshold
VIN Under Voltage Lockout
ΔVUVLO
Hysteresis
Test Conditions
Min
Typ
Max
Unit
VIN = 0V to 4V
3.1
3.3
3.5
V
VIN = 4V to 0V
--
240
--
mV
I SYS = I BAT = 0mA, EN = L (VBAT > VREGx)
--
1
2
I SYS = IBAT = 0mA, EN = H (VBAT > VREGx)
--
0.8
1.5
VIN Supply Current
ISUPPLY
VIN Suspend Current
VBAT Sleep Leakage
Current
VIN-BAT VOS Rising
IUSUS
VIN = 5V, USUS = H
--
195
300
μA
ISLEEP
VBAT > VIN , (VIN = 0V)
--
5
15
μA
VOS_H
--
200
300
mV
VIN-BAT VOS Falling
Voltage Regulation
VOS_L
10
50
--
mV
4.3
4.4
4.5
V
4.16
4.2
4.23
V
4.01
4.05
4.08
V
120
200
System Regulation Voltage VSYS
Battery Regulation Voltage
VREG1
Battery Regulation Voltage
VREG2
APPM Regulation Voltage
ΔVAPPM
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4
I SYS = 800mA
0 to 85°C , Loading = 20mA,
When VSET = H
0 to 85°C, Loading = 20mA,
When VSET = L
VSYS − ΔVAPPM
mA
280
mV
To be continued
DS9519B-01 April 2011
RT9519B
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
DPM Regulation Voltage
VIN to VSYS MOSFET Ron
VDPM
RDS(ON)
ISETL = L
IVIN = 1000mA
4.3
--
4.4
0.2
4.5
0.35
V
Ω
BAT to VSYS MOSFET Ron
RDS(ON)
VBAT = 4.2V, ISYS = 1A
--
0.05
0.1
Ω
Re-Charge Threshold
ΔVREGCHG
Battery Regulation − Recharge
level
60
100
140
mV
ISETA Set Voltage (Fast Charge
Phase)
VISETA
VBAT = 4V, RISETA = 1kΩ
--
2
--
V
Charge Current Setting Range
ICHG
100
--
1200
mA
570
600
630
mA
285
300
315
mA
1.2
1.5
1.8
A
ISETL = L, ISETU = H
(500mA mode)
450
475
500
mA
ISETL = L, ISETU = L
(100mA Mode)
90
95
100
mA
BAT Falling
2.7
2.8
2.9
V
--
200
--
mV
Current Regulation
Charge Current Accuracy1
ICHG1
Charge Current Accuracy2
ICHG2
VIN Current Limit
IVIN
VBAT = 4V, RISETA = 1kΩ
ISET = H
VBAT = 3.8V, RISETA = 1kΩ
ISET = L
ISETL = H (1.5A Mode)
Pre-charge
BAT Pre-Charge Threshold
VPRECH
BAT Pre-Charge Threshold Hysteresis ΔVPRECH
Pre-Charge Current
ICHG_PRE
VBAT = 2V
5
10
15
%
Charge Termination Detection
Termination Current Ratio to Fast
Charge (Except USB 100 Mode)
ITERM
ISETL = L, ISETU = H
ISETL = H, ISETU = X
5
10
15
%
Termination Current Ratio to Fast
Charge (USB100 Mode)
ITERM2
ISETL = L, ISETU = L
--
3.3
--
%
CHG Pull Down Voltage
VCHG
ICHG = 5mA
--
200
--
mV
PGOOD Pull Down Voltage
VPGOOD
IPGOOD = 5mA
--
200
--
mV
TS_FAULT Pull Down Voltage
VTS_FAULT ITS_FAULT = 5mA
--
200
--
mV
EN, ISETL, USUS,
ISETU, VSET, ISET
Threshold Voltage
Logic-High
VIH
1.5
--
--
Logic-Low
VIL
--
--
0.4
---6.25
125
155
20
6.5
---6.75
°C
°C
°C
V
Login Input/Output
V
Protection
Thermal Regulation
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
Over Voltage Protection
TREG
TSD
ΔTSD
VOVP
VIN Rising
Over Voltage Protection Hysteresis
ΔVOVP
VIN = 7V to 5V, VOVP − ΔVOVP
--
100
--
mV
Output Short Circuit Detection
Threshold
VSHORT
VBAT − VSYS
--
300
--
mV
To be continued
DS9519B-01 April 2011
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5
RT9519B
Param eter
Symbol
Test Conditions
Min
Typ
Max
Unit
1440
1800
2160
s
Tim e
Pre-Charge Fault Time
t PCHG
CTIMER = 1μF (1/8 x tFCHG)
Fast charge Fault Time
t FCHG
CTIMER = 1μF
PGOOD Deglitch Time
tPGOOD
Time measured from VIN :
0Æ5V
1μs rise-time to PGOOD = L
11520
14400 17280
s
--
1
--
s
tOVP
--
50
--
μs
t PF
--
25
--
ms
Input Over Voltage Blanking
Time
Pre-Charge to Fast-Charge
Deglitch Time
Fast-Charge to Pre-Charge
Deglitch Time
Termination Deglitch Time
Recharge Deglitch Time
t FP
--
25
--
ms
t TERMI
t RECHG
---
25
100
---
ms
ms
Input Power Loss to SYS LDO
Turn-Off Delay Time
t NO_IN
--
25
--
ms
Pack T emperature Fault
Detection Deglitch Time
t TS
--
25
--
ms
Short C ircuit D eglitch Time
t SHORT
--
250
--
μs
Short C ircuit R ecovery Time
Other
VP (External used only)
VP Under Voltage Lockout
Threshold
TS Battery Detect Threshold
NTC
t SHORT-R
--
64
--
ms
2.95
--
3.6
V
--
0.8
--
V
2.75
2.85
2.95
V
Low Temperature Trip Point
VCOLD
73
74
75
% of VP
Low Temperature Trip point
Hysteresis
ΔVCOLD
--
1
--
% of VP
High Temperature Trip Point
VHOT
27
28
29
% of VP
High Temperature Trip Point
Hysteresis
ΔVHOT
--
1
--
% of VP
V VP
Falling Threshold
V TS
Rising Threshold
Falling Threshold
Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for
stress ratings. 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 for extended
periods may remain possibility to affect device reliability.
Note 2. Guraranteed by design.
Note 3. θJA is measured in natural convection at TA = 25°C on a high effective thermal conductivity four-layer test board of
JEDEC 51-7 thermal measurement standard. The measurement case position of θJC is on the exposed pad of the
package.
Note 4. Devices are ESD sensitive. Handling precaution is recommended.
Note 5. The device is not guaranteed to function outside its operating conditions.
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6
DS9519B-01 April 2011
RT9519B
Typical Operating Characteristics
Charger On/Off Control from EN
Charger On/Off Control from VIN
USB 500mA Mode
USB 500mA Mode
VEN
(5V/Div)
VCHG
(5V/Div)
VIN
(5V/Div)
V CHG
(5V/Div)
VBAT
(5V/Div)
IBAT
(500mA/Div)
VBAT
(5V/Div)
IBAT
(500mA/Div)
VIN = 5V, VBAT = Real Battery, VVP = 3.3V
VIN = 5V, VBAT = Real Battery, VVP = 3.3V
Time (25ms/Div)
Time (500ms/Div)
TS Inserted/Removed
VIN Removal
USB 500mA Mode
VCHG
(5V/Div)
IBAT
(1A/Div)
VBAT
(5V/Div)
VTS
(5V/Div)
IBAT
(500mA/Div)
V SYS
(5V/Div)
VBAT
(10V/Div)
VIN
(10V/Div)
VIN = 5V, VBAT = Real Battery,
VVP = 3.3V, RSYS = 10Ω, ISETL = H
VIN = 5V, VBAT = Real Battery, VVP = 3.3V
Time (10ms/Div)
Time (25ms/Div)
VIN Hot-plug with NTC/without Battery
VIN Hot-plug without NVC/Battery
I IN
(500mA/Div)
I IN
(500mA/Div)
VSYS
(5V/Div)
VBAT
(10V/Div)
VIN
(10V/Div)
V SYS
(5V/Div)
VBAT
(10V/Div)
VIN
(10V/Div)
VIN = 5V, VVP = 3.3V,
RSYS = 10Ω, ISETL = H
Time (100ms/Div)
DS9519B-01 April 2011
VIN = 5V, VVP = 3.3V,
RSYS = 10Ω, ISETL = H
Time (100ms/Div)
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7
RT9519B
VIN Over Voltage Protection
VIN Hot-plug with Battery
IBAT
(1A/Div)
IBAT
(1A/Div)
V SYS
(5V/Div)
VBAT
(10V/Div)
VIN
(10V/Div)
VIN
(10V/Div)
VSYS
(10V/Div)
VBAT
(10V/Div)
VIN = 5V, VVP = 3.3V, VBAT = Real Battery,
RSYS = 10Ω, ISETL = H
VIN = 5V to 15V, VBAT = Real Battery,
RSYS = 10Ω, ISETL = H
Time (500ms/Div)
Time (100ms/Div)
OVP Threshold Voltage vs. Temperature
6.52
4.48
6.50
OVP Threshold Voltage (V)
System Regulation Voltage (V)1
System Regulation Voltage vs. Temperature
4.50
4.46
4.44
4.42
4.40
4.38
4.36
4.34
4.32
VIN = 5V, VVP = 3.3V, ISYS = 0.5A
4.30
6.48
Rising
6.46
6.44
6.42
6.40
6.38
Faling
6.36
6.34
VIN = 5V, VBAT = 3.7V, VVP = 3.3V
6.32
-50
-25
0
25
50
75
100
125
-50
-25
0
VBAT
120
- VSYS Dropout Voltage vs. Temperature
455
430
405
380
355
330
305
280
255
VIN = 5V, VVP = 3.3V, ISYS = 1A
230
-50
-25
0
25
50
Temperature (°C)
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8
75
100
125
VBAT - VSYS Dropout Voltage (mV)
VIN - VSYS Dropout Voltage (mV)
VIN
480
25
50
75
100
125
Temperature (°C)
Temperature (°C)
- VSYS Dropout Voltage vs. Temperature
115
110
105
100
95
90
85
80
75
70
65
60
55
-50
VBAT = 3.7V, VVP = 3.3V, ISYS = 1A, USUS = H
-25
0
25
50
75
100
125
Temperature (°C)
DS9519B-01 April 2011
RT9519B
ICHG Thermal Regulation vs. Temperature
Battery Regulation Voltage vs. Temperature
4.30
Battery Regulation Voltage (V)1
I CHG Thermal Regulation (mA)1
500
450
400
350
300
250
200
150
100
50
VIN = 5V, VBAT = 3.7V, VVP = 3.3V
0
4.28
4.26
4.24
4.22
4.20
4.18
4.16
4.14
4.12
VIN = 5V, VVP = 3.3V
4.10
-50
-25
0
25
50
75
100
125
-50
-25
25
50
75
100
125
Fastcharge Current vs. Battery Voltage
Precharge Current vs. Battery Voltage
140
800
120
750
Fastcharge Current (mA)1
Precharge Current (mA)
0
Temperature (°C)
Temperature (°C)
100
80
60
40
20
700
650
600
550
500
450
VIN = 5V, VVP = 3.3V, RISETA = 0.6kΩ, ISETL = H
VIN = 5V, VVP = 3.3V, RISETA = 1kΩ, ISETL = H
0
400
2
2.2
2.4
2.6
Battery Voltage (V)
DS9519B-01 April 2011
2.8
3
3
3.2
3.4
3.6
3.8
4
4.2
Battery Voltage (V)
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9
RT9519B
Applications Information
The RT9519B is a fully integrated single-cell Li-ion battery
charger ideal for portable applications. The internal thermal
feedback circuitry regulates the die temperature to optimize
the charge rate for all ambient temperatures. Other features
include under voltage protection and over voltage
protection.
Pre-charge Mode
When the output voltage is lower than 2.8V, the charging
current will be reduce to a fast-charge current ratio set by
RISETA to protect the battery life time.
Fast-charge Mode
When the output voltage is higher than 3V, the charging
current will be equal to the fast-charge current set by
RISETA.
Constant Voltage Mode
When the output voltage is near 4.2V, and the charging
current fall below the termination current, after a deglitch
time check of 25ms, the charger will become disabled
and CHG will go from L to H.
For example the system load current may have activated
the APPM loop which reduces the available charging
current. the device has entered thermal regulation because
the IC junction temperature has exceeded TREG.
During each of these events, if 3V < VBAT < 4.1V, the
internal charging time is slowed down proportionately to
the reduction in charging current. However, once the
duration exceed the fault time, the CHG output will flash
at approximately 2Hz to indicate a fault condition and the
charge current will be reduced to about 1mA.
2V
tFCHG_true = tFCHG ×
VISETA
tFCHG_true : modified timer in fast
tFCHG : original timer in fast charger
tFCHG = 14400 sec × (
CTIMER
)
1μ F
tFCHG
8
: timer in pre-charge
tPCHG =
tPCHG
Time fault release methods :
(1) Re-plug power
Re-charge Mode
(2) Toggle EN
When the chip is in charge termination mode, the charging
current will gradually go down to zero. However, once the
voltage of the battery drops to below 4.1V, there will be a
deglitch time of 100ms and then the charging current will
resume again.
(3) Enter/exit suspend mode
Charging Current Decision
The charge current can be set according to the following
equations :
(4) Remove Battery
(5) OVP
If ISET = H (for ICHG1)
timer = tFCHG
If ISET = L (for ICHG2)
timer = 2 x tFCHG
If ISET = H (for ICHG1 )
ICHG_FAST =
VISETA
× 300
RISETA
If ISET = L (for ICHG2 )
ICHG_FAST =
VISETA
× 150
RISETA
ICHG_PRE = 10% × ICHG_FAST
Power Good
VIN Power Good ( PGOOD = L)
Input State
VIN < VUVLO
VUVLO < VIN < VBAT + VOS_H
VBAT + VOS_H < VIN < VOVP
VIN > VOVP
PGOOD Output
High Impedance
High Impedance
Low Impedance
High Impedance
Time Fault
During the fast charge phase, several events may increase
the charging time.
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10
DS9519B-01 April 2011
RT9519B
Charge State Indicator
Charge State
CHG Output
Charging
Charging Suspended by
Thermal Loop
Safety Timers Expired
Low
(for first charge cycle)
2Hz Flash
Charging Done
Recharging after
Termination
IC Disabled or no Valid
Input Power
From (1), (2)
R
− RHOT
R1 = COLD
2.457
R2 = 0.389 × R1− RHOT
If R2 < 0
RCOLD
= 0.74
RCOLD + R1
High Impedance
(3)
From (3)
R1 =
RCOLD
− RCOLD
0.74
Battery Pack Temperature Monitoring
The battery pack temperature monitoring function can be
realized by connecting the TS pin to an external Negative
Temperature Coefficient (NTC) thermistor to prevent over
temperature condition. Charging is suspended when the
voltage at the TS pin is out of normal operating range. The
internal timer is then paused, but the value is maintained.
When the TS pin voltage returns back to normal operating
range, charging will resume and the safe charge timer will
continue to count down from the point where it was
suspended. Note that although charging is suspended due
to the battery pack temperature fault, the CHG pin will
continue to remain low and indicate charging.
VP
VP
0.74 x VP -
R1
TS
+
0.28 x VP
+
When EN is low, the charger turns on. When EN is high,
the charger turns off. EN is pulled low for initial condition.
VIN input Current Limit
ISETL
ISETU
L
L
H
L
H
X
VIN Input Current
Lim it
95mA
475mA
1.5A
Suspend Mode
Set USUS = H, and the charge will enter Suspend Mode.
In the Suspend Mode, CHG is in high impedance and
IUSUS(MAX) < 300μA.
Power Switch
Too Cold
For the RT9519B, there are three power scenarios:
-
R2
Charge Enable
Too Hot
(1)When a battery and an external power supply (USB or
adapter) are connected simultaneously :
RNTC
Too Hot Temperature
If the system load requirements exceed that of the input
current limit, the battery will be used to supplement the
current to the load. However, if the system load
requirements are less than that of the input current limit,
the excess power from the external power supply will be
used to charge the battery.
RHOT = RNTC
(2)When only the battery is connected to the system :
Figure 1
Too Cold Temperature
RCOLD = RNTC
R2 + RCOLD
= 0.74
RCOLD + R1 + R2
R2 + RHOT
= 0.28
RHOT + R1 +R2
DS9519B-01 April 2011
The battery provides the power to the system.
(1)
(2)
(3)When only an external power supply is connected to
the system :
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11
RT9519B
The external power supply provides the power to the
system.
While in supplement mode, there is no battery supplement
current regulation. However, a built in short circuit
protection feature is available to prevent any abnormal
current situations. While the battery is supplementing the
load, if the difference between the battery and SYS voltage
becomes more than the short circuit threshold voltage,
SYS will be disabled. After a short circuit recovery time,
tSHORT_R, the counter will be restarted. In supplement
mode, the battery termination function is disabled. Note
that for the battery supply mode exit condition, VBAT −
VSYS < 0V.
Input DPM Mode
For the RT9519B, the input voltage is monitored when
the USB100 or USB500 is selected. If the input voltage is
lower than VDPM, the input current limit will be reduced to
stop the input voltage from dropping any further. This can
prevent the IC from damaging improperly configured or
inadequately designed USB sources.
APPM Mode
Thermal Regulation and Thermal Shutdown
Once the sum of the charging and system load currents
becomes higher than the maximum input current limit,
the SYS pin voltage will be reduced. When the SYS pin
voltage is reduced to the VAPPM, the RT9519B will
automatically operate in APPM mode. In this mode, the
charging current is reduced while the SYS current is
increased to maintain system output. In APPM mode,
the battery termination function is disabled.
The RT9519B provides a thermal regulation loop function
to monitor the device temperature. If the die temperature
rises above the regulation temperature, TREG, the charge
current will automatically be reduced to lower the die
temperature. However, in certain circumstances (such as
high VIN, heavy system load, etc.) even with the thermal
loop in place, the die temperature may still continue to
increase. In this case, if the temperature rises above the
thermal shutdown threshold, TSD, the internal switch
between VIN and SYS will be turned off. The switch
between the battery and SYS will remain on, however, to
allow continuous battery power to the load. Once the die
temperature decreases by ΔTSD, the internal switch
between VIN and SYS will be turned on again and the
device returns to normal thermal regulation.
Battery Supplement Mode Short Circuit Protect
In APPM mode, the SYS voltage will continue to drop if
the charge current is zero and the system load increases
beyond the input current limit. When the SYS voltage
decreases below the battery voltage, the battery will kick
in to supplement the system load until the SYS voltage
rises above the battery voltage.
Charging Profile
4.16 to 4.2 to 4.23V
-40 to 85°C
Battery Voltage
Charging Current
VRECH
VPRECH
ISETL = L, ISETU = H
If
ISETL = H, ISETU = X
ITERMI = 10% x ICHG_FAST
If ISETL = L, ISETU = L
ITERMI = 3.3% x ICHG_FAST
ICHG_PRE = 10% x ICHG_FAST
ITERM
ITERM2
Time
Figure 2
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12
DS9519B-01 April 2011
RT9519B
APPM Profile
1.5A Mode :
VIN 5V
VSYS 4.4V
VAPPM 4.2V
VBAT 4.0V
3A
2A
IBAT
1A
ISYS
0
IVIN -1A
-2A
-3A
T1
T2
T3
T4
T5
T6
T7
ISYS
VSYS
IVIN
IBAT
T1, T7
0
SYS Regulation Voltage
CHG_MAX
CHG_MAX
T2, T6
< IVIN_OC − CHG_MAX
SYS Regulation Voltage
ISYS + CHG_MAX
CHG_MAX
Auto Charge Voltage Threshold
VIN _OC
V IN_OC − ISYS
VBAT − IBAT x RD S(ON)
VIN _OC
ISYS−IVIN_OC
T3, T5
> IVIN_OC − CHG_MAX
< IVIN_OCs
T4
> IVIN_OC
USB 500mA Mode :
VUSB
5V
VSYS
4.4V
VAPPM
4.2V
VBAT
4.0V
0.75A
0.5A
IBAT 0.25A
0
ISYS
IUSB -0.25A
-0.5A
-0.75A
T1
T2
T3
T4
T5
T6
T7
ISYS
VSYS
IUSB
IBAT
T1, T7
0
SYS Regulation Voltage
CHG_MAX
CHG_MAX
T2, T6
< IVIN_OC (USB) − CHG_MAX
SYS Regulation Voltage
T3, T5
T4
> IVIN_OC (USB) − CHG_MAX
< IVIN_OC (USB)
> IVIN_OC (USB)
DS9519B-01 April 2011
ISYS + CHG_MAX
CHG_MAX
Auto Charge Voltage
Threshold
IVIN_OC (USB)
IVIN_OC (USB) − ISYS
VBAT − IBAT x RDS(ON)
IVIN_OC (USB)
ISYS − IVIN_OC (USB)
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13
RT9519B
VSET vs VREG , ISET vs ICHG
VSET
4.16 to 4.2 to 4.23V
VREG
4.01 to 4.05 to 4.08V
ISET
ICHG +/-5%
ICHG
0.5 x ICHG +/-5%
For JEITA Battery Temperature Standard :
CV regulation voltage will change at the following battery Temp ranges
0°C to 10°C and 45°C to 60°C
CC regulation current will change at the following battery Temp ranges
0°C to 10°C and 45°C to 60°C
4.16 to 4.2 to 4.23V
4.01 to 4.05 to 4.08V
4.01 to 4.05 to 4.08V
0°C
45°C
10°C
60°C
Temperature +/- 2°C
ICHG +/- 5%
0.5 x ICHG +/- 5%
0.5 x ICHG +/- 5%
Temperature +/- 2°C
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14
DS9519B-01 April 2011
RT9519B
RT9519B Operation State Digram for Charging
Fast-Charge State
If ISET = H
ICHG_FAST = (VISETA / RISETA) x 300
If ISET = L
ICHG_FAST = (VISETA / RISETA) x 150
Yes
VBAT > 3V
No
VIN – VBAT
> VOS_H
Yes
Pre-Charge State
ICHG_PRE =
Sleep State
If VSET = H
Check VBAT > 4.1V
If VSET = L
Check V BAT > 3.95V
No
10% x ICHG_FAST
Yes
No
Time > tFCHG
Yes
No
Time > tPCHG
Standby State
ISETL = L & ISETU = H
ISETL = H & ISETU = X
Check ICHG < 10% x ICHG_FAST
If ISETL = L & ISETU = L
Check ICHG < 3.3% x ICHG_FAST
If
Yes
No
Timer-Out State
CHG = flash 2Hz
& ICHG to 1mA
Yes
No
Yes
VUVLO< VIN < VOVP
& EN = L
&USUS = L
Re-Charge State
CHG = High
impedance
Charger
Disable
Time > tTERMI = 25msec
Yes
Yes
If VSET = H
Check VBAT < 4.1V
If VSET = L
Check VBAT < 3.95V
Any State
or VIN < VUVLO,
Charge Done State
CHG = High impedance
& ICHG = 0A
or VIN > VOVP,
Or VIN - VBAT < VOS_H
or USUS = H
or EN = H
No
Operation State Digram for TS PIN
Any State
No
74% x VVP < VTS < 2.85V
Or VTS < 28% x VVP
No
VTS > 2.85V
Yes
Yes
TS fault State
ICHG = 0A
Keep CHG state
DS9519B-01 April 2011
Battery Remove State
ICHG = 0A
CHG = High impedance
Reset timer and CHG
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15
RT9519B
Thermal Considerations
Layout 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 :
The RT9519B 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.
PD(MAX) = (TJ(MAX) − TA) / θJA
A short connection is highly recommended. The following
guidelines should be strictly followed when designing a
PCB layout for the RT9519B.
`
Input and output capacitor should be placed close to
the IC and connected to ground plane. The input trace
on the PCB should be placed far away from 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 RISETA should be isolated from other
noisy traces. A short wire is recommended to prevent
EMI and noise coupling.
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
For recommended operating condition specifications of
the RT9519B, the maximum junction temperature is 125°C
and TA is the ambient temperature. The junction to ambient
thermal resistance, θJA, is layout dependent. For WQFN20L 3x3 packages, the thermal resistance, θJA, is 68°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) / (68°C/W) = 1.471W for
WQFN-20L 3x3 package
The maximum power dissipation depends on the operating
ambient temperature for fixed T J(MAX) and thermal
Maximum Power Dissipation (W)1
resistance, θJA. For the RT9519B package, the derating
curve in Figure 3 allows the designer to see the effect of
rising ambient temperature on the maximum power
dissipation.
1.6
Four-Layer PCB
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 3. Derating Curves for RT9519B Package
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16
DS9519B-01 April 2011
RT9519B
R4
GND should be connected
to a strong ground plane for
heat sinking and noise
protection.
CSYS
GND
SYS
CIN
R3 R2
20 19 18 17 16
VIN
PGOOD
CHG
GND R
GND
ISETA
ISETA
1
15
2
14
GND
3
4
13
21
5
12
11
7
8
CTIMER
VSET
ISETL
ISETU
VP
ISET
9 10
TS
TIMER
BAT
BAT
EN
6
The RISETA connection
copper area should be
minimized and kept far away
from noise sources.
Connect the Exposed Pad
to a ground plane.
USUS
SYS
SYS
SYS
TS_FAULT
Place CIN near The IC to
improve performance.
CBAT
GND
R1
CVP
TS
NTC
GND
Figure 4. PCB Layout Guide
DS9519B-01 April 2011
www.richtek.com
17
RT9519B
Outline Dimension
1
1
2
2
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
0.150
0.250
0.006
0.010
D
2.900
3.100
0.114
0.122
D2
1.650
1.750
0.065
0.069
E
2.900
3.100
0.114
0.122
E2
1.650
1.750
0.065
0.069
e
L
0.400
0.350
0.016
0.450
0.014
0.018
W-Type 20L QFN 3x3 Package
Richtek Technology Corporation
Richtek Technology Corporation
Headquarter
Taipei Office (Marketing)
5F, No. 20, Taiyuen Street, Chupei City
5F, No. 95, Minchiuan Road, Hsintien City
Hsinchu, Taiwan, R.O.C.
Taipei County, Taiwan, R.O.C.
Tel: (8863)5526789 Fax: (8863)5526611
Tel: (8862)86672399 Fax: (8862)86672377
Email: [email protected]
Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit
design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be
guaranteed by users when integrating Richtek products into any application. No legal responsibility for any said applications is assumed by Richtek.
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18
DS9519B-01 April 2011