AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 1
www.analogictech.com
General Description
The AAT3783 BatteryManager™ is a single-cell Lithium-
Ion (Li-Ion)/Li-Polymer battery charger IC, designed to
operate from USB ports, AC adapter inputs, or from a
charger adapter up to an input voltage of 6.5V. For
increased safety, the AAT3783 also includes over-voltage
input protection (OVP) up to 28V.
The AAT3783 precisely regulates battery charge voltage
and current for 4.2V Li-Ion/Polymer battery cells through
an extremely low RDS(ON) switch. When charged from an
adapter or a USB port, the battery charging current can
be set by an external resistor up to 1A. In the case of an
over-voltage condition in excess of 6.5V, a series switch
opens preventing damage to the battery and charging
circuitry. With the addition of an external resistor the
OVP trip point can be programmed to a level other than
the factory set value of 6.5V. In the case of an OVP con-
dition a fault flag is activated.
Battery charge state is continuously monitored for fault
conditions. In the event of an over-current, battery over-
voltage, short-circuit or over-temperature failure, the
device will automatically shut down, thus protecting the
charging device, control system and the battery under
charge. A status monitor output pin is provided to indi-
cate the battery charge status by directly driving an
external LED. An open-drain power-source detection
output (ADPP) is provided to report the power supply
status.
The AAT3783 comes in a thermally enhanced, space-
saving, Pb-free 16-pin 3x4 mm TDFN package and is
specified for operation over the -40°C to +85°C tem-
perature range.
Features
• USB or AC Adapter System Power Charger
• Programmable from 100mA to 1A Max
• 4.0V ~ 7.5V Input Voltage Range
Over-Voltage Input Protection up to 28V
• High Level of Integration with Internal:
Charging Device
Reverse Blocking Diode
Current Sensing
• Digital Thermal Regulation
• Charge Current Programming (ISET)
• Charge Termination Current Programming (TERM)
• Charge Timer (CT)
• Battery Temperature Sensing (TS)
• TS Pin Open Detection
• Automatic Recharge Sequencing
• No Trickle Charge Option Available
• Full Battery Charge Auto Turn Off / Sleep State /
Charge Termination
• Automatic Trickle Charge for Battery Pre-conditioning
• Battery Over-Voltage and Over-Current Protection
•
Emergency Thermal Protection
• Power On Reset
• 16-pin 3x4mm TDFN Package
Applications
• Bluetooth™ Headsets, Headphones, Accessories
• Digital Still Cameras
• Mobile Phones
• MP3 Players
• Personal Data Assistants (PDAs)
• Other Li-Ion/Polymer Battery Powered Devices
Typical Application
10μF
BATT-
VIN
Battery
Pack
BATT+
RTERM
Enable Charging ENCHR
TERM
GND
BAT
STAT
RSET
ISET
IN
FLT
INCHR TEMP
CT
TS
ENOVP
Enable OVP
CT
OVP
2.2μF
BATS
ADPP
IN
AAT3783
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
2 3783.2008.08.1.2
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
2 3783.2008.08.1.2
www.analogictech.com
Pin Descriptions
Pin Number Name Type Function
1 INCHR I/O Internal connection between the output of the OVP stage and the input of the battery
charger. Decouple with 2.2F capacitor.
2BATSI
Battery sense pin. Connect directly to the battery's + terminal. If not used, BATS
must be connected to BAT.
3 BAT O Connect to Lithium-Ion battery.
4 TS I/O Battery temperature sense pin.
5ENOVP I Active low enable for OVP stage.
6 OVP I Over-voltage protection threshold pin. Leave open for the default 6.5V setting; con-
nect to a resistor to adjust the OVP setting (see Application Information).
7 FLT O Over-voltage fault fl ag, open drain.
8 STAT O Charge status pin, open drain.
9 ADPP O Input power-good (USB port/adapter present indicator) pin, open-drain.
10 CT I Charge timer programming input pin (no timer if grounded).
11 ENCHR I Active high enable pin (with internal pull-down) for charging circuitry.
12 TERM I Charge termination current programming input pin (internal default 10% termina-
tion current if TERM is open).
13 GND I/O Connect to power ground.
14 ISET I Charge current programming input pin.
15, 16 IN I Input from USB port/ adapter connector.
Pin Configuration
TDFN34-16
(Top View)
BAT
TS
ENOVP
INCHR
BATS
3
OVP
FLT
STAT
ISET
GND
TERM
IN
IN
ENCHR
CT
ADPP
4
5
1
EP1
EP2
2
6
7
8
14
13
12
16
15
11
10
9
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 3
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 3
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Absolute Maximum Ratings1
Symbol Description Value Units
VIN IN continuous 30 V
VINCHR Charger IN continuous -0.3 to 7.5 V
VFLT Fault fl ag continuous -0.3 to +30 V
VNBAT, STAT, ADPP, EN, ISET, TS, ENOVP, OVP -0.3 to VINCHR + 0.3 V
TJOperating Junction Temperature Range -40 to 150 °C
TLEAD Maximum Soldering Temperature (at Leads) 300 °C
Thermal Information2
Symbol Description Value Units
θJA Maximum Thermal Resistance (TDFN 3x4) 50 °C/W
PDMaximum Power Dissipation 2 W
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions
specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Mounted on a FR4 board.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
4 3783.2008.08.1.2
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
4 3783.2008.08.1.2
www.analogictech.com
Electrical Characteristics1
VIN = 5V, TA = -40°C to +85°C; unless otherwise noted, typical values are at TA = 25°C.
Symbol Description Conditions Min Typ Max Units
Operation
VIN_MAX Input Over-Voltage Protection Range 28 V
VIN Normal Operating Input Voltage Range 4.0 7.5 V
Over-Voltage Protection
VUVLO
Under-Voltage Lockout Threshold Rising Edge 3 V
UVLO Hysteresis 60 mV
IQOperating Quiescent Current VIN = 5V, ENOVP = 0V, IOUT = 0,
ENCHG = 0V 30 50 A
ISD(OFF) Shutdown Supply Current ENOVP = VIN = 5.5V, VOUT = 0V,
ENCHG = 0V 48A
VOVPT Over-Voltage Protection Trip Voltage Rising Edge, OVP = Not Connected 6.5 V
Battery Charger
VUVLO
Under-Voltage Lockout Threshold Rising Edge 3 4 V
UVLO Hysteresis 150 mV
VADPP_TH
Adapter Present Indicator Threshold
Voltage, VIN - VBAT
VIN > VUVLO 60 150 mV
IOP Operating Current Charge Current = 100mA,
ENOVP = 0V, ENCHG = VIN
0.5 1 mA
ISHUTDOWN Shutdown Mode Current VBAT = 4.25V, ENOVP = ENCHG = 0V20.4 1 A
IBAT Leakage Current from BAT Pin VBAT = 4V, ENOVP = VIN 0.4 2 A
Voltage Regulation
VBAT_EOC Output Charge Voltage Regulation 4.158 4.20 4.242 V
ΔVCH/VCH Output Charge Voltage Tolerance 0.5 %
VMIN Preconditioning Voltage Threshold (Option available for no trickle charge) 2.5 2.6 2.7 V
VRCH Battery Recharge Voltage Threshold VBAT_EOC -
0.1 V
Current Regulation
ICC_RANGE Charge Current Programmable Range 100 1000 mA
ICH_CC Constant-Current Mode Charge Current VBAT = 3.6V -10 10 %
VISET ISET Pin Voltage 2V
KISET Charge Current Set Factor: ICH_CC/IISET Constant Current Mode, VBAT = 3.6V 800
VTERM TERM Pin Voltage RTERM = 13.3kΩ0.2 V
ICH_TRK Trickle Charge Current 51015
%
ICH_CC
ICH_TERM Charge Termination Threshold Current TERM Pin Open 5 10 15 %
ICH_CC
RTERM = 13.3 kΩ, ICH_CC ≥ 800mA 8 10 12 %
Battery Charging Device
RDS(ON) Total ON Resistance (IN to BAT) VIN = 5V, IOUT = 1A 550 mΩ
1. The AAT3783 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization and correla-
tion with statistical process controls.
2. Current into charge.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 5
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 5
www.analogictech.com
Electrical Characteristics1
VIN = 5V, TA = -40°C to +85°C; unless otherwise noted, typical values are at TA = 25°C.
Symbol Description Conditions Min Typ Max Units
Logic Control
VEN(H) Input High Threshold 1.6 V
VEN(L) Input Low Threshold 0.4 V
VSTAT Output Low Voltage STAT Pin Sinks 4mA 0.4 V
ISTAT STAT Pin Current Sink Capability 8mA
VADDP Output Low Voltage ADPP Pin Sinks 4mA 0.4 V
IADPP ADPP Pin Current Sink Capability 8mA
VFLT Output Low Voltage FLT Pin Sinks 1mA 0.4 V
IFLT FLT Pin Current Sink Capability 5mA
TBLK_FLT FLT Blanking Time From De-assertion of OV 5 10 15 ms
TD_FLT FLT Assertion Delay Time from Over-Voltage From Assertion of OV 1 s
TRESP_OV Over-Voltage Response Time VIN Rise to 7V from 5V in 1ns 1 s
TOVPON OVP Turn-On Delay Time Charging current = 500mA,
CINCHR = 1F10 ms
TOVPR OVP Turn-On Rise Time Charging current = 500mA,
CINCHR = 1F1ms
TOVPOFF OVP Turn-Off Delay Time Charging current = 500mA,
CINCHR = 1F6s
Battery Protection
VBOVP Battery Over-Voltage Protection Threshold 4.4 V
IBOCP Battery Over-Current Protection Threshold 105 % ICH_CC
TC Trickle Plus Constant Current Mode Timeout CCT = 100nF, VIN = 5V 3 Hour
TK Trickle Timeout CCT = 100nF, VIN = 5V 25 Minute
TV Constant Voltage Mode Time Out CCT = 100nF, VIN = 5V 3 Hour
ITS Current Source from TS Pin 69 75 81 A
TS1 TS Hot Temperature Fault Threshold 316 331 346 mV
Hysteresis 25
TS2 TS Cold Temperature Fault Threshold 2.30 2.39 2.48 V
Hysteresis 25 mV
TLOOP_IN Thermal Loop Entering Threshold 115 ºC
TLOOP_OUT Thermal Loop Exiting Threshold 85 ºC
TREG Thermal Loop Regulation 100 ºC
TSHDN Chip Thermal Shutdown Temperature Threshold 140 ºC
Hysteresis 15
1. The AAT3783 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization and correla-
tion with statistical process controls.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
6 3783.2008.08.1.2
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
6 3783.2008.08.1.2
www.analogictech.com
Typical Characteristics
Constant Charging Current
vs. Set Resistor Values
RSET (mA)
Constant Charging Current (mA)
1
10
100
1000
10000
1 10 100 100
0
Battery Charging Current
vs. Battery Voltage
Battery Voltage (V)
Charging Current (mA)
0
200
400
600
800
1000
1200
2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5
RSET = 1.62kΩ
RSET = 2kΩ
RSET = 3.24kΩ
RSET = 8.06kΩ
End of Charge Regulation Tolerance vs. Input Voltage
(VBAT_EOC = 4.2V)
Input Voltage (V)
ΔVBAT_EOC/VBAT_EOC (%)
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
4.5 5 5.5 6 6.5 7 7.5
End of Charge Voltage vs. Temperature
Temperature (°C)
VEOC (%)
4.17
4.18
4.19
4.20
4.21
4.22
4.23
-40 -15 10 35 60 85
Battery Recharge Voltage Threshold
vs. Temperature
Temperature (°C)
Recharge Voltage (%)
4.04
4.06
4.08
4.1
4.12
4.14
4.16
-40 -15 10 35 60 85
Preconditioning Charge Current
vs. Input Voltage
Input Voltage (V)
ICH_TRK (mA)
0
20
40
60
80
100
120
140
4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5
RSET = 1.62kΩ
RSET = 2kΩ
RSET = 3.24kΩ
RSET = 8.06kΩ
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 7
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 7
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Typical Characteristics
Preconditioning Charge Current vs. Temperature
(RSET = 8.06kΩ; ICH_CC = 200mA)
Temperature (°C)
Preconditioning Charge Current (mA)
17
18
19
20
21
22
23
-40 -15 10 35 60 8
5
Preconditioning Voltage Threshold
vs. Temperature
Temperature (°C)
VMIN (V)
2.54
2.56
2.58
2.60
2.62
2.64
2.66
-40 -15 10 35 60 8
5
Constant Charging Current vs. Input Voltage
(RSET = 1.62kΩ
Ω
)
Input Voltage (V)
Constant Charging Current (mA)
700
800
900
1000
1100
1200
4 4.5 5 5.5 6 6.5 7 7.5
VBAT = 3.3V
VBAT = 3.6V
VBAT = 3.9V
VBAT = 4.1V
Total Resistance vs. Input Voltage
(IN to BAT)
Input Voltage (V)
RDS(ON) (mΩ
Ω
)
400
450
500
550
600
650
700
750
800
3.6 3.8 4 4.2 4.4 4.6 4.8 5
85°C
25°C
-40°C
Temperature Sense Too Hot Threshold
vs. Temperature
Temperature (°C)
Temperature Sense Threshold
Voltage (TS1) (mV)
325
327
329
331
333
335
337
339
-40 -15 10 35 60 85
Temperature Sense Too Cold Threshold
vs. Temperature
Temperature (°C)
Temperature Sense Threshold
Voltage (TS2) (mV)
2.375
2.380
2.385
2.390
2.395
2.400
-40 -15 10 35 60 8
5
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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Typical Characteristics
Temperature Sense Output Current
vs. Temperature
Temperature (°C)
ITS (mV)
68
70
72
74
76
78
-40 -15 10 35 60 85
CT Pin Capacitance vs. Counter Timeout
Time (h)
Capacitance (µF)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Preconditioning Timeout
Preconditioning + Constant Current
Timeout or Constant Voltage Timeout
Operating Current vs. ISET Resistor
RSET (kΩ)
IOP (mA)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1 10 100 1000
Constant current mode
Preconditioning mode
Termination Current to Constant Current Ratio
vs. Termination Resistance
ITERM Resistance (kΩ)
ICH_TERM/ICH_CC (%)
0
10
20
30
40
50
0102030405060
Input Low Threshold vs. Input Voltage
Input Voltage (V)
VEN(L) (V)
0.4
0.6
0.8
1.0
1.2
1.4
1.6
4 4.5 5 5.5 6 6.5 7 7.5
25°C
-40°C
85°C
Input High Threshold vs. Input Voltage
Input Voltage (V)
VEN(H) (V)
0.4
0.6
0.8
1.0
1.2
1.4
1.6
4 4.5 5 5.5 6 6.5 7 7.5
25°C
-40°C
85°C
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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Typical Characteristics
FLT Blanking Time
Time (2ms/div)
Input Voltage (V)
FLT Voltage (V)
-4
-2
0
2
4
6
8
10
12
0
2
4
6
OVP Trip Point vs. Temperature
Temperature (°C)
VOVPTRIP Error (%)
-0.20
-0.15
-0.10
-0.05
0.00
0.05
-40 -15 10 35 60 8
5
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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Functional Description
The AAT3783 is a high performance battery charger
designed to charge single cell Lithium-Ion or Polymer
batteries with up to 1000mA of current from an external
power source. It is a stand-alone charging solution, with
just one external component required (two more for
options) for complete functionality. Also included is input
voltage protection (OVP) to up to +28V. OVP consists of
a low resistance P-channel MOSFET in series with the
charge control MOSFET, and also consists of under-volt-
age lockout protection, over-voltage monitor, and fast
shut-down circuitry with a fault output flag.
Battery Charging Operation
Figure 1 illustrates the entire battery charging profile or
operation, which consists of three phases:
1. Preconditioning (Trickle) Charge
2. Constant Current Charge
3. Constant Voltage Charge
Battery Preconditioning
Battery charging commences only after the AAT3783
checks several conditions in order to maintain a safe
charging environment. The input supply must be above
the minimum operating voltage (VUVLO) and the enable
pin must be high. When the battery is connected to the
BAT pin, the AAT3783 checks the condition of the battery
and determines which charging mode to apply. If the
battery voltage is below the preconditioning voltage
threshold, VMIN, then the AAT3783 begins precondition-
ing the battery cell (trickle charging) by charging at 10%
of the programmed constant current. For example, if the
programmed current is 500mA, then the preconditioning
mode (trickle charge) current is 50mA. Battery cell pre-
conditioning (trickle charging) is a safety precaution for
deeply discharged cells and will also reduce the power
dissipation in the internal series pass MOSFET when the
input-output voltage differential is at the greatest poten-
tial.
Functional Block Diagram
Charge
Control
Current
Compare
Reverse Blocking
Constant
Current
BAT
ISET
UVLO
Over
Temp.
Protect
Power
Detection
STAT
GND
Thermal
Loop
ADPP
Charge
Status
OVP
Sense
and
Control
ENOVP
IN
FLT
ENCHR
INCHR
IN
BAT S
CV/ Pre -
Charge
CT
TS
TERM
OVP
Over-Current
Protection
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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Constant Current Charging
Battery cell preconditioning continues until the battery
voltage reaches the preconditioning voltage threshold,
VMIN. At this point, the AAT3783 begins constant current
charging. The current level for this mode is programmed
using a single resistor from the ISET pin to ground. The
programmed current can be set at a minimum 100mA
up to a maximum of 1A.
Constant Voltage Charging
Constant current charging will continue until such time
that the battery voltage reaches the voltage regulation
point, VBAT_EOC. When the battery voltage reaches VBAT_EOC,
the AAT3783 will transition to constant voltage mode.
The regulation voltage is factory programmed to a nom-
inal 4.2V and will continue charging until the charge
termination current is reached.
Charge Status Output
The AAT3783 provides battery charge status via a status
pin. This pin is internally connected to an N-channel
open-drain MOSFET, which can be used drive an external
LED. The status pin can indicate the following condi-
tions:
Event Description STATUS
No battery charging activity OFF
Battery charging via adapter or USB port ON
Charging completed OFF
Table 1: LED Status Indicator.
Thermal Considerations
The actual maximum charging current is a function of
the charge adapter input voltage, the battery charge
state at the moment of charge, the ambient tempera-
ture, and the thermal impedance of the package. The
maximum programmable current may not be achievable
under all operating parameters.
Over-Voltage Protection
In normal operation, a P-channel MOSFET acts as a
slew-rate controlled load switch, connecting and discon-
necting the power supply from IN to INCHR. A low resis-
tance MOSFET is used to minimize the voltage drop
between the voltage source and the charger and to
reduce the power dissipation. When the voltage on the
input exceeds the over-voltage trip point (internally set
by the factory or externally programmed by a resistor
connected to the OVP pin), the device immediately turns
off the internal P-channel FET which disconnects the
charger from the abnormal input voltage, therefore pre-
venting any damage to the charger. Simultaneously, the
fault flag is raise, alerting the system.
If an over-voltage condition is applied at the time of the
device enable, then the switch will remain OFF.
OVP Under-Voltage Lockout (UVLO)
The AAT3783 OVP circuitry has a fixed 3V under-voltage
lockout level (UVLO). When the input voltage is less than
the UVLO level, the MOSFET is turned off. 100mV of
hysteresis is included to ensure circuit stability.
Constant Current
Charge Phase
Constant Voltage
Charge Phase
Preconditioning
Trickle Charge
Phase
Charge Complete Voltage
Constant Current Mode
Voltage Threshold
Regulated Current
Trickle Charge and
Termination Threshold
I = CC / 10
I = Max CC
Figure 1: Current vs. Voltage Profile during Charging Phases.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
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Over-Current Protection
The AAT3783 over-current protection provides fault-
condition protection that limits the charge current to
approximately 1.6A under all conditions, even if the ISET
pin gets shorted to ground.
FLT Blanking Time
The FLT output is an active-low open-drain fault (OV)
reporting output. A pull-up resistor should be connected
from FLT to the logic I/O voltage of the host system. FLT
will be asserted immediately an over-voltage fault occurs
(only about a 1s inherited internal circuit delay). A
10ms blanking is applied to the FLT signal prior to de-
assertion.
Enable / Disable
The AAT3783 provides an enable function to control the
OVP stage and charger on and off independently.
ENOVP is an active-low enable input. ENOVP is driven
low, connected to ground, or left floating for normal
device operation. Taking ENOVP high turns off the
MOSFET of the OVP stage. In the case of an over-voltage
or UVLO condition, toggling ENOVP will not override the
fault condition and the switch will remain off.
OVP Turn-On Delay Time
On initial power-up, if VIN < UVLO or if VOVP > 6.5V the
PMOS is held off. If UVLO < VIN, VOVP < 6.5V, and ENOVP
is low, the device enters startup after a 10ms internal
delay.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
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AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
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System Operation Flow Chart
V
CH>V
BAT
V
MIN>V
BAT
Shut Down
Mode
Shut Down
Mode
I
BAT
> I
MIN
No
No
Charge
Completed
Charge
Completed
Recharge
Test
V
RCH
> V
BAT
Yes
Yes
Device Temp.
Monitor
TJ>110 C
Yes
ADP
Voltage
S
ADP > V
ADPP
No
Preconditioning
Test
VMIN>VBAT
Current Phase Test
VIN>VBAT_EOC
Voltage Phase Test
IBAT>ITERM
Shut Down
Mode
Shutdown
Mode
No
No
Charge
Completed
Charge
Completed
Recharge
Test
VRCH > VBAT
Yes
Enable
Expire
Yes
Device Temp.
Monitor
T
J>115 C
Yes
Fault
No
Yes
No
Power Select
Power Input
Voltage
VIN>VUVLO
Power Select
Fault
Condition Monitoring
OV, OT,
VTS1<TS<VTS2
Sleep
Mode
Sleep
Mode
Sleep
Power On
Reset
Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Preconditioning
(Trickle Charge)
YesYes
Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Constant Current
Charge Mode
YesYes
YesYes Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Constant Voltage
Charge Mode
NoNo
No
No
Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Charger Timer
Control
Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Thermal Loop
Current Reduction
In C.C. Mode
ENCHR = Yes
Enable
OVP?
OVP Condition
Monitoring
VIN > 6.5V?
Shut Down
Mode
Shut Down
Mode
Shut Down
Mode
Disconnect Input
from charger
ENOVP = Yes
No
No
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
14 3783.2008.08.1.2
www.analogictech.com
Application Information
Programming the Over-Voltage
Protection Trip Point
The default over-voltage protection trip point of the
AAT3783 is set to 6.5V by the factory. However, the
over-voltage protection trip point can be programmed
from 3.8V to 7.5V by the user with one external resistor,
either R5 or R6. The placement of R5 is between IN and
OVP. The placement of R6 is between OVP and GND.
Table 2 summarizes resistor values for various over-
voltage protection trip points. Use 1% tolerance metal
film resistors for programming the desired OVP trip
point.
R6 (KΩ) R5 (KΩ) VOVP_TRIP POINT (V)
short open 7.5
0.499 open 7.25
1.3 open 7.0
3.01 open 6.75
open open 6.5
open 4.99 5.5
open 2.49 5.0
open 1.0 4.5
open short 3.87
Table 2: Programming OVP Trip Point for
AAT3783 with One Resistor.
Battery Connection
and Battery Voltage Sensing
Battery Connection (BAT)
A single cell Li-Ion/Polymer battery should be connected
between the BAT pin and ground.
Battery Voltage Sensing (BATS)
The BATS pin is provided to employ an accurate voltage
sensing capability to measure the positive terminal volt-
age at the battery cell being charged. This function
reduces measured battery cell voltage error between the
battery terminal and the charge control IC. The AAT3783
charge control circuit will base charging mode states
upon the voltage sensed at the BATS pin. The BATS pin
must be connected to the battery terminal for correct
operation. If the battery voltage sense function is not
needed, the BATS pin should be terminated directly to
the BAT pin. If there is concern of the battery sense
function inadvertently becoming an open circuit, the
BATS pin may be terminated to the BAT pin using a 10k
resistor. Under normal operation, the connection to the
battery terminal will be close to 0; if the BATS connec-
tion becomes an open circuit, the 10k resistor will pro-
vide feedback to the BATS pin from the BAT connection
with a voltage sensing accuracy loss of 1mV or less.
Constant Charge Current
The constant current mode charge level is user pro-
grammed with a set resistor placed between the ISET pin
and ground. The accuracy of the constant charge cur-
rent, as well as the preconditioning trickle charge cur-
rent, is dominated by the tolerance of the set resistor
used. For this reason, a 1% tolerance metal film resistor
is recommended for the set resistor function. The con-
stant charge current levels from 100mA to 1A may be set
by selecting the appropriate resistor value from Table 3.
Constant Charging
Current (mA) Set Resistor Value (kΩ)
10 162
20 80.6
50 32.4
100 16
200 8.06
300 5.36
400 4.02
500 3.24
600 2.67
700 2.26
800 2
900 1.78
1000 1.62
Table 3: RSET Values.
RSET (kΩ
Ω
)
Constant Charging Current (mA)
1
10
100
1000
10000
1 10 100 1000
Figure 2: Constant Charging Current
vs. Set Resistor Values.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 15
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Charge Termination Current
The charge termination current ICH_TERM can be pro-
grammed by connecting a resistor from TERM to GND:
ICH_TERM = · ICH_CC
15µA · RTERM
2V
Where:
ICH_TERM = Charge termination current level
ICH_CC = Programmed fast charge constant current level
RTERM = TERM resistor value
If the TERM pin is left open, the termination current will
set to 10% of the constant charging current as the
default value.
When the charge current drops to the defaulted 10% of
the programmed charge current level or programmed
terminated current in the constant voltage mode, the
device terminates charging and goes into a sleep state.
The charger will remain in this sleep state until the bat-
tery voltage decreases to a level below the battery
recharge voltage threshold (VRCH).
Consuming very low current in sleep state, the AAT3783
minimizes battery drain when it is not charging. This
feature is particularly useful in applications where the
input supply level may fall below the battery charge or
under-voltage lockout level. In such cases where the
AAT3783 input voltage drops, the device will enter sleep
state and automatically resume charging once the input
supply has recovered from the fault condition.
Protection Circuitry
Programmable Watchdog Timer
The AAT3783 contains a watchdog timing circuit to shut
down charging functions in the event of a defective bat-
tery cell not accepting a charge over a preset period of
time. Typically, a 0.1F ceramic capacitor is connected
between the CT pin and ground. When a 0.1F ceramic
capacitor is used, the device will time out a shutdown
condition if the trickle charge mode exceeds 25 minutes
and a combined trickle charge plus constant current
mode of 3 hours. When the device transitions to the
constant voltage mode, the timing counter is reset and
will time out after an additional 3 hours if the charge
current does not drop to the charge termination level.
Mode Time
Trickle Charge (TC) Time Out 25 minutes
Trickle Charge (TC) + Constant Current (CC)
Mode Time Out 3 hours
Constant Voltage (CV) Mode Time Out 3 hours
Table 4: Summary for a 0.1μF Ceramic Capacitor
Used for the Timing Capacitor.
The CT pin is driven by a constant current source and will
provide a linear response to increase in the timing
capacitor value. Thus, if the timing capacitor were to be
doubled from the nominal 0.1F value, the time-out
periods would be doubled. If the programmable watch-
dog timer function is not needed, it can be disabled by
terminating the CT pin to ground. The CT pin should not
be left floating or un-terminated, as this will cause errors
in the internal timing control circuit.
The constant current provided to charge the timing
capacitor is very small, and this pin is susceptible to
noise and changes in capacitance value. Therefore, the
timing capacitor should be physically located on the
printed circuit board layout as close as possible to the CT
pin. Since the accuracy of the internal timer is domi-
nated by the capacitance value, a 10% tolerance or bet-
ter ceramic capacitor is recommended. Ceramic capaci-
tor materials, such as X7R and X5R types, are a good
choice for this application.
Battery Over-Voltage Protection
An over-voltage event is defined as a condition where
the voltage on the BAT pin exceeds the maximum bat-
tery charge voltage and is set by the over-voltage pro-
tection threshold (VBOVP). If an over-voltage condition
occurs, the AAT3783 charge control will shut down the
device until the voltage on the BAT pin drops below VOVP
.
The AAT3783 will resume normal charging operation
after the over-voltage condition is removed.
Battery Temperature Monitoring
In the event of a battery over-temperature condition, the
charge control will turn off the internal pass device. After
the system recovers from a temperature fault, the device
will resume charging operation. The AAT3783 checks
battery temperature before starting the charge cycle, as
well as during all stages of charging. This is accomplished
by monitoring the voltage at the TS pin. This system is
intended for use with negative temperature coefficient
thermistors (NTC) which are typically integrated into the
battery package. Most of the commonly used NTC therm-
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
16 3783.2008.08.1.2
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istors in battery packs are approximately 10k at room
temperature (25°C). The TS pin has been specifically
designed to source 75A of current to the thermistor.
The voltage on the TS pin resulting from the resistive
load should stay within a window of 331mV to 2.39V. If
the battery becomes too hot during charging due to an
internal fault or excessive constant charge current, the
thermistor will heat up and reduce in value, pulling the
TS pin voltage lower than the TS1 threshold, and the
AAT3783 will stop charging until the condition is removed,
when charging will be resumed. If the use of the TS pin
function is not required by the system, it should be ter-
minated to ground using a 10k resistor. Alternatively,
on the AAT3783, the TS pin may be left open.
Over-Temperature Shutdown
The AAT3783 has a thermal protection control circuit
which will shut down charging functions should the inter-
nal die temperature exceed the preset thermal limit
threshold. Once the internal die temperature falls below
the thermal limit, normal operation will resume the pre-
vious charging state.
Digital Thermal Loop Control
Due to the integrated nature of the linear charging con-
trol pass device for the adapter mode, a special thermal
loop control system has been employed to maximize
charging current under all operation conditions. The
thermal management system measures the internal cir-
cuit die temperature and reduces the fast charge current
when the device exceeds a preset internal temperature
control threshold. Once the thermal loop control becomes
active, the fast charge current is initially reduced by a
factor of 0.44.
The initial thermal loop current can be estimated by the
following equation:
ITLOOP = ICH_CC · 0.44
The thermal loop control re-evaluates the circuit die tem-
perature every three seconds and adjusts the fast charge
current back up in small steps to the full fast charge cur-
rent level or until an equilibrium current is discovered
and maximized for the given ambient temperature condi-
tion. The thermal loop controls the system charge level;
therefore, the AAT3783 will always provide the highest
level of constant current in the fast charge mode possible
for any given ambient temperature condition.
Thermal Considerations
and High Output Current Applications
The AAT3783 is designed to deliver a continuous charg-
ing current. The limiting characteristic for maximum safe
operating charging current is its package power dissipa-
tion. Many considerations should be taken into account
when designing the printed circuit board layout, as well
as the placement of the IC package in proximity to other
heat generating devices in a given application design.
The ambient temperature around the IC will also have
an effect on the thermal limits of a battery charging
application.
The maximum limits that can be expected for a given
ambient condition can be estimated by the following
discussion. First, the maximum power dissipation for a
given situation should be calculated:
(T
J(MAX) -
T
A
)
P
D(MAX)
= θ
JA
Where:
PD(MAX) = Maximum Power Dissipation (W)
JA = Package Thermal Resistance (°C/W)
TJ = Thermal Loop Entering Threshold (°C) [115ºC]
TA = Ambient Temperature (°C)
Figure 3 shows the relationship of maximum power dis-
sipation and ambient temperature of AAT3783.
TA (°C)
PD(MAX) (W)
0
0.5
1
1.5
2
2.5
0 25 50 75 100
Figure 3: Maximum Power Dissipation Before
Entering Digital Thermal Loop.
Next, the power dissipation can be calculated by the fol-
lowing equation:
PD = [(VIN - VBAT) · ICH + (VIN · IOP)]
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 17
www.analogictech.com
Where:
PD = Total Power Dissipation by the Device
VIN = Input Voltage
VBAT = Battery Voltage as Seen at the BAT Pin
ICH = Constant Charge Current Programmed for the
Application
IOP = Quiescent Current Consumed by the Charger IC
for Normal Operation [0.4mA]
By substitution, we can derive the maximum charge cur-
rent before reaching the thermal limit condition (thermal
loop). The maximum charge current is the key factor
when designing battery charger applications.
(P
D(MAX) -
V
IN
·
I
OP
)
V
IN
- V
BAT
I
CH(MAX)
=
(T
J(MAX) -
T
A
)
θ
JA
I
CH(MAX)
=
-
V
IN
·
I
OP
V
IN
- V
BAT
In general, the worst condition is the greatest voltage
drop across the charger IC, when battery voltage is
charged up to the preconditioning voltage threshold and
before entering thermal loop regulation. Figure 4 shows
the maximum charge current in different ambient tem-
peratures.
VIN (V)
ICC_MAX (mA)
0
200
400
600
800
1000
4 4.5 5 5.5 6 6.5 7 7.5
TA = 25°C
TA = 45°C
TA = 85°C
TA = 60°C
Figure 4: Maximum Charging Current Before the
Digital Thermal Loop Becomes Active.
Input Capacitor
A 1F or larger capacitor is typically recommended for
CIN. CIN should be located as close to the device VIN pin
as practically possible. Ceramic, tantalum, or aluminum
electrolytic capacitors may be selected for CIN. There is
no specific capacitor equivalent series resistance (ESR)
requirement for CIN. However, for higher current opera-
tion, ceramic capacitors are recommended for CIN due to
their inherent capability over tantalum capacitors to
withstand input current surges from low impedance
sources such as batteries in portable devices.
Typically, 50V rated capacitors are required for most of
the application to prevent any surge voltage. Ceramic
capacitors selected as small as 1210 are available which
can meet these requirements. Other voltage rating
capacitor can also be used for the known input voltage
application.
Charger Input Capacitor
A 2.2F decoupling capacitor is recommended to be
placed between INCHR and GND.
Charger Output Capacitor
The AAT3783 only requires a 1F ceramic capacitor on
the BAT pin to maintain circuit stability. This value should
be increased to 10F or more if the battery connection is
made any distance from the charger output. If the
AAT3783 is used in applications where the battery can be
removed from the charger, such as with desktop charg-
ing cradles, an output capacitor greater than 10F may
be required to prevent the device from cycling on and off
when no battery is present.
Printed Circuit Board
Layout Recommendations
For proper thermal management and to take advantage
of the low RDS(ON) of the AAT3783, a few circuit board
layout rules should be followed: VIN and VOUT should be
routed using wider than normal traces, and GND should
be connected to a ground plane. To maximize package
thermal dissipation and power handling capacity of the
AAT3783 DFN34 package, solder the exposed paddle of
the IC onto the thermal landing of the PCB, where the
thermal landing is connected to the ground plane. This
AAT3783 has two exposed paddles (EP1 and EP2). EP1 is
connected to INCHR (pin 1) and EP2 is connected to GND
(pin 13). DO NOT make one whole thermal landing! If
heat is still an issue, multi-layer boards with dedicated
ground planes are recommended. Also, adding more
thermal vias on the thermal landing would help the heat
being transferred to the PCB effectively.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
18 3783.2008.08.1.2
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
18 3783.2008.08.1.2
www.analogictech.com
(op en)
R5
(op en)
R6
1μF
C1
Enable
JP1
+5V
6k
R7
Red LED
D1
2.2μF
C2
INCHR
EN_CHR
JP2 0.1μF
C4 13.3k
R2
1.62k
R1
INCHR
1.5k
R8
Red LED
D2
1.5k
R9
Green LED
D3
10k
R4
10μF
C3
INCHR
INCHR
JP3
(open)
R3
1
2
3
BAT
GND
TS
1
2
VIN
GND
4V - 7.5V
C1 1206 X7R 1μF 50V GRM31MR71H105KA88
(C1 1206 X7R 2.2μF 50V GRM31CR71H225KA88L)
(C1 1210 X7R 4.7μF 50V GRM32ER71H475KA88L)
C2 0805 X5R 2.2μF 10V GRM188R61A225KE34
C3 0805 X7R 10μF 10V GRM21BR71A106KE51L
ENOVP
5
IN
16
GND
13
TS 4
STAT 8
IN
15
ENCHR
11
FLT
7
BATS 2
BAT 3
OVP
6
ISET 14
TERM 12
ADPP 9
INCHR
1
CT 10
AAT3783
U1
Figure 5: AAT3783 Evaluation Board Schematic.
Component Part# Description Manufacturer
U1 AAT3783IRN
1A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage
Protection; TDFN Package
AnalogicTech
R1 Chip Resistor 1.62K, 1%, 1/4W; 0603 Vishay
R2 Chip Resistor 13.3K, 1%, 1/4W; 0603 Vishay
R4 Chip Resistor 10K, 5%, 1/4W; 0603 Vishay
R7 Chip Resistor 6K, 5%, 1/4W; 0603 Vishay
R8, R9 Chip Resistor 1.5K, 5%, 1/4W; 0603 Vishay
C1 GRM31MR71H105KA88 CER 1F 50V 10% X7R 1206 Murata
C2 GRM188R61A225KE34 CER 2.2F 10V 10% X5R 0805 Murata
C3 GRM21BR71A106KE51L CER 10F 10V 10% X7R 0805 Murata
C4 GRM188R71E104KA01 CER 0.1F 25V 10% X7R 0603 Murata
JP1, JP2, JP3 PRPN401PAEN Conn. Header, 2mm zip Sullins Electronics
D1, D2 CMD15-21SRC/TR8 Red LED; 1206 Chicago Miniature Lamp
D3 CMD15-21VGC/TR8 Green LED; 1206 Chicago Miniature Lamp
Table 5: AAT3783 Evaluation Board Bill of Materials.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 19
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
3783.2008.08.1.2 19
www.analogictech.com
Figure 5: AAT3783 Evaluation Board Figure 6: AAT3783 Evaluation Board
Top Layer. Middle Layer.
Figure 7: AAT3783 Evaluation Board Figure 8: Magnified View of Exposed Paddles
Bottom Layer. on AAT3783 Evaluation Board Top Layer.
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
20 3783.2008.08.1.2
www.analogictech.com
AAT3783
1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage ProtectionBatteryManagerTM
PRODUCT DATASHEET
20 3783.2008.08.1.2
www.analogictech.com
Advanced Analogic Technologies, Inc.
3230 Scott Boulevard, Santa Clara, CA 95054
Phone (408) 737-4600
Fax (408) 737-4611
© Advanced Analogic Technologies, Inc.
AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual
property rights are implied. AnalogicTech reserves the right to make changes to their products or specifi cations or to discontinue any product or service without notice. Except as provided in AnalogicTech’s terms and
conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties
relating to fi tness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate
design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to
support this warranty. Specifi c testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other
brand and product names appearing in this document are registered trademarks or trademarks of their respective holders.
Ordering Information
Package Marking1Part Number (Tape and Reel)2
TDFN34-16 XQXYY AAT3783IRN-4.2-T1
All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor
products that are in compliance with current RoHS standards, including the requirement that lead not exceed
0.1% by weight in homogeneous materials. For more information, please visit our website at
http://www.analogictech.com/about/quality.aspx.
Package Information
TDFN34-16
Top View Bottom View
Side View
3.000
±
0.050
4.000
±
0.050
Index Area
R0.15 (REF)
Pin 1 ID
1.600
±
0.050
1.600
±
0.050
0.430
±
0.050
0.25 REF
0.35 REF
2.350
±
0.050 0.700
±
0.050
0 + 0.100
-0.000 0.230
±
0.050
0.750
±
0.050
0.230
±
0.050
0.450
±
0.050
All dimensions in millimeters.
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in BOLD.
3. The leadless package family, which includes QFN, TQFN, DFN, TDFN and STDFN, has exposed copper (unplated) at the end of the lead terminals due to the manufacturing
process. A solder fillet at the exposed copper edge cannot be guaranteed and is not required to ensure a proper bottom solder connection.
