201889B.pdf

DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
General Description
Features
The AAT3686 BatteryManager is a highly integrated single-cell lithium-ion/polymer battery charger IC designed
to operate with USB port and AC adapter inputs. It
requires the minimum number of external components.
• USB Port/AC Adapter System Power Charger
▪ USB: Programmable to 500mA for USB Hi/Lo
▪ Adapter: Programmable to 1.5A Max
• 4.0V to 5.5V Input Voltage Range
• Adapter Present Indicator (ADPP# Pin)
• Adapter Presence Automatically Disables USB Charging
• High Level of Integration With Internal:
▪ Charging Devices
▪ Reverse Blocking Diodes
▪ Current Sensing
• Automatic Recharge Sequencing
• Digital Thermal Regulation in ADP Charge
• Charge Reduction Loop in USB Charge
• Battery Temperature Monitoring
• Full Battery Charge Auto Turn-Off
• Over-Voltage and Emergency Thermal Protection
• Power On Reset and Soft Start
• Serial Interface Status Reporting
• TDFN34-16 or TDFN44-16 Package
The AAT3686 precisely regulates battery charge voltage
and current for 4.2V lithium-ion/polymer battery cells.
Adapter charge current rates can be programmed up to
1.5A. In the absence of an adapter and with a USB port
connected, the battery can also be charged by USB power.
Depending on the USB port type, the AAT3686 charge
current can be programmed for two separate levels up to
500mA. An optional Charge Reduction Loop is also built in
to allow users to charge the battery with available current
from a USB port, while keeping the port voltage regulated. USB charging is disabled when an adapter is present.
Battery temperature and charge state are fully monitored for fault conditions. In the event of an over-voltage or over-temperature failure, the device will automatically shut down, thus protecting the charging device,
control system, and the battery under charge. Status
monitor output pins are provided to indicate the battery
charge status by directly driving two external LEDs. A
serial interface output is available to report 22 various
status states to a microcontroller.
Applications
•
•
•
•
•
•
The AAT3686 is available in a Pb-free, thermallyenhanced, space-saving TDFN34-16 (3 × 4mm) or
TDFN44-16 (4 × 4mm) package and is rated over the
-40°C to +85°C temperature range.
Cellular Telephones
Digital Still Cameras
Hand-Held PCs
MP3 Players
Personal Data Assistants (PDAs)
Other Lithium-Ion/Polymer Battery-Powered Devices
Typical Application
Enable
USB Input
EN
USB
CHR
USBSEL
USB Hi/Lo Select
BATT+
USBH
RSETH
BAT
USBL
C2
10µF
TS
AAT3686
RSETL
CT
CT
ADP Present
ADPP#
ADP Input
BATT-
GND
ADP
ADPSET
RSET
STAT1
DATA
TEMP
STAT2
Battery Pack
Serial Data
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
1
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Pin Descriptions
Pin #
(TDFN34-16/
TDFN44-16)
Name
Type
1
2
3
4
USB
BAT
ADP
GND
In
In/Out
In
Ground
5
CHR
In/Out
6
7
8
9
10
11
EN
ADPP#
TS
DATA
STAT2
STAT1
In
Out
In/Out
Out
Function
USB power supply input.
Battery charging and sensing.
Adapter input.
Ground connection.
Resistor divider to set USB voltage regulation for charge reduction mode. Leave
this pin open for default 4.5V USB regulation point. Tie to USB pin to disable this
function.
Enable pin. Logic high enables the IC.
Adapter present indicator. This pin is open drain until ADP pin reaches threshold
Connect to 10kΩ NTC thermistor.
Status report to microcontroller via serial interface, open-drain.
Battery charge status indicator pin to drive an LED: active low, open-drain.
12
CT
In/Out
13
14
15
16
EP
USBSEL
USBL
USBH
ADPSET
In
In/Out
Timing capacitor to adjust internal watchdog timer. Set maximum charge time for
adapter powered trickle, CC, and CV charge modes. The watchdog timer only sets
the timers for adapter battery charging; there is no timeout for the battery charging from the USB input. If timing function is not needed, terminate this pin to
ground.
When USB is present, use this pin to toggle between 100mA and 500mA limit.
Connect resistor here to set charge current for low-current USB port.
Connect resistor here to set charge current for high-current USB port.
Use resistor at this pin to set adapter charging current.
Exposed paddle (bottom); connect to GND directly beneath package.
Pin Configuration
TDFN34-16
(Top View)
2
TDFN44-16
(Top View)
USB
1
16
ADPSET
USB
1
16
ADPSET
BAT
2
15
USBH
BAT
2
15
USBH
ADP
3
14
USBL
14
USBL
GND
4
13
USBSEL
ADP
GND
3
4
13
USBSEL
CHR
5
12
5
12
CT
EN
6
11
CT
STAT1
CHR
EN
6
11
STAT1
ADPP#
7
10
STAT2
ADPP#
7
10
STAT2
TS
8
9
DATA
TS
8
9
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
AAT3686 Feature Options
Product
Internal Pull-Up
Resistor on EN Pin
Can Leave
TS Pin Open
Battery Recharge
Voltage Active
AAT3686
No
No
Always active
Absolute Maximum Ratings1
Symbol
VP
VN
TJ
TLEAD
Description
USB, ADP Input Voltage, <30ms, Duty Cycle <10%
USB, ADP Input Voltage, Continuous
BAT, USBSEL, USBH, USBL, ADPSET, STAT1, STAT2, ADPP#, DATA, TS, CT, CHR, EN
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads)
Value
-0.3 to 7.0
-0.3 to 6.0
-0.3 to VP + 0.3
-40 to 150
300
Units
V
°C
Thermal Information2
Symbol
JA
PD
Description
Maximum Thermal Resistance
Maximum Power Dissipation
Value
Units
37
2.7
°C/W
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.
2. Mounted on an FR4 board.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
3
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Electrical Characteristics1
VADP = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C.
Symbol
Description
Conditions
Operation
USB, ADP USB Port or Adapter Voltage Range
VADPP
Adapter Present Indicator Threshold Voltage
ADP Voltage Level to Disable USB Charging
Under-Voltage Lockout
VUVLO
Under-Voltage Lockout Hysteresis
Operating Current
IOP
ISLEEP
Sleep Mode Current
Reverse Leakage Current from BAT Pin
ILeakage
Voltage Regulation
VBAT_EOC1
End of Charge Voltage Accuracy
VBAT/VBAT EOC Voltage Tolerance
VMIN
Preconditioning Voltage Threshold
Min
Typ
4.0
USB Present
4.25
Max
Units
5.5
4.5
4.7
V
VU_DSBL
VRCH
Rising Edge
3.0
150
0.75
0.3
1.0
CC Charge Current = 500mA
VBAT = 4.25V
VBAT = 4V, USB, ADP Pins Open
4.158
2.8
4.2
0.5
3.0
4.3
1.9
VBAT_EOC 0.1
4.5
2.0
Battery Recharge Voltage Threshold
VUSB_CHR
USB Charge Reduction Regulation
VCHR
CHR Pin Voltage Accuracy
Current Regulation
Charge Current
ICH
ICH/ICH
Charge Current Regulation Tolerance
VADPSET
ADPSET Pin Voltage
VUSBH
USBH Pin Voltage
VUSBL
USBL Pin Voltage
KIA
Current Set Factor: ICHARGE/IADPSET
KIUH
Current Set Factor: ICHARGE/IUSBH
Current Set Factor: ICHARGE/IUSBL
KIUL
Charging Devices
RDS(ON)A
Adapter Charging Transistor On Resistance
USB Charging Transistor On Resistance
RDS(ON)U
No Connection on CHR Pin
100
CC Mode
1.5
1.0
4.242
mV
mA
μA
V
%
3.15
V
4.64
2.1
10
1500
mA
%
2.0
V
4000
2000
VIN = 5.5V
0.2
0.4
0.25
0.5
0.35
0.65
Ω
1. The AAT3686 output charge voltage is specified over the 0° to 70°C ambient temperature range; operation over the -40°C to +85°C temperature range is guaranteed by design.
4
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Electrical Characteristics1
VADP = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C.
Symbol
Description
Logic Control / Protection
Input High Threshold
VUSBSEL(H)
VUSBSEL(L)
Input Low Threshold
VEN(H)
Input High Threshold
VEN(L)
Input Low Threshold
VADPP#
Output Low Voltage
Preconditioning Time Out (ADP mode only)
TP
Preconditioning and Constant Current Mode
TC
Time Out (ADP mode only)
Constant Voltage Mode Time Out (ADP
TV
mode only)
VSTAT
Output Low Voltage
ISTAT
STAT Pin Current Sink Capability
VOVP
Over-Voltage Protection Threshold
ITK/ICHG
ITERM/ICHG
ITS
Pre-Charge Current
Charge Termination Threshold Current
TS Hot Temperature Fault
TS2
TS Cold Temperature Fault
DATA Pin Sink Current
ADPP# Current Sink Capability
Input High Threshold
Input Low Threshold
Status Request Pulse Width
System Clock Period
Data Output Frequency
Thermal Loop Regulation
Thermal Loop Entering Threshold
Thermal Loop Exiting Threshold
Over-Temperature Shutdown Threshold
Min
Typ
Max
Units
1.6
0.4
V
1.6
0.4
ADPP# Pin Sinks 4mA
CCT = 100nF, V_ADP = 5.5V
25
Minute
3.0
Hour
STAT Pin Sinks 4mA
For
For
For
For
0.4
Adapter or USBH Mode
USBL Mode
Adapter or USBH Mode
USBL Mode
Current Source from TS Pin
TS1
I_DATA
I_ADPP#
VDATA(H)
VDATA)(L)
SQPULSE
tPERIOD
fDATA
TREG
TLOOP_IN
TLOOP_OUT
TOVSD
Conditions
Threshold
Hysteresis
Threshold
Hysteresis
DATA Pin is Active Low State
ADPP# Pin is Active Low State
70
310
2.2
8.0
4.4
10
50
7.5
35
80
330
15
2.3
10
%
90
350
2.4
3
μA
mV
V
mV
mA
8
1.6
0.4
Status Request
V
mA
V
200
50
20
90
110
85
145
V
ns
μs
kHz
°C
1. The AAT3686 output charge voltage is specified over the 0° to 70°C ambient temperature range; operation over the -40°C to +85°C temperature range is guaranteed by design.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
5
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Typical Characteristics
IFASTCHARGE vs. RSET
Battery Voltage vs. Supply Voltage
4.242
4.221
1000
ADP
VBAT (V)
IFASTCHARGE (mA)
10000
USBL
100
USBH
4.200
ADP
4.179
4.158
4.5
10
1
USBH
10
100
4.75
RSET (kΩ)
5.0
5.25
5.5
Supply Voltage (V)
Recharge Voltage vs. Temperature
End of Charge Voltage vs. Temperature
4.242
4.140
4.130
4.120
4.221
ADP
4.100
4.090
VBAT (V)
VRCH (V)
4.110
USBH
4.080
4.070
ADP
4.200
USBH
4.179
4.060
4.050
4.040
-50
-25
0
25
50
75
4.158
-50
100
-25
0
Temperature (°°C)
25
50
75
100
Temperature (°°C)
Preconditioning Threshold
Voltage vs. Temperature
Preconditioning Charge Current vs. Temperature
(ADPSET = 8.06kΩ
Ω; USBH = 8.06kΩ)
120
3.05
60
3.04
VMIN (V)
USBH
3.01
3.00
2.99
ADP
2.98
2.97
110
55
ADP
100
50
USBH
90
45
2.96
2.95
-50
-25
0
25
50
Temperature (°°C)
6
75
100
80
-50
-25
0
25
50
75
Temperature (°C)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
40
100
ICH USB (mA)
3.02
ICH ADP (mA)
3.03
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Typical Characteristics
Fast Charge Current vs. Temperature
Charging Current vs. Battery Voltage
(ADPSET = 8.06kΩ
Ω; USBH = 8.06kΩ)
1100
540
1080
530
500
1000
490
980
480
ADP
470
940
460
920
450
900
-50
-25
0
25
50
75
0.8
ICH (A)
510
1020
960
1.0
520
USBH
1040
ICH USB (mA)
ICH ADP (mA)
1060
(Adapter; ADPSET = 8.06kΩ
Ω)
1.2
0.6
0.4
0.2
0.0
440
100
2.5
2.9
3.3
Temperature (°C)
120
500
100
400
80
ICH (mA)
ICH (mA)
(USBL; USBL = 40.2kΩ
Ω)
600
300
200
60
40
20
100
0
3.0
3.5
4.0
4.5
2.5
3.0
Battery Voltage (V)
600
VBAT = 3.3V
VBAT = 3.9V
VBAT = 3.5V
200
4.0
VBAT = 3.3V
500
400
0
4.5
(USBH; USBH = 8.06kΩ
Ω)
ICH (mA)
ICH (mA)
600
4.0
Fast Charge Current vs. Supply Voltage
(Adapter; ADPSET = 8.06kΩ
Ω)
800
3.5
Battery Voltage (V)
Fast Charge Current vs. Supply Voltage
1000
4.5
Charging Current vs. Battery Voltage
(USBH; USBH = 8.06kΩ
Ω)
1200
4.1
Battery Voltage (V)
Charging Current vs. Battery Voltage
0
2.5
3.7
400
VBAT = 3.5V
VBAT = 3.9V
300
200
100
4.5
5.0
Supply Voltage (V)
5.5
6.0
0
4.0
4.25
4.5
4.75
5.0
5.25
5.5
5.75
6.0
Supply Voltage (V)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
7
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Typical Characteristics
Fast Charge Current vs. Supply Voltage
Fast Charge Current vs. Supply Voltage
(USBL; USBL = 40.2kΩ
Ω)
120
(USBH; USBH = 8.06kΩ
Ω)
600
VBAT = 3.5V
VBAT = 3.3V
80
VBAT = 3.9V
60
40
20
0
0°C
500
ICH (mA)
ICH (mA)
100
25°C
300
200
100
4.0
4.5
5.0
5.5
6.0
0
4.4
6.5
4.5
4.6
Supply Voltage (V)
1.4
1.3
1.3
-40°C
VIH (V)
VIH (V)
1.1
0.9
0.8
0.8
+85°C
0.5
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
0.4
6.0
4.2
4.4
4.6
Supply Voltage (V)
5.4
5.6
VIL vs. Supply Voltage
USBSEL (Falling)
1.4
1.3
-40°C
-40°C
1.1
1.0
0.9
0.8
6.0
5.8
6.0
+25°C
1.0
0.9
0.8
0.7
+85°C
0.6
5.8
1.2
+25°C
VIH (V)
VIH (V)
5.2
USBSEL (Rising)
0.7
+85°C
0.6
0.5
0.5
4.2
4.4
4.6
4.8
5.0
5.2
5.4
Supply Voltage (V)
8
5.0
VIH vs. Supply Voltage
1.3
1.1
4.8
Supply Voltage (V)
1.4
1.2
+25°C
0.9
0.6
0.5
0.4
-40°C
1.0
0.7
+85°C
0.6
5.0
1.2
+25°C
1.0
0.7
4.9
EN Pin (Falling)
1.4
1.1
4.8
VIL vs. Supply Voltage
EN Pin (Rising)
1.2
4.7
Supply Voltage (V)
VIH vs. Supply Voltage
0.4
70°C
400
5.4
5.8
6.0
0.4
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
Supply Voltage (V)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Typical Characteristics
Adapter Mode Supply Current
vs. ADPSET Resistor
USB Charge Current vs. Time
(USBH; USBH = 8.06kΩ
Ω)
0.80
USB VBUS
(200mV/div)
0.70
USB Charge
Current
(200mA/div)
IQ (mA)
0.60
Constant Current
0.50
Charge Reduction
Mode Activated
0.40
0.30
USB Peripheral
Current
Consumption
(200mA/div)
Pre-Conditioning
0.20
0.10
0.00
1
10
100
0
1000
2
4
ADPSET Resistor (kΩ
Ω)
6
8
10
Time (sec)
Counter Timeout vs. Temperature
CT Pin Capacitance vs. Counter Timeout
10
2.0
8
1.8
6
1.6
Capacitance (μ
μF)
Counter Timeout (%)
(CT = 0.1µF)
4
2
0
-2
-4
-6
-8
-10
Precondition Timeout
1.4
1.2
1.0
0.8
Precondition + Constant Current Timeout
or Constant Voltage Timeout
0.6
0.4
0.2
-50
-25
0
25
50
75
100
Temperature (°°C)
0.0
0
2
4
6
8
10
Time (hours)
Temperature Sense Output Current
vs. Temperature
TS Pin Current (μA)
88
86
84
82
80
78
76
74
72
-50
-25
0
25
50
75
100
Temperature (°°C)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
9
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Functional Block Diagram
Reverse Blocking
USB
USBSEL
USBH
USBL
CHR
Current
Compare
Charge
Reduction
Loop
CV/
Precharge
Charge
Control
Constant
Current
ADP
STAT1
STAT2
DATA
BAT
OverTemperature
Protect
Current
Compare
ADPSET
ADPP#
UVLO
Reverse Blocking
Voltage
Sense
80μA
TS
Charge
Status
Serial
Data
Window
Comparator
IC enable
Watchdog
Timer
CT
EN
GND
Functional Description
greater than 4.4V is present.
The AAT3686 is a highly integrated single-cell lithiumion/polymer battery charger IC designed to operate with
USB port and AC adapter inputs, while requiring a minimum number of external components. The AAT3686
precisely regulates battery charge voltage and current
for 4.2V lithium-ion/polymer battery cells.
Status monitor output pins are provided to indicate the
battery charge status by directly driving two external
LEDs. A serial interface output is available to report 22
various status states to a microcontroller.
The adapter charge input constant current level can be
programmed up to 1.5A for rapid charging applications.
In the absence of a high current adapter input source,
the AAT3686 can be powered from a USB port VBUS supply. Depending on the USB port type, the AAT3686 constant charge current can be externally programmed for
two levels, USB high and USB low, for maximum constant current charge levels up to 500mA. Typically, the
USB charge levels are set at 500mA and 100mA for the
USBH and USBL modes; however, the user may program
either mode to any level up to 500mA.
The USBH/L mode has automatic Charge Reduction Loop
control to allow users to charge the battery with limited
available current from a USB port, while maintaining the
regulated port voltage. This system assures the battery
charge function will not overload a USB port while charging if other system demands also share power with the
respective port supply. The USB charge function is automatically disabled when an adapter input power source
10
Battery temperature and charge state are fully monitored for fault conditions. In the event of an over-voltage
or over-temperature failure, the device will automatically shut down, thus protecting the charging device,
control system, and the battery under charge. In addition to internal charge controller thermal protection, the
AAT3686 also provides a temperature sense feedback
function (TS pin) from the battery to shut down the
device in the event the battery exceeds its own thermal
limit during charging. All fault events are reported to the
user either by the simple status LEDs or via the DATA pin
function.
Charging Operation
Regardless of which charge input function is selected
(i.e., either the adapter input or USB input), the AAT3686
has four basic modes for the battery charge cycle: preconditioning/trickle charge; constant current/fast charge;
constant voltage; and end of charge (see Figure 1).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Charge Complete Voltage
Preconditioning
Trickle Charge
Phase
Constant Current
Charge Phase
Constant Voltage
Charge Phase
I = Max CC
Regulated Current
Constant Current Mode
Voltage Threshold
Trickle Charge and
Termination Threshold
I = CC / 10
Figure 1: Current vs. Voltage Profile During Charging Phases.
Battery Preconditioning
Constant Voltage Charging
Before the start of charging, the AAT3686 checks several conditions in order to assure a safe charging environment. The input supply must be above the minimum
operating voltage, or under-voltage lockout threshold
(VUVLO), for the charging sequence to begin. Also, the cell
temperature, as reported by a thermistor connected to
the TS pin from the battery, must be within the proper
window for safe charging. When these conditions have
been met and a battery is connected to the BAT pin, the
AAT3686 checks the state of the battery. If the cell voltage is below the preconditioning voltage threshold
(VMIN), the AAT3686 begins preconditioning the cell.
The system transitions to a constant voltage charging
mode when the battery voltage reaches the output
charge regulation threshold (VBAT) during the constant
current fast charge phase. The regulation voltage level
is factory programmed to 4.2V (±1%). Charge current
in the constant voltage mode drops as the battery cell
under charge reaches its maximum capacity.
The battery preconditioning trickle charge current is
equal to the fast charge constant current divided by 10
(USBL divided by 2). For example, if the programmed
fast charge current is 500mA, then the preconditioning
mode (trickle charge) current will be 50mA. Cell preconditioning is a safety precaution for a deeply discharged
battery and also aids in limiting power dissipation in the
pass transistor when the voltage across the device is at
the greatest potential.
Fast Charge / Constant Current Charging
Cell preconditioning continues until the voltage on the
BAT pin exceeds the preconditioning voltage threshold
(VMIN). At this point, the AAT3686 begins the constant
current fast charging phase. The fast charge constant
current (ICC) amplitude is determined by the charge
mode, ADP, USBH or USBL, and is programmed by the
user via the RSET, RSETH, and RSETL resistors. The AAT3686
remains in constant current charge mode until the battery reaches the voltage regulation point, VBAT.
End of Charge Cycle Termination
and Recharge Sequence
When the charge current drops to 7.5% (35% for USBL)
of the programmed fast charge current level in the constant voltage mode, the device terminates charging and
goes into a standby state. The charger will remain in a
standby state until the battery voltage decreases to a
level below the battery recharge voltage threshold
(VRCH).
When the input supply is disconnected or drops below
UVLO or EN = 0, the charger will automatically enter
power-saving sleep mode. Consuming an ultra-low
0.3μA in sleep mode, the AAT3686 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 AAT3686 input voltage
drops, the device will enter sleep mode and automatically resume charging once the input supply has recovered from its fault condition.
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11
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
System Operation Flow Chart
Output
Output
ADPP
ADPP
Yes
ADP
Voltage
Test
ADP > VADPP
ADP
Power Select
Yes
UVLO
VP > VUVLO
Yes
Switch
Switch
On
On
No
No
USB
ADP
ADP
Loop
Loop
Power
PowerOn
On
Reset
Reset
Sleep
Sleep
Mode
Mode
Enable
No
USB
USBLow
Low
Current
CurrentLoop
Loop
USB Detect
USBSEL > 0
Thermal
Thermal
Loop
Loop
Enable
Enable
Yes
USB
USBHigh
High
Current
CurrentLoop
Loop
Fault
Conditions Monitor
No
No
Timing
Device Temp. Monitor
Yes
TJ > 110°C
OV, OT
No
Shutdown
Shut Down
Mode
Mode
No
Recharge Test
VRCH > VBAT
Yes
Battery
Temp. Monitor
VTS1 <TS<VTS2
No
Thermal
ThermalLoop
Loop
Current
Current
Reduction
Reductionin
inADP
ADP
Charging
ChargingMode
Mode
Battery
Battery
Temp.
Temp.Fault
Fault
Charge
Charge
Safety
Safety
Timer
Timer
Yes
Preconditioning Test
VMIN > VBAT
Yes
Expire
Yes
Low
LowCurrent
Current
Conditioning
Conditioning
Charge
Charge
Yes
Current
Current
Charging
Charging
Mode
Mode
Yes
Voltage
Voltage
Charging
Charging
Mode
Mode
Set
No
Current Phase Test
VCH > VBAT
No
Voltage Phase Test
IBAT > IMIN
Yes
No
Charge
Charge
Completed
Completed
12
USB
USBLoop
Loop
Current
Current
Reduction
Reductionin
inUSB
USB
Charging
ChargingMode
Mode
USB
USBVoltage
Voltage
Regulation
Regulation
Enable
Enable
No
USB Voltage Test
VUSB < 4.5V
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DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Application Information
AC Adapter / USB System
Power Charging
Adapter Mode
In the adapter mode, constant current charge levels up
to 1.5A can be programmed by the user. The AAT3686
system control will always select the adapter input over
the USB supply input whenever adapter voltage is present on the ADP pin. The AAT3686 will operate from the
adapter input over a 4.0V to 5.5V range.
The constant current fast charge current for the adapter
input mode is set by the RSET resistor connected between
the ADPSET and ground. Refer to Table 1 for recommended RSET values for a desired constant current
charge level. The presence of voltage on the adapter
input is indicated by the ADPP# pin function. This indicator pin is an open drain and will pull the ADPP# pin low
when voltage is detected on the ADP pin. The precise
charging function in the adapter mode may be read from
the DATA pin and/or status LEDs. Please refer to the
Battery Charge Status Indication discussion in this datasheet for further details on data reporting.
Thermal Loop Control
Due to the integrated nature of the linear charging control 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 circuit 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 = ICC · 0.44
The thermal loop control re-evaluates the circuit die temperature every three seconds and adjusts the fast charge
current back up in small steps to the full fast charge current level or until an equilibrium current is discovered
and maximized for the given ambient temperature condition. The thermal loop controls the system charge level;
therefore, the AAT3686 will always provide the highest
level of constant current in the fast charge mode possible
for any given ambient temperature condition.
Adapter Input Charge Inhibit and Resume
The AAT3686 has an under-voltage lockout and power
on reset feature so that the charger will suspend charging and shut down if the input supply to the adapter pin
drops below the UVLO threshold. When power is reapplied to the adapter pin or the UVLO condition recovers and ADP > VBAT, the system charge control will assess
the state of charge on the battery cell and will automatically resume charging in the appropriate mode for
the condition of the battery.
USB Mode
The AAT3686 provides an input for intelligent USB
charging. When no voltage is present on the adapter
input pin, the charge controller will automatically switch
to accepting power from the USB input. The USB charge
mode provides two programmable fast charge levels up
to 500mA each, USB high and USB low, USBH and USBL,
respectively. The USBH or USBL modes may be externally selected by the USB select pin (USBSEL). USBSEL
is internally pulled low through a 1M resistor. When
the USBSEL pin is connected to a logic high level, the
USBH level will be active. Conversely, when USBSEL is
pulled to a logic low level (ground), the USBL level will
be used for charging. Typically, USBH is set for 500mA
and USBL is set for 100mA. However, these two USB
charge levels may be user programmed to any level
between 50mA and 500mA by selecting the appropriate
resistor values for RSETH and RSETL. Refer to Table 1 for
recommended RSETH and RSETL values for the desired USB
input constant current charge levels.
USB Charge Reduction
In many instances, product system designers do not
know the real properties of a potential USB port used to
supply power to the battery charger. Typically, powered
USB ports found on desktop and notebook PCs should
supply up to 500mA. In the event a USB port being used
to supply the charger is unable to provide the programmed fast charge current or if the system under
charge must also share supply current with other functions, the AAT3686 will automatically reduce USB fast
charge current to maintain port integrity and protect the
host system.
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13
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
ICC
ADP
RSET (k)
50
75
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
USBH
RSET (k)
USBL
RSET (k)
86.6
57.6
42.2
21.0
13.7
10.2
8.06
6.65
5.62
4.87
4.32
3.83
3.48
3.16
2.87
2.67
2.43
86.6
57.6
42.2
20.5
13.7
10.2
8.06
6.65
5.62
4.87
4.32
3.83
3.48
3.16
2.87
2.67
2.43
N/A
84.5
43.2
28.0
21.0
16.9
13.3
11.5
10.2
9.09
8.06
7.32
6.65
6.04
5.62
5.36
Table 1: Resistor Values.
USB
VUSB
R11
1.025M
CHR
R12
VCHR = 2.0V
825k
directly to the USB input pin (see Figure 2).
The following equation can be used to approximate a
USB charge reduction threshold below 4.5V:
VUSBCHR =
2.0V
R12
R12 + R11
Where R11/R12 << 1M.
USB Input Charge Inhibit and Resume
The AAT3686 UVLO and power on reset feature will function when the USB input pin voltage level drops below
the UVLO threshold. At this point, the charger will suspend charging and shut down. When power is re-applied
to the USB pin or the UVLO condition recovers, the system charge control will assess the state of charge on the
battery cell and will automatically resume charging in
the appropriate mode for the condition of the battery.
Enable / Disable
The AAT3686 provides an enable function to control the
charger IC on and off. The enable (EN) pin is active high.
When pulled to a logic low level, the AAT3686 will be
shut down and forced into the sleep state. Charging will
be halted regardless of the battery voltage or charging
state. When the device is re-enabled, the charge control
circuit will automatically reset and resume charging
functions with the appropriate charging mode based on
the battery charge state and measured cell voltage.
Programming Charge Current
Figure 2: Internal Equivalent Circuit
for the CHR Pin.
The USB charge reduction system becomes active when
the voltage on the USB input falls below the USB charge
reduction threshold (VUSBCHR), which is typically 4.5V.
Regardless of which USB charge function is selected
(USBH or USBL), the charge reduction system will
reduce the fast charge current level in a linear fashion
until the voltage sensed on the USB input recovers above
the charge reduction threshold voltage. The USB charge
reduction threshold (VUSBCHR) can be externally set to a
value lower than 4.5V by placing a resistor divider network between VUSB and ground with the center connected
to the CHR pin. The USB charge reduction feature can be
disabled by connecting a 10k resistor from the CHR pin
14
The fast charge constant current charge level for both
adapter and USB input modes are programmed with set
resistors placed between the ADPSET, USBH, and USBL
pins and ground. The accuracy of the fast charge, as well
as the preconditioning trickle charge current, is dominated by the tolerance of the set resistor used. For this
reason, 1% tolerance metal film resistors are recommended for the set resistor function.
Fast charge constant current levels from 50mA to 1.5A
can be set by selecting the appropriate resistor value
from Table 1. The RSET resistor should be connected
between the ADPSET pin and ground.
The USB input fast charge constant current charge control
provides for two current set levels, USBH and USBL. The
USBSEL pin is used to select the high or low charge current levels in the USB charge mode. When the USBSEL pin
is pulled to a voltage level above the VUSBSEL(H) threshold,
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DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
the USBH current level will be selected. Conversely, this
pin should be pulled below VUSBSEL(L) to enable the USBL
charge level. Typically, the two RSETH and RSETL resistors for
the USBH and USBL functions are fixed for 500mA and
100mA USB fast charge levels. However, these two
charge levels can be set to any level between 50mA and
500mA depending upon the system design requirements
for a given USB charge application. Refer to Table 1 and
Figure 3 for recommended RSETH and RSETL values.
IFASTCHARGE (mA)
10000
1000
USBL
100
10
1
ADPSET
USBH
10
100
1000
RSET (kΩ
Ω)
The CT pin is driven by a constant current source and
will provide a linear response to increases in the timing
capacitor value. Thus, if the timing capacitor were to be
doubled from the nominal 0.1μF value, the time-out
times would be doubled.
If the programmable watchdog timer function is not
needed, it can be disabled by connecting the CT pin to
ground. The CT pin should not be left floating or unterminated, 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 closely as possible to the
CT pin. Since the accuracy of the internal timer is dominated by the capacitance value, 10% tolerance or better
ceramic capacitors are recommended. Ceramic capacitor
materials, such as X7R and X5R type, are a good choice
for this application.
Over-Voltage Protection
Figure 3: IFASTCHARGE vs. RSET.
Protection Circuitry
Programmable Watchdog Timer
The AAT3686 contains a watchdog timing circuit for the
adapter input charging mode. No watchdog timing functions are active for the USB input mode. Typically, a
0.1μF ceramic capacitor is connected between the CT pin
and ground. When a 0.1μF ceramic capacitor is used, the
device will time a shutdown condition if the trickle
charge mode exceeds 25 minutes and a combined trickle charge plus fast charge mode of three hours. When
the device transitions to the constant voltage mode, the
timing counter is reset and will time out after three
hours and shut down the charger (see Table 2).
Mode
Time
Trickle Charge Time Out
Trickle Charge + Fast Charge (CC) Time Out
Constant Voltage (VC) Mode Time Out
25 minutes
3 hours
Table 2: Summary for a 0.1μF Used
for the Timing Capacitor.
An over-voltage event is defined as a condition where
the voltage on the BAT pin exceeds the maximum battery charge voltage and is set by the over-voltage protection threshold (VOVP). If an over-voltage condition
occurs, the AAT3686 charge control will shut down the
device until voltage on the BAT pin drops below the overvoltage protection threshold (VOVP). The AAT3686 will
resume normal charging operation after the over-voltage
condition is removed. During an over-voltage event, the
STAT LEDs will report a system fault, and the actual fault
condition may be read via the DATA pin signal.
Over-Temperature Shutdown
The AAT3686 has a thermal protection control circuit
which will shut down charging functions should the internal die temperature exceed the preset thermal limit
threshold.
Battery Temperature Fault Monitoring
In the event of a battery over-temperature condition,
the charge control will turn off the internal pass device
and report a battery temperature fault on the DATA pin
function. The STAT LEDs will also display a system fault.
After the system recovers from a temperature fault, the
device will resume charging operation.
The AAT3686 checks battery temperature before starting the charge cycle, as well as during all stages of
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15
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
charging. This is accomplished by monitoring the voltage
at the TS pin. This system is intended to use negative
temperature coefficient thermistors (NTC), which are
typically integrated into the battery package. Most of the
commonly used NTC thermistors in battery packs are
approximately 10k at room temperature (25°C).
The TS pin has been specifically designed to source 80μA
of current to the thermistor. The voltage on the TS pin
that results from the resistive load should stay within a
window from 335mV to 2.32V. If the battery becomes
too hot during charging due to an internal fault, the
thermistor will heat up and reduce in value, pulling the
TS pin voltage lower than the TS1 threshold and the
AAT3686 will signal the fault condition.
If the use of the TS pin function is not required by the
system, it should be terminated to ground using a 10k
resistor.
the overall thermal power budget for the device package, so it is wise to keep the LED drive current to a
minimum. 2mA should be sufficient to drive most lowcost green or red LEDs. It is not recommended to exceed
8mA for driving an individual status LED.
Event Description
STAT1
STAT2
Charge Disabled or Low Supply
Charge Enabled Without Battery
Battery Charging
Charge Completed
Fault
Off
Flash1
On
Off
On
Off
Flash1
Off
Table 3: Status LED Display Conditions.
The required ballast resistor value can be estimated
using the following formulas:
For connection to the adapter supply:
Battery Charge Status Indication
The AAT3686 indicates the status of the battery under
charge with two different systems. First, the device has
two status LED driver outputs. These two LEDs can indicate simple functions such as no battery charge activity,
battery charging, charge complete, and charge fault. The
AAT3686 also provides a bi-directional data reporting
function so that a system microcontroller can interrogate
the DATA pin and read any one of 22 system states.
Status Indicator Display
Simple system charging status states can be displayed
using one or two LEDs in conjunction with the STAT1 and
STAT2 pins on the AAT3686. These two pins are simple
switches to connect the LED cathodes to ground. It is not
necessary to use both display LEDs if a user simply
wants to have a single lamp to show “charging” or “not
charging.” This can be accomplished by using the STAT1
pin and a single LED. Using two LEDs and both STAT pins
simply gives the user more information to the charging
states. Refer to Table 3 for LED display definitions.
The LED anodes should be connected to either VUSB or
VADP, depending upon system design requirements. The
LEDs should be biased with as little current as necessary
to create reasonable illumination; therefore, a ballast
resistor should be placed between the LED cathodes and
the STAT1/2 pins. LED current consumption will add to
RB(STAT1/2) =
VADP - VF(LED)
ILED(STAT1/2)
Example:
RB(STAT1) =
5.5V - 2.0V
= 1.75kΩ
2mA
Note: Red LED forward voltage (VF) is typically 2.0V @
2mA.
For connection to the USB supply:
RB(STAT1/2) =
VUSB - VF(LED)
ILED(STAT1/2)
Example:
RB(STAT2) =
5.0V - 3.2V
= 900Ω
2mA
Note: Green LED forward voltage (VF) is typically 3.2V @
2mA.
The four status LED display conditions are described in
Table 3.
1. Flashing rate depends on output capacitance.
16
On
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DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Digital Charge Status Reporting
The AAT3686 has a comprehensive digital data reporting
system by use of the DATA pin feature. This function can
provide detailed information regarding the status of the
charging system. The DATA pin is a bi-directional port
which will read back a series of data pulses when the
system microcontroller asserts a request pulse. This single strobe request protocol will invoke one of 22 possible
return pulse counts which the microcontroller can look up
based on the serial report table shown in Table 4.
The DATA pin function is active low and should normally
be pulled high to VADP or VUSB. This data line may also be
pulled high to the same level as the high state for the
logic I/O port on the system microcontroller. In order for
the DATA pin control circuit to generate clean, sharp
Number
DATA Report Status
edges for the data output and to maintain the integrity
of the data timing for the system, the pull-up resistor on
the data line should be low enough in value so that the
DATA signal returns to the high state without delay. If
too small a pull-up resistor is used, the strobe pulse
from the system microcontroller could exceed the maximum pulse time and the DATA output control could issue
false status reports. A 1.5k resistor is recommended
when pulling the DATA pin high to 5.0V on either VADP or
VUSB inputs. If the data line is pulled high to a voltage
level less than 5.0V, the pull-up resistor can be calculated based on a recommended minimum pull-up current of 3mA. Use the following formula:
RPULL-UP ≤
Number
VPULL-UP
3mA
DATA Report Status
1
2
3
4
Chip Over-Temperature Shutdown
Battery Temperature Fault
Over-Voltage Turn Off
Not Used
13
14
15
16
USBH
USBH
USBH
USBH
5
ADP Watchdog Time-Out in Battery Condition Mode
17
USBH End of Charging
6
ADP Battery Condition Mode
18
7
ADP Watchdog Time-Out in Constant Current Mode
19
USBL Battery Condition Mode
USBL Charge End of Charging Reduction in
Constant Current Mode
8
9
ADP Thermal Loop Regulation in Constant Current
Mode
ADP Constant Current Mode
Battery Condition Mode
Charge Reduction in Constant Current Mode
Constant Current Mode
Constant Voltage Mode
20
USBL Constant Current Mode
21
USBL Constant Voltage Mode
10
ADP Watchdog Time-Out in Constant Voltage Mode
22
USBL End of Charging
11
12
ADP Constant Voltage Mode
ADP End of Charging
23
Data Report Error
Table 4: Serial Data Report Table.
1.8V to 5.0V
IN
AAT3686
Status
Control
RPULL_UP
IN
DATA Pin
GPIO
OUT
OUT
μP GPIO
Port
Figure 4: Data Pin Application Circuit.
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17
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Data Timing
The system microcontroller should assert an active low
data request pulse for minimum duration of 200ns; this
is specified by the SQPULSE. Upon sensing the rising edge
of the end of the data request pulse, the AAT3686 status
data control will reply the data word back to the system
microcontroller after a delay defined by the data report
time specification TDATA(RPT). The period of the following
group of data pulses will be defined by the TDATA specification.
Thermal Considerations
The AAT3686 is offered in a 3x4mm TDFN package and a
4x4mm TDFN package, each of which can provide up to
2.7W of power dissipation when it is properly bonded to
a printed circuit board and has a maximum thermal resistance of 37°C/W. Many considerations should be taken
into account when designing the printed circuit board
layout, as well as the placement of the charger IC package in proximity to other heat generating devices in a
given application design. The ambient temperature
around the charger 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:
Eq. 1: PD = (VIN - VBAT) · ICC + VIN · IOP
Where:
PD = Total power dissipation by the device
VIN = Either VADP or VUSB, depending on which mode is
selected
VBAT = Battery voltage as seen at the BAT pin
ICC = Maximum constant fast charge current programmed for the application
IOP = Quiescent current consumed by the charger IC for
normal operation
Next, the maximum operating ambient temperature for
a given application can be estimated based on the thermal resistance of the 3x4mm and 4x4mm TDFN packages when sufficiently mounted to a PCB layout and the
internal thermal loop temperature threshold.
Eq. 2: TA = TJ - ΘJA · PD
Where:
TA = Ambient temperature in °C
TJ = Maximum device junction temperature below the
thermal loop threshold
PD = Total power dissipation by the device
JA = Package thermal resistance in °C/W
Timing Diagram
SQ
SQPULSE
PDATA
System Reset
System Start
CK
TSYNC
Data
18
TLAT
TDATA(RPT) = TSYNC + TLAT < 2.5 PDATA
TOFF > 2 PDATA
TOFF
N=1
N=2
N=3
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DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Example:
Capacitor Selection
For an application where the fast charge current for the
adapter mode is set to 1A, VADP = 5.0V, and the worst
case battery voltage is 3.0V, what is the maximum ambient temperature where the thermal limiting will become
active?
Input Capacitor
Given:
VADP = 5.0V
VBAT = 3.0V
ICC = 1A
IOP = 0.75mA
TJ = 110°C
JA = 37°C/W
Using Equation 3, calculate the device power dissipation
for the stated condition:
Eq. 3: PD = (5.0V - 3.0V) ∙ 1A + 5.0V · 0.75mA
= 2.00375W
The maximum ambient temperature before the AAT3686
thermal loop becomes active can now be calculated
using Equation 4:
Eq. 4:
TA = 110oC - 37°C/W · 2.00375W
= 35.86°C
Therefore, under the stated conditions for this worst
case power dissipation example, the AAT3686 will enter
the thermal loop and lower the fast charge constant current when the ambient operating temperature rises
above 35.86°C.
In general, it is good design practice to place a decoupling capacitor between the VADP and VUSB pins and
ground. An input capacitor in the range of 1μF to 22μF
is recommended. If the source supply is unregulated, it
may be necessary to increase the capacitance to keep
the input voltage above the under-voltage lockout
threshold during device enable and when battery charging is initiated.
If the AAT3686 adapter input is to be used in a system
with an external power supply source, such as a typical
AC-to-DC wall adapter, then a CIN capacitor in the range
of 10μF should be used. A larger input capacitor in this
application will minimize switching or power bounce
effects when the power supply is “hot plugged.” Likewise,
a 10μF or greater input capacitor is recommended for
the USB input to help buffer the effects of USB source
power switching, noise, and input cable impedance.
Output Capacitor
The AAT3686 only requires a 1μF ceramic capacitor on
the BAT pin to maintain circuit stability. This value
should be increased to 10μF or more if the battery connection is made any distance from the charger output. If
the AAT3686 is to be used in applications where the battery can be removed from the charger, such as in the
case of desktop charging cradles, an output capacitor
greater than 10μF may be required to prevent the device
from cycling on and off when no battery is present.
Printed Circuit Board
Layout Considerations
For the best results, it is recommended to physically
place the battery pack as close to the AAT3686 BAT pin
as possible. To minimize voltage drops on the PCB, keep
the high current carrying traces adequately wide. For
maximum power dissipation of the AAT3686 TDFN packages, the metal substrate should be solder bonded to
the board. It is also recommended to maximize the substrate contact to the PCB ground plane layer to further
increase local heat dissipation. Refer to the AAT3686
evaluation board for a good layout example.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
19
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
AAT3686 Evaluation Board Schematic Diagram
Figure 5: AAT3686 Evaluation
Board Component Side Layout.
Figure 6: AAT3686 Evaluation
Board Solder Side Layout.
Figure 7: AAT3686 Evaluation Board Assembly Layout.
20
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
ON/OFF
USBSEL
J1
J2
3
2
1
3
2
1
HI
LO
D4 (b)
USB
BAV74LT1
D4 (a)
ADP
D3
BAV74LT1
R9
R7
R8
R10
1.5K
1.5K
1.5K
1.5K
R6
R11 Open
Open
U1
USB
3
ADP
BAT
EN
6
BAT
C2
C3
10μF
10μF
10μF R12 R1
Open
10K
AAT3686
1
2
C1
GREEN RED
LED
LED
D2
D1
RED
LED
USBSEL
STAT2
STAT1
DATA
5
CHR
7
ADPP#
8
TS
USBH
USBL
ADPSET
GND
4
13
10
11
DATA
9
15
SW1
14
16
R3
CT
R5
R4
C6
8.06K 42.2K 8.06K Open
(Optional)
12
C5
0.1μF
TS
CT
Figure 8: AAT3686 Evaluation Board Schematic Diagram.
AAT3686 Evaluation Board Bill of Materials (BOM)
Quantity
Description
2
Test Pin
2
Conn Term Block 2.54mm 2POS
1
Conn Term Block 2.54mm 3POS
1
USB 2.0 Receptacle, 5POS
Desig.
TS, CT
USB, GND/
ADP, GND
BAT, TS, GND
C1, 2, 3
0805
D1, D3
D2
D4 a, b
J1, 2
R1
R3, 4
R5
R7, 8, 9, 10
1
Switch Tact 6mm SPST H = 5.0mm
1
AAT3686 USB Port/AC Adapter
Lithium-Ion/Polymer Battery Charger
Manufacturer
Part #
Mill-Max
6821-0-0001-00-00-08-0
Phoenix Contact
TBLOK3
USB-MINI-B
2
1
1
2
1
1
1
4
1
TBLOK2
USB
Capacitor, Ceramic, 10μF 6.3V 10%
X5R 0805
Capacitor, Ceramic, 0.1μF 25V 10%
X5R 0603
Typical Red LED
Typical Green LED
Switching Diode
Header, 3-Pin
RES 10kW 1/16W 5% 0603 SMD
RES 8.06kW 1/16W 1% 0603 SMD
RES 42.2kW 1/16W 1% 0603 SMD
RES 1.5kW 1/16W 5% 0603 SMD
3
Footprint
277-1274-ND
277-1273-ND
Hirose Electronic
Co., Ltd.
H2959CT-ND
490-1717-1-ND
Murata
C5
0603
478-1244-2-ND
SOT23-3
Header 2mm-3
Chicago Miniature
Lamp
On Semi
Sullins
0603
Panasonic/ECG
SW1
Switch
ITT Industries/
C&K Div
CKN9012-ND
U1
TDFN34-16;
TDFN44-16
Skyworks
AAT3686IRN-4.2
AAT3686IXN-4.2
1206LED
CMD15-21SRC/TR8
BAV74LT1
6821-0-0001-00-00-08-0
P10KJTR-ND
P9.76KHCT-ND
P42.2KHTR-ND
P1.5KCGCT-ND
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
21
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
Ordering Information
Package
Marking1
Part Number (Tape and Reel)2
TDFN34-16
TDFN44-16
PHXYY
PHXYY
AAT3686IRN-4.2-T1
AAT3686IXN-4.2-T1
Skyworks Green™ products are compliant with
all applicable legislation and are halogen-free.
For additional information, refer to Skyworks
Definition of Green™, document number
SQ04-0074.
Package Information3
TDFN34-16
3.000 ± 0.050
1.600 ± 0.050
Detail "A"
3.300 ± 0.050
4.000 ± 0.050
Index Area
0.350 ± 0.100
Top View
0.230 ± 0.050
Bottom View
C0.3
(4x)
0.050 ± 0.050
0.450 ± 0.050
0.850 MAX
Pin 1 Indicator
(optional)
0.229 ± 0.051
Side View
Detail "A"
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.
22
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
DATA SHEET
AAT3686
USB Port/AC Adapter Li-Ion/Polymer Battery Charger
TDFN44-16
3.30 ± 0.05
Detail "B"
4.00 ± 0.05
Index Area
(D/2 x E/2)
0.3 ± 0.10
0.375 ± 0.125
0.16
0.075 ± 0.075
0.1 REF
4.00 ± 0.05
2.60 ± 0.05
Top View
Pin 1 Indicator
(optional)
0.23 ± 0.05
Bottom View
0.45 ± 0.05
Detail "A"
0.229 ± 0.051
+ 0.05
0.8 -0.20
7.5° ± 7.5°
0.05 ± 0.05
Side View
Detail "B"
Option A:
C0.30 (4x) max
Chamfered corner
Option B:
R0.30 (4x) max
Round corner
Detail "A"
All dimensions in millimeters.
Copyright © 2012 Skyworks Solutions, Inc. All Rights Reserved.
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service to its customers and may be used for informational purposes only by the customer. Skyworks assumes no responsibility for errors or omissions in these materials or the information contained herein. Skyworks may change its documentation, products, services, specifications or product descriptions at any time, without notice. Skyworks makes no commitment to update the materials or information and shall have no
responsibility whatsoever for conflicts, incompatibilities, or other difficulties arising from any future changes.
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THE MATERIALS, PRODUCTS AND INFORMATION ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING FITNESS FOR A PARTICULAR
PURPOSE OR USE, MERCHANTABILITY, PERFORMANCE, QUALITY OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHT; ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. SKYWORKS DOES
NOT WARRANT THE ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS. SKYWORKS SHALL NOT BE LIABLE FOR ANY DAMAGES, INCLUDING BUT NOT LIMITED TO ANY SPECIAL, INDIRECT, INCIDENTAL, STATUTORY, OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS THAT MAY RESULT FROM
THE USE OF THE MATERIALS OR INFORMATION, WHETHER OR NOT THE RECIPIENT OF MATERIALS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Skyworks products are not intended for use in medical, lifesaving or life-sustaining applications, or other equipment in which the failure of the Skyworks products could lead to personal injury, death, physical or environmental damage. Skyworks customers using or selling Skyworks products for use in such applications do so at their own risk and agree to fully indemnify Skyworks for any damages resulting from such improper
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Customers are responsible for their products and applications using Skyworks products, which may deviate from published specifications as a result of design defects, errors, or operation of products outside of published parameters or design specifications. Customers should include design and operating safeguards to minimize these and other risks. Skyworks assumes no liability for applications assistance, customer product
design, or damage to any equipment resulting from the use of Skyworks products outside of stated published specifications or parameters.
Skyworks, the Skyworks symbol, and “Breakthrough Simplicity” are trademarks or registered trademarks of Skyworks Solutions, Inc., in the United States and other countries. Third-party brands and names are for
identification purposes only, and are the property of their respective owners. Additional information, including relevant terms and conditions, posted at www.skyworksinc.com, are incorporated by reference.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
201889B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 25, 2012
23