AAT3783IRN-4.2-T1 - Skyworks Solutions, Inc.

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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

FLT

INCHR TEMP

ENOVP

Enable OVP

OVP

2.2μF

BATS

ADPP

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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 2.2F 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

ENOVP

INCHR

BATS

OVP

FLT

STAT

ISET

GND

TERM

ENCHR

ADPP

EP1

EP2

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Absolute Maximum Ratings1

Symbol Description Value Units

VIN IN continuous 30

VINCHR Charger IN continuous -0.3 to 7.5

VFLT Fault ﬂ ag continuous -0.3 to +30

VNBAT, STAT, ADPP, EN, ISET, TS, ENOVP, OVP -0.3 to VINCHR + 0.3

TJOperating Junction Temperature Range -40 to 150 °C

TLEAD Maximum Soldering Temperature (at Leads) 300

Thermal Information2

Symbol Description Value Units

JA 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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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 48A

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

VCH/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 = 13.3k0.2 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 k, ICH_CC  800mA 8 10 12 %

Battery Charging Device

RDS(ON) Total ON Resistance (IN to BAT) VIN = 5V, IOUT = 1A 550 m

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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 = 1F10 ms

TOVPR OVP Turn-On Rise Time Charging current = 500mA,

CINCHR = 1F1ms

TOVPOFF OVP Turn-Off Delay Time Charging current = 500mA,

CINCHR = 1F6s

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Typical Characteristics

Constant Charging Current

vs. Set Resistor Values

RSET (mA)

Constant Charging Current (mA)

100

1000

10000

1 10 100 100

Battery Charging Current

vs. Battery Voltage

Battery Voltage (V)

Charging Current (mA)

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

0.05

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)

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Typical Characteristics

Preconditioning Charge Current vs. Temperature

(RSET = 8.06kΩ; ICH_CC = 200mA)

Temperature (°C)

Preconditioning Charge Current (mA)

-40 -15 10 35 60 8

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

Constant Charging Current vs. Input Voltage

(RSET = 1.62kΩ

)

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

)

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

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Typical Characteristics

Temperature Sense Output Current

vs. Temperature

Temperature (°C)

ITS (mV)

-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 (%)

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Typical Characteristics

FLT Blanking Time

Time (2ms/div)

Input Voltage (V)

FLT Voltage (V)

-4

-2

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

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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

FLT

ENCHR

INCHR

BAT S

CV/ Pre -

Charge

TERM

OVP

Over-Current

Protection

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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 1s 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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

System Operation Flow Chart

CH>V

BAT

MIN>V

BAT

Shut Down

Mode

Shut Down

Mode

BAT

> I

MIN

Charge

Completed

Charge

Completed

Recharge

Test

RCH

> V

BAT

Yes

Device Temp.

Monitor

TJ>110 C

Yes

ADP

Voltage

ADP > V

ADPP

Preconditioning

Test

VMIN>VBAT

Current Phase Test

VIN>VBAT_EOC

Voltage Phase Test

IBAT>ITERM

Shut Down

Mode

Shutdown

Mode

Charge

Completed

Charge

Completed

Recharge

Test

VRCH > VBAT

Yes

Enable

Expire

Yes

Device Temp.

Monitor

J>115 C

Yes

Fault

Yes

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

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

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

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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

)

Constant Charging Current (mA)

100

1000

10000

1 10 100 1000

Figure 2: Constant Charging Current

vs. Set Resistor Values.

AAT3783

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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

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 0.1F ceramic capacitor is connected

between the CT pin and ground. When a 0.1F 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 0.1F 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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

istors in battery packs are approximately 10k at room

temperature (25°C). The TS pin has been specifically

designed to source 75A 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:

J(MAX) -

)

D(MAX)

= θ

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)

0.5

1.5

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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.

D(MAX) -

)

- V

BAT

CH(MAX)

J(MAX) -

)

CH(MAX)

- 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)

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 1F 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 2.2F decoupling capacitor is recommended to be

placed between INCHR and GND.

Charger Output Capacitor

The AAT3783 only requires a 1F ceramic capacitor on

the BAT pin to maintain circuit stability. This value should

be increased to 10F 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 10F 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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

(op en)

1μF

Enable

JP1

+5V

Red LED

2.2μF

INCHR

EN_CHR

JP2 0.1μF

C4 13.3k

1.62k

INCHR

1.5k

Red LED

1.5k

Green LED

10k

10μF

INCHR

JP3

(open)

BAT

GND

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

GND

TS 4

STAT 8

ENCHR

FLT

BATS 2

BAT 3

OVP

ISET 14

TERM 12

ADPP 9

INCHR

CT 10

AAT3783

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

Skyworks

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 1F 50V 10% X7R 1206 Murata

C2 GRM188R61A225KE34 CER 2.2F 10V 10% X5R 0805 Murata

C3 GRM21BR71A106KE51L CER 10F 10V 10% X7R 0805 Murata

C4 GRM188R71E104KA01 CER 0.1F 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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

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

DATA SHEET

1-A Linear Li-Ion/Polymer Battery Charger with 28V Over-Voltage Protection

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

201903B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • April 27, 2012

Information in this document is provided in connection with Skyworks Solutions, Inc. (“Skyworks”) products or services. These materials, including the information contained herein, are provided by Skyworks as a

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. Sky-

works may change its documentation, products, services, speciﬁ cations 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 conﬂ icts, incompatibilities, or other difﬁ culties arising from any future changes.

No license, whether express, implied, by estoppel or otherwise, is granted to any intellectual property rights by this document. Skyworks assumes no liability for any materials, products or information provided here-

under, including the sale, distribution, reproduction or use of Skyworks products, information or materials, except as may be provided in Skyworks Terms and Conditions of Sale.

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, IN-

CLUDING 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 en-

vironmental 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

use or sale.

Customers are responsible for their products and applications using Skyworks products, which may deviate from published speciﬁ cations as a result of design defects, errors, or operation of products outside of pub-

lished parameters or design speciﬁ cations. 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 speciﬁ cations 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

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Ordering Information

Package Marking1Part Number (Tape and Reel)2

TDFN34-16 XQXYY AAT3783IRN-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 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.