LTC4063
1
4063fc
Typical applicaTion
FeaTures DescripTion
Standalone Linear Li-Ion
Charger with Micropower
Low Dropout Linear Regulator
The LTC
®
4063 is a standalone linear charger for single cell
lithium-ion batteries with an adjustable low dropout linear
regulator (LDO). The adjustable LDO regulates an output
voltage between 1.2V to 4.2V at up to 100mA load cur-
rent. When the input supply (wall adapter or USB supply)
is removed, the LDO regulates the output voltage without
interruption. The battery charger and LDO regulator can
be enabled individually.
No external sense resistor or external blocking diode is
required for charging due to the internal MOSFET archi-
tecture. Internal thermal feedback regulates the charge
current to maintain a constant die temperature during high
power operation or high ambient temperature conditions.
The float voltage is fixed at 4.2V and the charge current is
programmed with an external resistor. Charge termination
methods include minimum charge current or maximum
time. With power applied, the LTC4063 can be put into
shutdown mode to reduce the supply current to 35µA and
the battery drain current to less than 2µA.
Other features include smart recharge, undervoltage
lockout, LDO current limiting and a charge status pin to
indicate when the charge cycle has completed.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
SmartStart, ThinSOT and PowerPath are trademarks of Linear Technology Corporation. All
other trademarks are the property of their respective owners. Protected by U.S. Patents
including 6522118.
applicaTions
n Charge Current Programmable up to 1A
n Integrated 100mA Adjustable Low Dropout Linear
Regulator
n Charges Single Cell Li-Ion Batteries Directly from
USB Port
n Preset Charge Voltage with ±0.35% Accuracy
n No External MOSFET, Sense Resistor or Blocking
Diode Needed
n Thermal Regulation Maximizes Charge Rate
without Risk of Overheating
n Adjustable LDO Output Voltage Range:
1.2V to 4.2V
n Programmable Charge Termination Timer
n Programmable Charge Current Detection/Termination
n SmartStart™ Prolongs Battery Life
n Charge Status Output
n 35µA Charger Quiescent Current in Shutdown
n 15µA LDO Quiescent Current
n Available in a Low Profile (0.75mm) 10-Lead
(3mm × 3mm) DFN Package
n Handheld Computers
n Portable MP3 Players
n Digital Cameras
Single Cell Li-Ion Battery Charger with Regulated 3V Output
(C/10 Termination)
Complete Charge Cycle (900mAh Battery)
+
VCC
TIMER
PROG
IDET
BAT
OUT
FB
LTC4063
GND
440k
700mA
160k
715Ω
2.2µF
1µF
VIN
4.3V TO 8V
4063 TA01a
VOUT
3V
4.2V
SINGLE CELL
Li-Ion BATTERY
TIME (HOURS)
0
CHARGE CURRENT (mA)
BATTERY VOLTAGE (V)
400
500
600
2
4063 TA01b
300
200
00.50 11.50
0.25 2.25
0.75 1.25 1.75
100
800
700
3.75
4.00
4.25
3.50
3.25
2.75
3.00
4.75
4.50
CONSTANT CURRENT
CONSTANT
VOLTAGE
VCC = 5V
TA = 25°C
LTC4063
2
4063fc
pin conFiguraTionabsoluTe MaxiMuM raTings
Input Supply Voltage (VCC) ........................ –0.3V to 10V
CHGEN, LDOEN, CHRG .............................. –0.3V to 10V
FB ................................................................ –0.3V to 8V
PROG, IDET, TIMER ........................ –0.3V to VCC + 0.3V
BAT, OUT ...................................................... –0.3V to 8V
BAT Short-Circuit Duration ...........................Continuous
OUT Short-Circuit Duration ...........................Continuous
BAT Pin Current (Note 8) ............................................1A
Maximum Junction Temperature (Note 7) ............ 125°C
Operating Temperature Range (Note 2) ...–40°C to 85°C
Storage Temperature Range .................. –65°C to 125°C
(Note 1)
TOP VIEW
11
DD PACKAGE
10-LEAD (3mm s 3mm) PLASTIC DFN
10
9
6
7
8
4
5
3
2
1VCC
PROG
IDET
TIMER
CHRG
BAT
OUT
FB
LDOEN
CHGEN
TJMAX = 125°C, θJA = 40°C/W (NOTE 3)
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC4063EDD#PBF LTC4063EDD#TRPBF LBHX 10-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
elecTrical characTerisTics
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VCC VCC Supply Voltage l4.3 8 V
ICC ICC Supply Current Charge Mode (Note 4), RPROG = 10k
Standby Mode, Charge Terminated
Shutdown (CHGEN = 5V, VCC < VBAT or VCC < VUV)
CHGEN = 5V and LDOEN = 5V
l
l
l
l
400
100
35
15
800
200
65
30
µA
µA
µA
µA
VFLOAT VBAT Regulated Output Voltage
0°C ≤ TA ≤ 85°C 4.185
4.170 4.2
4.2 4.215
4.230 V
V
IBAT BAT Pin Current (Note 5) RPROG = 10k, Constant-Current Mode
RPROG = 1.25k, Constant-Current Mode
Standby Mode, Charge Terminated
Shutdown Mode (CHGEN = 5V, LDOEN = 5V)
l
l
l
l
93
760 100
800
–3.5
±1
107
840
–7
±2
mA
mA
µA
µA
VPROG PROG Pin Voltage RPROG = 10k, Constant-Current Mode
RPROG = 1.25k, Constant-Current Mode 0.97
0.97 1
11.03
1.03 V
V
VCHRG CHRG Output Low Voltage ICHRG = 5mA 0.35 0.6 V
ITRIKL Trickle Charge Current VBAT < VTRIKL, RPROG = 10k
VBAT < VTRIKL, RPROG = 1.25k 6
60 10
80 14
100 mA
mA
VTRIKL Trickle Charge Threshold Voltage VBAT Rising
Hysteresis 2.8 2.9
100 3 V
mV
VUV VCC Undervoltage Lockout Voltage From Low to High
Hysteresis 3.7 3.8
200 3.9 V
mV
VASD VCC – VBAT Lockout Threshold Voltage VCC from Low to High, VBAT = 4.2V
VCC from High to Low, VBAT = 4.2V 145
10 180
45 220
75 mV
mV
VCHGEN CHGEN Input Threshold Voltage CHGEN Rising, 4.3V < VCC < 8V
Hysteresis 0.4 0.7
100 1 V
mV
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, unless otherwise noted.
LTC4063
3
4063fc
elecTrical characTerisTics
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC4063EDD is guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 3: Failure to correctly solder the Exposed Pad of the package to the
PC board will result in a thermal resistance much higher than 40°C/W.
Note 4: Supply current includes PROG pin current and IDET pin current
(approximately 100µA each) but does not include any current delivered to
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
RCHGEN CHGEN Pin Pull-Down Resistor l1.2 2 5 MΩ
VCT Charge Termination Mode Threshold
Voltage
VTIMER from High to Low
Hysteresis
0.4 0.7
100
1 V
mV
VUT User Termination Mode Threshold Voltage VTIMER from Low to High
Hysteresis
4.15 4.1
100
4.5 V
mV
IDETECT Charge Current Detection Threshold RDET = 1k, 0°C ≤ TA ≤ 85°C
RDET = 2k, 0°C ≤ TA ≤ 85°C
RDET = 10k, 0°C ≤ TA ≤ 85°C
RDET = 20k, 0°C ≤ TA ≤ 85°C
90
45
8.5
4
100
50
10
5
110
55
11.5
6
mA
mA
mA
mA
∆VRECHRG Recharge Threshold Voltage VFLOAT – VRECHRG, 0°C ≤ TA ≤ 85°C 75 100 125 mV
tTERM Termination Comparator Filter Time Current Termination Mode 1 1.5 2.2 ms
tRECHRG Recharge Comparator Filter Time 3 7 14 ms
tTIMER Charge Cycle Time CTIMER = 0.1µF 2.55 3 3.45 Hour
tSS Soft-Start Time IBAT from 0 to ICHG 100 µs
TLIM Junction Temperature in Constant
Temperature Mode
105 °C
RON Power FET On-Resistance
(Between VCC and BAT)
375 mΩ
VBAT-LDO LDO Supply Voltage (BAT) 2.65 4.4 V
IBAT-LDO LDO Supply Current (from BAT) VCC < VBAT
, IOUT = 0mA
VCC > VBAT
, IOUT = 0mA (Note 6)
15
9
25
18
µA
µA
IBAT-LDO-SD LDO Supply Current in Shutdown VBAT = 4.4V 2.5 5 µA
VFB FB Regulated Voltage VBAT = 3.7V, IOUT = 1mA l784 800 816 mV
VFB(LINE) VFB Line Regulation VBAT = 2.65V to 4.4V, IOUT = 1mA l1 4 mV
VFB(LOAD) VFB Load Regulation IOUT = 1mA to 100mA, VBAT = 4.4V l1 4 mV
VLDOEN LDOEN Input Threshold Voltage (Rising) LDOEN Rising, VBAT = 4.4V
Hysteresis
0.4 0.7
100
1 V
mV
RLDOEN LDOEN Pin Pull-Down Resistor l1.2 2 5 MΩ
VDO LDO Dropout Voltage IOUT = 100mA, VOUT = 3V 125 200 mV
VLDOUVLO LDO Undervoltage Lockout Threshold VBAT from High to Low
Hysteresis
2.45 2.55
100
2.65 V
mV
IFB FB Pin Current –25 0 25 nA
ISC Short-Circuit Output Current VOUT = 0V 500 mA
VNO(RMS) Output Voltage Noise VOUT = 3V, IOUT = 100mA, COUT = 2.2µF,
10Hz ≤ f ≤ 100kHz
135 µVRMS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, unless otherwise noted.
the battery through the BAT pin (approximately 100mA).
Note 5: Does not include LDO supply current.
Note 6: The LDO is partially powered from VCC, thus reducing the supply
current from the BAT pin.
Note 7: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions.
Overtemperature protection will become active at a junction temperature
greater than the maximum operating temperature. Continuous operation
above the specified maximum operating junction temperature may impair
device reliability.
Note 8: Defined by long term current density limitations.
LTC4063
4
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Typical perForMance characTerisTics
CHARGE CURRENT (mA)
0
VFLOAT (V)
4.18
4.22
800
4063 G01
4.14
4.10 200 400 600
100 300 500 700
4.26
4.16
4.20
4.12
4.24
VCC = 5V
RPROG = 1.25k
TEMPERATURE (°C)
–50
4.185
VFLOAT (V)
4.190
4.195
4.200
4.205
4.215
–25 0 25 50
4063 G02
75 100
4.210
RPROG = 10k
VCC = 8V
VCC = 4.3V
TEMPERATURE (°C)
–50
0.994
VPROG (V)
0.996
0.998
1.000
1.002
1.006
–25 0 25 50
4063 G03
75 100
1.004
RPROG = 10k
VCC = 8V
VCC = 4.3V
VPROG (V)
0
0
IBAT (mA)
100
300
400
500
0.8
900
4063 G04
200
0.4
0.2 1.0
0.6 1.2
600
700
800
VCC = 5V
RPROG = 1.25k
VTIMER = 5V
TEMPERATURE (°C)
–50
tTIMER (MINUTES)
185
190
195
25 75
4063 G05
180
175
–25 0 50 100 125
170
165
CTIMER = 0.1µF
VCC = 4.3V
VCC = 8V
VCHRG (V)
0
20
25
3 5
4063 G06
15
10
1 2 4 6 7
5
0
30
35
ICHRG (mA)
VCC = 5V
VBAT = 4V TA = –40°C
TA = 90°C
TA = 25°C
TEMPERATURE (°C)
–50
2.84
VTRIKL (V)
2.86
2.88
2.90
2.92
2.96
–25 0 25 50
4063 G08
75 100
2.94
VCC = 5V
RPROG = 1.25k
VBAT (V)
2.7
0
IBAT (mA)
200
400
600
800
1000
33.3 3.6 3.9
4063 G09
4.2 4.5
VCC = 5V
RPROG = 1.25k
QJA = 40oC/W
Regulated Output (Float) Voltage
vs Charge Current
Regulated Output (Float) Voltage
vs Temperature
Internal Charge Timer
vs Temperature
Charge Current
vs PROG Pin Voltage
Trickle Charge Current
vs Temperature
Trickle Charge Threshold Voltage
vs Temperature Charge Current vs Battery Voltage
PROG Pin Voltage vs Temperature
(Constant-Current Mode)
CHRG Pin I-V Curve
TA = 25°C, unless otherwise noted.
LTC4063
5
4063fc
Typical perForMance characTerisTics
Charge Current vs Supply Voltage
Recharge Threshold Voltage
vs Temperature
Power FET On-Resistance
vs Temperature Shutdown Current vs Temperature
CHGEN Pin Threshold Voltage
(On-to-Off) vs Temperature
CHGEN Pin Pull-Down Resistance
vs Temperature
Charge Current
vs Ambient Temperature
FB Pin Regulated Voltage
vs Output Current
FB Pin Regulated Voltage
vs Temperature
TEMPERATURE (°C)
–50 –25
0
IBAT (mA)
400
1000
050 75
4063 G10
200
800
600
25 100 125
RPROG = 1.25k
ONSET OF THERMAL
REGULATION
RPROG = 2k
VCC = 5V
VBAT = 4V
QJA = 40°C/W
VCC (V)
4
300
IBAT (mA)
400
500
600
700
5 6 78
4063 G11
800
900
4.5 5.5 6.5 7.5
RPROG = 1.25k
VBAT = 3.3V
QJA = 35°C/W
TA = 25°C
ONSET OF THERMAL
REGULATION
TEMPERATURE (oC)
–50
4.04
VRECHRG (V)
4.06
4.08
4.10
4.12
4.16
–25 0 25 50
4063 G12
75 100
4.14
VCC = 4.3V
VCC = 8V
TEMPERATURE (°C)
–50
RDS(ON) (mΩ)
550
600
650
25 75
4063 G13
500
450
–25 0 50 100 125
400
350
VBAT = 4V
IBAT = 200mA
RPROG = 1.25k
TEMPERATURE (°C)
–50
VCHGEN (mV)
800
850
900
25 75
4063 G15
750
700
–25 0 50 100 125
650
600
VCC = 5V
IOUT (mA)
0
797
VFB (mV)
798
799
800
801
803
20 40 60 80
4063 G17
100 120
802
VBAT = 4.2V
TA = 25°C
TA = 90°C
TA = 115°C
TA = –40°C
TEMPERATURE (°C)
–50
VFB (V)
801
802
803
25 75
4063 G18
800
799
–25 0 50 100 125
798
797
ILOAD = 1mA
VBAT = 4.2V
VBAT = 2.65V
TA = 25°C, unless otherwise noted.
LTC4063
6
4063fc
TEMPERATURE (°C)
–50
0
VDROPOUT (mV)
50
100
150
200
–25 0 25 50
4063 G19
75 100
VOUT = 3V
IOUT = 100mA
TEMPERATURE (°C)
–50
IBAT (µA)
15
20
25
75
4060 G20
10
5
0–25 0 25 50 100
VBAT = 4.2V
VBAT = 2.65V
FREQUENCY (Hz)
0.1
OUTPUT NOISE SPECTRAL DENSITY (µV/√Hz)
1
10 1k 10k 100k
4063 G24
0.01 100
10
LOAD CURRENT (mA)
0
0
VDROPOUT (mV)
30
60
90
120
180
20 40 60 80
4063 G26
100 120
150
VOUT = 3V
TA = 115°C
TA = 90°C
TA = –40°C
TA = 25°C
TEMPERATURE (°C)
–50
VLDOEN (mV)
800
850
900
25 75
4063 G22
750
700
–25 0 50 100 125
650
600
VBAT = 4V
VOUT
500µV/
DIV
4063 G21
135µVRMS
10ms/DIVCOUT = 2.2µF
ILOAD = 100mA
VOUT = 3V
OUTPUT
VOLTAGE
DEVIATION
50mV/DIV
LOAD
CURRENT
50mA/DIV
4063 G25
50µs/DIVCOUT = 2.2µF
VOUT = 1.2V
Typical perForMance characTerisTics
LDO Regulator Dropout Voltage
vs Temperature
LDO Regulator Dropout Voltage
vs Load Current
LDO Regulator Quiescent Current
vs Temperature
LDO Regulator 10Hz to 100kHz
Output Noise
LDO Regulator Transient
Response
LDOEN Pin Threshold (On-to-Off)
vs Temperature
LDO Regulator Output Noise
Spectral Density
LDOEN Pin Pull-Down Resistance
vs Temperature
TA = 25°C, unless otherwise noted.
LTC4063
7
4063fc
pin FuncTions
BAT (Pin 1): Charger Output and Regulator Input. This pin
provides charge current to the battery and regulates the
final float voltage to 4.2V. This pin also supplies power to
the LDO regulator.
OUT (Pin 2): LDO Regulator Output. This pin should be
bypassed with a ≥2µF low ESR capacitor as close to the
pin as possible for best performance. The minimum VOUT
is 1.2V.
FB (Pin 3): Regulator Feedback Input. The voltage on this
pin is compared to the internal reference voltage (800mV)
by the error amplifier to keep the output voltage in regula-
tion. An external resistor divider between OUT and FB sets
the output voltage.
LDOEN (Pin 4): LDO Enable Input. A logic high on the
LDOEN pin shuts down the LDO. In this state, OUT becomes
high impedance and the battery drain current drops to
less than 5µA. A logic low on the LDOEN pin enables the
LDO regulator. A 2M pull-down resistor defaults the LDO
to its enabled state.
CHGEN (Pin 5): Charger Enable Input. A logic high on the
CHGEN pin places the charger into shutdown mode, where
the ICC quiescent current is less than 65µA. A logic low on
this pin enables battery charging. A 2M pull-down resistor
to ground defaults the charger to its enabled state.
CHRG (Pin 6): Open-Drain Charge Status Output. The
charge status indicator pin has two states: pull-down
and high impedance. This output can be used as a logic
interface or an LED driver. In the pull-down state, an
NMOS transistor capable of sinking 10mA pulls down on
the CHRG pin. The state of this pin is dependent on the
value of IDETECT as well as the termination method being
used. See Applications Information.
TIMER (Pin 7): Timer Program and Termination Select Pin.
This pin selects which method is used to terminate the
charge cycle. Connecting a capacitor, CTIMER, to ground
selects Charge Time termination. The charge time is set
by the following formula:
Time Hours Hours C
µF or
C µF Ti
TIMER
TIMER
( ) • .
. •
=
=
30 1
0 1 mme Hours
Hours
( )
( )3
Connecting the pin to ground selects Charge Current
termination, while connecting the pin to VCC selects User
termination. See Applications Information.
IDET (Pin 8): Current Detection Threshold Program Pin.
The current detection threshold, IDETECT, is set by con-
necting a resistor, RDET, to ground. IDETECT is set by the
following formula:
IR
RIV
Ror
RV
I
DETECT PROG
DET CHG DET
DET DE
= =
=
10
100
100
•
TTECT
The CHRG pin becomes high impedance when the charge
current drops below IDETECT
. IDETECT can be set to 1/10th
the programmed charge current by connecting IDET directly
to PROG. See Applications Information.
This pin is clamped to approximately 2.4V. Driving this
pin to voltages beyond the clamp voltage can draw large
currents and should be avoided.
PROG (Pin 9): Charge Current Program and Charge Cur-
rent Monitor. The charge current is set by connecting a
resistor, RPROG, to ground. When charging in constant
current mode, this pin servos to 1V. The voltage on this
pin can be used to measure the charge current using the
following formula:
IV
R
BAT PROG
PROG
=•1000
VCC (Pin 10): Positive Input Supply Pin. Provides power
to the battery charger. This pin should be bypassed with
a 1µF capacitor.
GND (Exposed Pad Pin 11): Ground. This pin is the back
of the Exposed Pad package and must be soldered to the
PCB copper for minimal thermal resistance.
LTC4063
8
4063fc
block DiagraM
–
+
–
+
–+
–
+
11987
2
CA
MA
1.2V 800mV
2.9V
PROGIDET
RDET
CTIMER RPROG
0.1V TO BAT
1V
3µA
0.1V
–
+–+
C3C2
LOGIC
VCC
TA
TDIE
105°C
SHDN
4063 BD
GND
–+
VA RA R1
R2
BAT
1000s1s1s
VCC
OUT
3
FB
1
10
TERM
RECHRG
4.1V
TO BAT
CHGEN
2MΩ
SEL
TIMER
COUNTER
OSCILLATOR
CHGEN
LDOEN
LDOEN
STOP
CHRG
2MΩ
6
4
5
–
+
C1
LTC4063
9
4063fc
operaTion
The LTC4063 is designed to charge a single cell lithium-
ion battery and supply a regulated output voltage for
battery-powered applications. Using the constant current/
constant voltage algorithm, the charger can deliver up to
1A of charge current with a final float voltage accuracy of
±0.35%. The LTC4063 includes an internal P-channel power
MOSFET and thermal regulation circuitry. No blocking
diode or external sense resistor is required; thus, the basic
charger circuit requires only two external components.
The LDO regulator is powered from the battery terminal
and can be programmed for output voltages between 1.2V
and 4.2V using external resistors. An output capacitor is
required on the OUT pin for stability and improved transient
response. A low ESR capacitor of ≥2µF should be used.
Normal Operation
The charge cycle begins when the voltage at the VCC pin
rises above the UVLO level and a discharged battery is
connected to BAT. If the BAT pin voltage is below 2.9V,
the charger enters trickle charge mode. In this mode,
the LTC4063 supplies 1/10th of the programmed charge
current in order to bring the battery voltage up to a safe
level for full current charging.
Once the BAT pin voltage rises above 2.9V, the charger
enters constant-current mode where the programmed
charge current is supplied to the battery. When the BAT
pin approaches the final float voltage (4.2V), the LTC4063
enters constant-voltage mode and the charge current
decreases as the battery becomes fully charged.
The LTC4063 offers several methods with which to ter-
minate a charge cycle. Connecting an external capacitor
to the TIMER pin activates an internal timer that stops
the charge cycle after the programmed time period has
elapsed. Grounding the TIMER pin and connecting a resis-
tor to the IDET pin causes the charge cycle to terminate
once the charge current falls below a set threshold when
the charger is in constant-voltage mode. Connecting the
TIMER pin to VCC disables internal termination, allowing
external charge termination to be used by the CHGEN
input. See Applications Information for more on charge
termination methods.
Programming the Charge Current
The charge current is programmed using a single resistor
from the PROG pin to ground. The battery charge cur-
rent is 1000 times the current out of the PROG pin. The
program resistor and the charge current are calculated by
the following equations:
RV
IIV
R
PROG CHG CHG PROG
= =
1000 1000
,
The charge current out of the BAT pin can be determined
at any time by monitoring the PROG pin voltage and ap-
plying the following equation:
IV
R
BAT PROG
PROG
=• 1000
SmartStart
When the LTC4063 is initially powered on or brought out
of shutdown mode, the charger checks the voltage on
BAT. If the BAT pin is below the recharge threshold of 4.1V
(which corresponds to approximately 80% to 90% battery
capacity), the LTC4063 enters charge mode and begins a
full charge cycle. If the BAT pin is above 4.1V, the LTC4063
enters standby mode and does not begin charging. This
feature reduces the number of unnecessary charge cycles,
prolonging battery life.
Automatic Recharge
When the charger is in standby mode, the LTC4063
continuously monitors the voltage on the BAT pin. When
the BAT pin voltage drops below 4.1V, the charge cycle is
automatically restarted and the internal timer is reset to
50% the programmed charge time (if time termination is
being used). This feature eliminates the need for periodic
charge cycle initiations and ensures that the battery is
always fully charged. Automatic recharge is disabled in
User Termination mode.
Thermal Regulation
An internal thermal feedback loop reduces the programmed
charge current if the die temperature attempts to rise
above a preset value of approximately 105°C. This feature
LTC4063
10
4063fc
operaTion
protects the LTC4063 from excessive temperature and
allows the user to push the limits of the power handling
capability of a given circuit board without risk of damaging
the LTC4063. The charge current can be set according to
typical (not worst-case) ambient temperatures with the
assurance that the charger will automatically reduce the
current in worst-case conditions.
Undervoltage Lockout (UVLO)
An internal undervoltage lockout circuit monitors the
input voltage and keeps the charger in shutdown mode
until VCC rises above the undervoltage lockout threshold
(3.8V). The UVLO circuit has a built-in hysteresis of
200mV. Furthermore, to protect against reverse current in
the power MOSFET, the UVLO circuit keeps the charger in
shutdown mode if VCC falls to less than 45mV above the
battery voltage. Hysteresis of 135mV prevents the charger
from cycling in and out of shutdown.
Manual Shutdown
At any point in the charge cycle, the charger can be put
into shutdown mode by pulling the CHGEN pin high. This
reduces the supply current to less than 65µA and the
battery drain current of the charger to less than 2µA. A
new charge cycle can be initiated by pulling the CHGEN
pin low.
Pulling the LDOEN pin high puts the LDO into shutdown
mode reducing the battery drain current of the LDO to less
than 5µA. When both the CHGEN and LDOEN pins are pulled
high, the total battery drain current from the LTC4063 is
less than 2µA. If shutdown is not required, leaving these
pins disconnected continuously enables the circuit.
T
rickle Charge and Defective Battery Detection
When the BAT pin voltage is below the 2.9V trickle charge
threshold (VTRIKL), the charger reduces the charge current
to 10% of the programmed value. If the battery remains in
trickle charge for more than 25% of the total programmed
charge time, the charger stops charging and enters a FAULT
state, indicating that the battery is defective.1 The LTC4063
indicates the FAULT state by driving the CHRG open-drain
output with a square wave. The duty cycle of this oscillation
is 50% and the frequency is set by CTIMER:
fµF
CHz
CHRG TIMER
=0 1 3 1
.• .
An LED driven by the CHRG output exhibits a blinking
pattern, indicating to the user that the battery needs
replacing. To exit the FAULT state, the charger must be
restarted either by toggling the CHGEN input or removing
and reapplying power to VCC.
Charge Status Output (CHRG)
The charge status indicator pin has two states: pull-down
and high impedance. In the pull-down state, an NMOS
transistor pulls down on the CHRG pin and can sink up
to 10mA. A pull-down state indicates that the LTC4063 is
charging a battery and the charge current is greater than
IDETECT (which is set by the external resistor RDET). A high
impedance state indicates that the charge current has
dropped below IDETECT. In the case where the IDET pin is
left open (RDET = ∞, IDETECT = 0), a high impedance state
on CHRG indicates that the LTC4063 is not charging.
Low Dropout Linear Regulator (LDO)
The OUT pin provides a stable, regulated output voltage
powered from the battery. This output can power devices
such as memory or USB controllers from the battery when
there is no power applied to VCC.
The LDO can deliver 100mA of current with a nominal
dropout voltage of 150mV. It is designed to be stable
with a low ESR capacitor greater than 2µF on the OUT
pin. Furthermore, the LDO is capable of operating from
a Li-Ion battery voltage as low as 2.65V with less than
300mV of dropout over the specified operating conditions.
An undervoltage lockout circuit automatically disables the
LDO when the battery voltage drops below 2.55V, reducing
the battery drain current to less than 5µA. The LDO can
be disabled by pulling the LDOEN pin high, reducing the
battery quiescent current to less than 5µA.
1 The defective battery detection feature is only available when time termination is being used.
LTC4063
11
4063fc
operaTion
Figure 1. Adjustable Linear Regulator
applicaTions inForMaTion
Programming Charge Termination
The LTC4063 terminates a charge cycle using several
methods, allowing the designer considerable flexibility in
choosing an ideal charge termination algorithm. Table 1
shows a brief description of the different termination
methods and their behavior.
Charge Time Termination
Connecting a capacitor (CTIMER) to the TIMER pin enables
the timer and selects Charge Time Termination. The total
charge time is set by:
Time Hours C
µF Hours
TIMER
( ) .•=0 1 3
When the programmed time has elapsed, the charge
cycle terminates and the charger enters standby mode.
Subsequent recharge cycles terminate when half the
programmed time has elapsed.
The IDET pin determines the behavior of the CHRG output.
Connecting a resistor (RDET) from the IDET pin to ground
sets the charge current detection threshold, IDETECT:
IR
RIV
R
or
RV
I
DETECT PROG
DET CHG DET
DET DE
= =
=
10
100
100
•
TTECT
Table 1.
METHOD
Charge Time
Termination
Charge Current
Termination
TIMER
0.1µF to
GND
IDET
RDET to
GND
CHARGER DESCRIPTION
Charges for 3 Hours. After 3 Hours, the Charger
Stops Charging and Enters Standby Mode.
Recharge Cycles Last for 1.5 Hours
Charges for 3 Hours. After 3 Hours, the Charger
Stops Charging and Enters Standby Mode.
Recharge Cycles Last for 1.5 Hours
Charges Until Charge Current Drops Below
IDETECT, Then Enters Standby Mode
Pull-Down State When Charging. High Impedance State
When Charging is Stopped
Pull-Down State When Charging. High Impedance State
When Charging is Stopped
CHRG OUTPUT DESCRIPTION
Pull-Down State While IBAT > IDETECT. High Impedance
State While IBAT < IDETECT or When Charging is Stopped
Pull-Down State While IBAT > IDETECT. High Impedance
State While IBAT < IDETECT or When Charging is Stopped
0.1µF to
GND
GND RDET to
GND
User-Selectable
Charge
Termination
VCC RDET to
GND
Charges Indefinitely Until CHGEN Pin is Pulled
High
VCC NC
Pull-Down State When Charging. High Impedance State
When Charging is Stopped
Pull-Down State When Charging. High Impedance State
When Charging is Stopped
GND NC
NC
Charges Indefinitely Until CHGEN Pin is Pulled
High. SmartStart is Disabled
Charges Indefinitely Until CHGEN Pin is Pulled
High. SmartStart is Disabled
Figure 1 shows how an external resistor divider sets the
regulator output voltage. The output voltage can be set
anywhere between 1.2V and 4.2V, although the upper
limit is limited by the battery voltage minus the regulator
dropout voltage.
V mV R
R
OUT = +
800 1 2
1
•
In order to maintain stability under light load conditions,
the maximum recommended value of R1 is 160k.
+
BAT
R2
COUT
SINGLE CELL
Li-Ion BATTERY
VOUT
R1
4063 F01
OUT
FB
LTC4063
GND
LTC4063
12
4063fc
applicaTions inForMaTion
When the charge current (IBAT) is greater than IDETECT, the
CHRG output is in its pull-down state. When the charger
enters constant-voltage mode operation and the charge
current falls below IDETECT, the CHRG output becomes
high impedance, indicating that the battery is almost
fully charged. The CHRG output will also become high
impedance once the charge time elapses. If the IDET pin
is not connected, the CHRG output remains in its pull-
down state until the charge time elapses and terminates
the charge cycle.
Figure 2 shows a charger circuit using charge time termi-
nation that is programmed to charge at 500mA. Once the
charge current drops below 100mA in constant-voltage
mode (as set by RDET), the CHRG output turns off the
LED. This indicates to the user that the battery is almost
fully charged and ready to use. The LTC4063 continues to
charge the battery until the internal timer reaches 3 hours
(as set by CTIMER). During recharge cycles, the LTC4063
charges the battery until the internal timer reaches 1.5
hours. Figure 3 describes the operation of the LTC4063
charger when Charge Time Termination is used.
+
VCC
CHRG
PROG
IDET CTIMER
0.1µF
VIN
4063 F02
BAT 500mA
TIMER
RDET
1k
RPROG
2k
LTC4063
GND
Figure 2. Charge Time Termination. The Charger
Automatically Shuts Off After 3 Hours
CHARGE MODE
FULL CURRENT
CHRG STATE:
PULL-DOWN IF IBAT > IDETECT
Hi-Z IF IBAT < IDETECT
CHARGE TIME
ELAPSES
1/4 CHARGE TIME
ELAPSES
BAT < 4.1V
4063 F03
TRICKLE CHARGE MODE
1/10 FULL CURRENT
BAT > 2.9V
BAT < 2.9V
2.9V < BAT < 4.1V
BAT > 4.1V
CHGEN = 5V
OR
UVLO CONDITION
STANDBY MODE
NO CHARGE CURRENT
CHRG STATE: Hi-Z
SHUTDOWN MODE
ICC DROPS TO 35µA
CHRG STATE: Hi-Z
CHRG STATE: PULL-DOWN
FAULT MODE
NO CHARGE CURRENT
CHRG STATE: SQUARE WAVE
RECHARGE MODE
FULL CURRENT
CHRG STATE:
PULL-DOWN IF IBAT > IDETECT
Hi-Z IF IBAT < IDETECT
1/2 CHARGE
TIME ELAPSES
POWER ON
CHGEN = 0V
OR UVLO
CONDITION
STOPS
Figure 3. State Diagram of a Charge Cycle Using Charge Time Termination
LTC4063
13
4063fc
applicaTions inForMaTion
Charge Current Termination
Connecting the TIMER pin to ground selects Charge Cur-
rent Termination. With this method, the timer is disabled
and a resistor (RDET) must be connected from the IDET
pin to ground. IDETECT is programmed using the same
equation stated in the previous section (repeated here
for convenience):
IR
RIV
R
or
RV
I
DETECT PROG
DET CHG DET
DET DE
= =
=
10
100
100
•
TTECT
The charge cycle terminates when the charge current falls
below IDETECT
. This condition is detected using an internal,
filtered comparator to monitor the IDET pin. When the
IDET pin falls below 100mV for longer than tTERM (typically
1.5ms), charging is terminated.
When charging, transient loads on the BAT pin can cause
the IDET pin to fall below 100mV for short periods of
time before the DC current has dropped below the IDETECT
threshold. The 1.5ms filter time (tTERM) on the internal
comparator ensures that transient loads of this nature do
not result in premature charge cycle termination. Once the
average charge current drops below IDETECT
, the charger
terminates the charge cycle.
The CHRG output is in its pull-down state when charging
and in its high impedance state once charging has stopped.
Figure 4 describes the operation of the LTC4063 charger
when charge current termination is used.
User-Selectable Charge Termination
Connecting the TIMER pin to VCC selects User-Select-
able Charge Termination, in which all internal termination
features are disabled. The charge cycle continues indefi-
nitely until the charger is shut down through the CHGEN
pin. The IDET pin programs the behavior of the CHRG
output in the same manner as when using Charge Time
Termination. Specifically, when the charge current (IBAT)
is greater than IDETECT
, the CHRG output is in its pull-down
state. When the charger enters constant-voltage mode
operation and the charge current falls below IDETECT
, the
CHRG output becomes high impedance, indicating that
the battery is charged. If the IDET pin is not connected,
the CHRG output remains in its pull-down state until the
charger is shut down.
CHARGE MODE
FULL CURRENT
IBAT < IDETECT
IN VOLTAGE MODE
4063 F04
TRICKLE CHARGE MODE
1/10 FULL CURRENT
BAT > 2.9V
BAT < 2.9V
2.9V < BAT < 4.1V
BAT > 4.1V
BAT < 4.1V
CHGEN = 5V
OR
UVLO CONDITION
STANDBY MODE
NO CHARGE CURRENT
CHRG STATE: Hi-Z
SHUTDOWN MODE
ICC DROPS TO 35µA
CHRG STATE: Hi-Z
CHRG STATE: PULL-DOWN
CHRG STATE: PULL-DOWN
POWER ON
CHGEN = 0V
OR UVLO
CONDITION
STOPS
Figure 4. State Diagram of a Charge Cycle Using Charge Current Termination
LTC4063
14
4063fc
applicaTions inForMaTion
Figure 5. State Diagram of a Charger Cycle Using User Termination
Figure 6. Two Circuits that Charge at 500mA
Full-Scale Current and Terminate at 50mA
CHARGE MODE
FULL CURRENT
4063 F05
TRICKLE CHARGE MODE
1/10 FULL CURRENT
BAT > 2.9V
BAT < 2.9V
2.9V < BAT CHGEN = 5V
OR
UVLO CONDITION
SHUTDOWN MODE
ICC DROPS TO 35µA
CHRG STATE: Hi-Z
CHRG STATE: PULL-DOWN
POWER ON CHGEN = 0V
OR UVLO
CONDITION
STOPS
CHRG STATE:
PULL-DOWN IF IBAT > IDETECT
Hi-Z IF IBAT < IDETECT
With User-Selectable Charge Termination, the SmartStart
feature is disabled; when the charger is powered on or
enabled, the LTC4063 automatically begins charging, re-
gardless of the battery voltage. Figure 5 describes charger
operation when User-Selectable Charge Termination is
used.
Programming C/10 Current Detection/Termination
In most cases, an external resistor, RDET, is needed to set
the charge current detection threshold, IDETECT
. However,
when setting IDETECT to be 1/10th of ICHG, the IDET pin
can be connected directly to the PROG pin. This reduces
the component count, as shown in Figure 6.
When PROG and IDET are connected in this way, the
full-scale charge current, ICHG, is programmed using a
different equation:
RV
IIV
R
PROG CHG CHG PROG
= =
500 500
,
Stability Considerations
The battery charger constant voltage mode feedback loop
is stable without any compensation provided a battery
is connected. However, a 1µF capacitor with a 1Ω series
resistor to GND is recommended at the BAT pin to keep
ripple voltage low when the battery is disconnected.
When the charger is in constant current mode, the PROG
pin is in the feedback loop, not the battery. The constant
current stability is affected by the impedance at the PROG
pin. With no additional capacitance on the PROG pin, the
charger is stable with program resistor values as high as
10k; however, additional capacitance on this node reduces
the maximum allowed program resistor.
For the LDO regulator, a capacitor (COUT ) must be connected
from OUT to GND to ensure regulator loop stability. It is
recommended that low ESR capacitors be used for COUT
to reduce noise on the output of the linear regulator. COUT
must be ≥2µF for best performance.
+
VCC
PROG
IDET
VIN BAT 500mA
TIMER
RDET
2k
RPROG
2k
LTC4063
GND
+
VCC
PROG
IDET
VIN
4063 F06
BAT 500mA
TIMER
RPROG
1k
LTC4063
GND
LTC4063
15
4063fc
applicaTions inForMaTion
Regulator Output Noise
Noise measurements on the output should be made with
care to ensure accurate results. Coaxial connections and
proper shielding should be used to maintain measurement
integrity. Figure 7 shows a test setup for taking the mea-
surement. When the output is set to 3V and a 100mA load
is applied, the LTC4063 output noise power in the 10Hz to
100kHz band is typically measured to be 135µVRMS. For
more information on obtaining accurate noise measure-
ments for LDOs, see Application Note 83.
Power Dissipation
When designing the battery charger circuit, it is not
necessary to design for worst-case power dissipation
scenarios because the LTC4063 automatically reduces
the charge current during high power conditions. The
conditions that cause the LTC4063 to reduce charge cur-
rent through thermal feedback can be approximated by
considering the power dissipated in the IC. Most of the
power dissipation is generated from the internal charger
MOSFET (the LDO generates considerably less heat in most
applications). Thus, the power dissipation is calculated to
be approximately:
PD = (VCC – VBAT) • IBAT
PD is the power dissipated, VCC is the input supply voltage,
VBAT is the battery voltage and IBAT is the charge current.
The approximate ambient temperature at which the thermal
feedback begins to protect the IC is:
TA = 105°C – PD • θJA
TA = 105°C – (VCC – VBAT) • IBAT • θJA
Example: An LTC4063 operating from a 5V wall adapter
is programmed to supply 800mA full-scale current to a
discharged Li-Ion battery with a voltage of 3.3V. Assuming
θJA is 40°C/W (see Thermal Considerations), the ambient
temperature at which the LTC4063 will begin to reduce the
charge current is approximately:
TA = 105°C – (5V – 3.3V) • (800mA) • 40°C/W
TA = 105°C – 1.36W • 40°C/W = 105°C – 54.4°C
TA = 50.6°C
The LTC4063 can be used above 50.6°C ambient, but
the charge current will be reduced from 800mA. The ap-
proximate current at a given ambient temperature can be
approximated by:
IC T
V V
BAT A
CC BAT JA
=°
( )
105 –
– • θ
Using the previous example with an ambient temperature
of 60°C, the charge current will be reduced to approxi-
mately:
IC C
V V C W
C
C A
I
BAT
BAT
=° °
( )
°=°
°
=
105 60
5 3 3 40
45
68
–
– . • / /
6662mA
It is important to remember that LTC4063 applications
do not need to be designed for worst-case thermal
conditions, since the IC will automatically reduce power
dissipation when the junction temperature reaches ap-
proximately 105°C.
5Hz SINGLE ORDER
HIGHPASS
IN 10Hz TO 100kHz
4063 F07
GAIN = 60dB
10Hz 2nd ORDER
BUTTERWORTH HP
100kHz 4th ORDER
BUTTERWORTH LP
5Hz SINGLE ORDER
HIGHPASS
Figure 7. Filter Structure for Noise Testing LDOs
LTC4063
16
4063fc
Protection Features
While the thermally regulated charger limits the junction
temperature to 105°C during normal operation, current
overload at the LDO regulator output may result in exces-
sive power dissipation. Internal circuitry limits the output
currents, allowing the battery charger and regulator to
be short-circuited to ground indefinitely. Furthermore, if
the junction temperature exceeds 150°C, both the bat-
tery charger and regulator will shut down. The LTC4063
becomes enabled again once the junction temperature
drops below 140°C. If the fault condition remains in
place, the part will thermal cycle between the shutdown
and enabled states.
The LTC4063 also protects against reverse conduction
from the LDO output to the battery input. This provides
protection if a discharged (low voltage) battery is powering
the LDO, and the output voltage is held above the battery
voltage by a backup battery or a second regulator circuit.
When the output voltage is higher than the battery voltage,
the reverse output current is typically less than 50µA.
Thermal Considerations
In order to deliver maximum charge current under all
conditions, it is critical that the exposed metal pad on the
backside of the LTC4063 package is properly soldered to
the PC board ground. Correctly soldered to a 2500mm2
double sided 1oz copper board, the LTC4063 has a ther-
mal resistance of approximately 40°C/W. Failure to make
thermal contact between the exposed pad on the backside
of the package and the copper board will result in thermal
resistances far greater than 40°C/W. As an example, a
correctly soldered LTC4063 can deliver over 800mA to a
applicaTions inForMaTion
battery from a 5V supply at room temperature. Without
a good backside thermal connection this number would
drop to much less than 500mA.
VCC Bypass Capacitor
Many types of capacitors can be used for input bypassing,
however, caution must be exercised when using multilayer
ceramic capacitors. Because of the self-resonant and high
Q characteristics of some types of ceramic capacitors, high
voltage transients can be generated under some start-up
conditions such as connecting the charger input to a live
power source. Adding a 1.5Ω resistor in series with an X5R
ceramic capacitor will minimize start-up voltage transients.
For more information, see Application Note 88.
Charge Current Soft-Start and Soft-Stop
The LTC4063 includes a soft-start circuit to minimize the
inrush current at the start of a charge cycle. When a charge
cycle is initiated, the charge current ramps from zero to the
full-scale current over a period of approximately 100µs.
Likewise, internal circuitry slowly ramps the charge cur-
rent from full-scale to zero when the charger is shut down
or self terminates. This has the effect of minimizing the
transient current load on the power supply during start-up
and charge termination.
Reverse Polarity Input Voltage Protection
In some applications, protection from reverse polarity volt-
age on VCC is desired. If the supply voltage is high enough,
a series blocking diode can be used. In other cases where
the voltage drop must be kept low, a P-channel MOSFET
can be used (as shown in Figure 8).
VCC
VIN
4063 F08
LTC4063
DRAIN-BULK
DIODE OF FET
Figure 8. Low Loss Input Reverse Polarity Protection
LTC4063
17
4063fc
applicaTions inForMaTion
USB and Wall Adapter Power
The LTC4063 allows charging from both a wall adapter
and a USB port. Figure 9 shows how to combine wall
adapter and USB power inputs. A P-channel MOSFET,
MP1, is used to prevent back conducting into the USB
port when a wall adapter is present and a Schottky diode,
D1, is used to prevent USB power loss through the 1k
pull-down resistor.
Most wall adapters can supply more current than the 500mA
limited USB port. Therefore, an N-channel MOSFET, MN1,
and an extra 3.3k program resistor are used to increase
the charge current to 800mA when the wall adapter is
present.
+
VCC
D1
PROG
IDETGND
3.3k
2k
MN1
5V WALL
ADAPTER
ICHG = 800mA
USB POWER
ICHG = 500mA MP1
4063 F09
BAT
LTC4063
1.25k
Li-Ion
BATTERY
SYSTEM
LOAD
1k
Figure 9. Combining Wall Adapter and USB Power
Typical applicaTion
Full-Featured Li-Ion Charger with 2.5V Regulated Output
(Using Charge Time Termination)
+
CHRG
TIMER
PROG
IDET
6
7
9
8
BAT
OUT
FB
1
2
3
LTC4063
GND
340k
800mA
160k
11
625Ω
1.25k
1k 10
2.2µF
1µF
0.1µF
VIN
5V
4063 TA02
VOUT
2.5V
SINGLE CELL
Li-Ion BATTERY
VCC
LTC4063
18
4063fc
package DescripTion
DD Package
10-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1699 Rev C)
3.00 p0.10
(4 SIDES)
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2).
CHECK THE LTC WEBSITE DATA SHEET FOR CURRENT STATUS OF VARIATION ASSIGNMENT
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
TOP AND BOTTOM OF PACKAGE
0.40 p 0.10
BOTTOM VIEW—EXPOSED PAD
1.65 p 0.10
(2 SIDES)
0.75 p0.05
R = 0.125
TYP
2.38 p0.10
(2 SIDES)
15
106
PIN 1
TOP MARK
(SEE NOTE 6)
0.200 REF
0.00 – 0.05
(DD) DFN REV C 0310
0.25 p 0.05
2.38 p0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
1.65 p0.05
(2 SIDES)2.15 p0.05
0.50
BSC
0.70 p0.05
3.55 p0.05
PACKAGE
OUTLINE
0.25 p 0.05
0.50 BSC
PIN 1 NOTCH
R = 0.20 OR
0.35 s 45o
CHAMFER
LTC4063
19
4063fc
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
revision hisTory
REV DATE DESCRIPTION PAGE NUMBER
C 7/10 Updated Charge Time Termination equation 11
(Revision history begins at Rev C)
LTC4063
20
4063fc
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com
LINEAR TECHNOLOGY CORPORATION 2004
LT 0710 REV C • PRINTED IN USA
relaTeD parTs
PART NUMBER DESCRIPTION COMMENTS
Battery Chargers
LTC1733 Monolithic Lithium-Ion Linear Battery Charger Standalone Charger with Programmable Timer, Up to 1.5A Charge Current
LTC1734 Lithium-Ion Linear Battery Charger in ThinSOT™ Simple ThinSOT Charger, No Blocking Diode, No Sense Resistor Needed
LTC1734L Lithium-Ion Linear Battery Charger in ThinSOT Low Current Version of LTC1734, 50mA ≤ ICHRG ≤ 180mA
LTC4002 Switch Mode Lithium-Ion Battery Charger Standalone, 4.7V ≤ VIN ≤ 24V, 500kHz Frequency, 3 Hour Charge Termination
LTC4050 Lithium-Ion Linear Battery Charger Controller Features Preset Voltages, C/10 Charger Detection and Programmable Timer,
Input Power Good Indication, Thermistor Interface
LTC4052 Monolithic Lithium-Ion Battery Pulse Charger No Blocking Diode or External Power FET Required, ≤1.5A Charge Current
LTC4053 USB Compatible Monolithic Li-Ion Battery Charger Standalone Charger with Programmable Timer, Up to 1.25A Charge Current
LTC4054 Standalone Linear Li-Ion Battery Charger
with Integrated Pass Transistor in ThinSOT
Thermal Regulation Prevents Overheating, C/10 Termination,
C/10 Indicator, Up to 800mA Charge Current
LTC4057 Lithium-Ion Linear Battery Charger Up to 800mA Charge Current, Thermal Regulation, ThinSOT Package
LTC4058 Standalone 950mA Lithium-Ion Charger in DFN C/10 Charge Termination, Battery Kelvin Sensing, ±7% Charge Accuracy
LTC4059 900mA Linear Lithium-Ion Battery Charger 2mm × 2mm DFN Package, Thermal Regulation, Charge Current
Monitor Output
LTC4060 NiMH/NiCd Standalone Battery Charger 1-/4-Cell Series Batteries, No Microcontroller, No Firmware Required,
Termination by –dV, Max Voltage or Max Time, Up to 2A Charge Current
LTC4411/LTC4412 Low Loss PowerPath™ Controller in ThinSOT Automatic Switching Between DC Sources, Load Sharing,
Replaces ORing Diodes
Power Management
LTC3405/LTC3405A 300mA (IOUT), 1.5MHz, Synchronous Step-Down
DC/DC Converter
95% Efficiency, VIN: 2.7V to 6V, VOUT = 0.8V, IQ = 20µA, ISD < 1µA,
ThinSOT Package
LTC3406/LTC3406A 600mA (IOUT), 1.5MHz, Synchronous Step-Down
DC/DC Converter
95% Efficiency, VIN: 2.5V to 5.5V, VOUT = 0.6V, IQ = 20µA, ISD < 1µA,
ThinSOT Package
LTC3411 1.25A (IOUT), 4MHz, Synchronous Step-Down DC/DC
Converter
95% Efficiency, VIN: 2.5V to 5.5V, VOUT = 0.8V, IQ = 60µA, ISD < 1µA,
MS Package
LTC3440 600mA (IOUT), 2MHz, Synchronous Buck-Boost
DC/DC Converter
95% Efficiency, VIN: 2.5V to 5.5V, VOUT = 2.5V, IQ = 25µA, ISD < 1µA,
MS Package
USB/Wall Adapter Power Li-Ion Charger (Using Charge Current Termination)
+
VCC
TIMER
BAT
PROG
IDET
LTC4063
GND 2k
1µF
1k 11
8
9
110
7
10k
2.5k
µC
5V
WALL ADAPTER
USB
POWER
4063 TA03
Li-Ion
CELL
100mA/
500mA
Typical applicaTion