FEATURES
■
■
■
LTC4059/LTC4059A
900mA Linear Li-Ion
Battery Chargers with
Thermal Regulation in 2
×
2 DFN
DESCRIPTIO
The LTC
®
4059/LTC4059A are constant-current/constant-
voltage linear chargers for single cell lithium-ion batteries.
Their 2mm
×
2mm DFN package and low external compo-
nent count make these chargers especially well suited for
portable applications. Furthermore, they are designed to
work within USB power specifications.
No external sense resistor, MOSFET or blocking diode is
required. Thermal feedback regulates the charge current
to limit the die temperature during high power operation or
high ambient thermal conditions. The charge voltage is
fixed at 4.2V and the charge current is programmable.
When the input supply (wall adapter or USB supply) is
removed, the LTC4059/LTC4059A automatically enter a low
current state, dropping the battery current drain to less than
1µA. With power applied, they can be put into shutdown
mode, reducing the supply current to 10µA.
The LTC4059A features an open-drain status pin to indi-
cate the presence of an input voltage. The LTC4059 can be
used as a constant-current source to charge Nickel cells.
Other features include undervoltage lockout protection
and a current monitor pin which can indicate when to
terminate a charge cycle.
The LTC4059/LTC4059A are available in a 6-lead, low
profile (0.75mm) 2mm
×
2mm DFN package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 6522118.
■
■
■
■
■
■
■
■
Programmable Charge Current Up to 900mA
Charge Current Monitor Output for Charge
Termination
Constant-Current/Constant-Voltage Operation with
Thermal Regulation to Maximize Charging Rate
Without Risk of Overheating
Constant-Current Source Mode for Charging
Nickel Batteries (LTC4059 Only)
ACPR Pin Indicates Presence of Input Supply
(LTC4059A Only)
No External MOSFET, Sense Resistor or Blocking
Diode Required
Operating Supply Voltage from 3.75V to 8V
Charges Single Cell Li-Ion Batteries Directly from
USB Port
Preset 4.2V Charge Voltage with 0.6% Accuracy
10µA Supply Current in Shutdown Mode
Tiny 6-Lead (2mm
×
2mm) DFN Package
APPLICATIO S
■
■
■
■
■
Wireless PDAs
Cellular Phones
Portable Electronics
Wireless Headsets
Digital Cameras
TYPICAL APPLICATIO
V
IN
4.5V TO 8V
V
CC
1µF
EN
GND
ACPR
Complete Charge Cycle (800mAh Battery)
700
V
DD
CHARGE CURRENT (mA)
600
500
400
300
200
100
0
0
CONSTANT
CURRENT
50k
µP
600mA
LTC4059A
BAT
PROG
2k
+
4.2V
Li-Ion
BATTERY
4059 TA01
V
CC
= 5V
R
PROG
= 2k
T
A
= 25°C
0.5
1
1.5
2
TIME (HOURS)
U
U
U
CONSTANT
VOLTAGE
4.4
4.2
BATTERY VOLTAGE (V)
4.0
3.8
3.6
3.4
3.2
3.0
2.5
4059 TA02
4059fb
1
LTC4059/LTC4059A
ABSOLUTE
(Note 1)
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
GND 1
Li CC/ACPR* 2
BAT 3
7
6 EN
5 PROG
4 V
CC
Input Supply Voltage (V
CC
) ...................... –0.3V to 10V
BAT, PROG, EN, Li CC, ACPR ................... –0.3V to 10V
BAT Short-Circuit Duration ........................... Continuous
BAT Pin Current ............................................... 1000mA
PROG Pin Current ............................................. 1000µA
Junction Temperature .......................................... 125°C
Operating Temperature Range (Note 2) .. – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 125°C
ORDER PART
NUMBER
LTC4059EDC
LTC4059AEDC
DC6 PART
MARKING
LAFU
LBJH
DC6 PACKAGE
6-LEAD (2mm
×
2mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 60°C/W TO 85°C/W (NOTE 3)
*Li CC PIN 2 ON LTC4059EDC,
ACPR PIN 2 ON LTC4059AEDC
EXPOSED PAD (PIN 7) IS GND
MUST BE SOLDERED TO PCB
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V unless otherwise noted.
SYMBOL
V
CC
I
CC
I
CCMS
I
CCUV
V
FLOAT
I
BAT
I
BMS
I
BUV
V
UV
V
PROG
V
MS
V
MSHYS
R
EN
V
Li CC
V
Li CCHYS
V
ACPR
t
LIM
R
ON
PARAMETER
V
CC
Supply Voltage
Quiescent V
CC
Supply Current
V
CC
Supply Current in Shutdown
V
CC
Supply Current in Undervoltage
Lockout
V
BAT
Regulated Output Voltage
BAT Pin Current
Battery Drain Current in Shutdown
Battery Drain Current in Undervoltage
Lockout
V
CC
– V
BAT
Undervoltage Lockout
Threshold
PROG Pin Voltage
Manual Shutdown Threshold
Manual Shutdown Hysteresis
EN Pin Input Resistance
Voltage Mode Disable Threshold
Voltage Mode Disable Hysteresis
ACPR Pin Output Low Voltage
Junction Temperature In Constant
Temperature Mode
Power FET “ON” Resistance
(Between V
CC
and BAT)
CONDITIONS
●
ELECTRICAL CHARACTERISTICS
MIN
3.75
TYP
25
10
4
V
BAT
= 4.5V (Forces I
BAT
and I
PROG
= 0)
V
EN
= V
CC
V
CC
< V
BAT
; V
CC
= 3.5V, V
BAT
= 4V
I
BAT
= 2mA
4.5V < V
CC
< 8V, I
BAT
= 2mA
R
PROG
= 2.43k, Current Mode, V
BAT
= 3.8V
R
PROG
= 12.1k, Current Mode, V
BAT
= 3.8V
V
EN
= V
CC
, V
CC
> V
BAT
V
CC
< V
BAT
, V
BAT
= 4V
V
CC
from Low to High, V
BAT
= 3.7V
V
CC
from High to Low, V
BAT
= 3.7V
R
PROG
= 2.43k, I
PROG
= 500µA
R
PROG
= 12.1k, I
PROG
= 100µA
V
EN
Increasing
V
EN
Decreasing
V
EN
= 5V
V
Li CC
Increasing (LTC4059 Only)
V
Li CC
Decreasing (LTC4059 Only)
I
ACPR
= 300µA (LTC4059A Only)
●
●
●
MAX
8
60
25
10
4.225
4.242
525
106
±1
4
200
80
1.24
1.24
1.2
3
1.2
0.5
UNITS
V
µA
µA
µA
V
V
mA
mA
µA
µA
mV
mV
V
V
V
mV
MΩ
V
mV
V
°C
mΩ
●
●
●
●
●
●
●
●
●
●
●
●
4.175
4.158
475
94
0
100
0
1.18
1.18
0.3
1
0.3
4.2
4.2
500
100
0
1
150
35
1.21
1.21
0.92
85
1.85
0.92
85
0.25
115
800
I
BAT
= 150mA (Note 4)
1200
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
The LTC4059E/LTC4059AE are 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 solder the exposed backside of the package to the PC
board ground plane will result in a thermal resistance much higher than
60°C/W.
Note 4:
The FET on-resistance is guaranteed by correlation to wafer level
measurements.
4059fb
2
U
W
U
U
W W
W
LTC4059/LTC4059A
TYPICAL PERFOR A CE CHARACTERISTICS
Battery Regulation (Float) Voltage
vs Battery Charge Current
4.26
4.24
4.22
V
CC
= 5V
T
A
= 25°C
R
PROG
= 2.43k
4.24
4.23
4.22
V
FLOAT
(V)
V
FLOAT
(V)
4.18
4.16
4.14
4.12
4.10
0
100
200
300
I
BAT
(mA)
400
500
4059 G01
4.20
4.19
4.18
4.17
4.16
–50
–25
50
25
TEMPERATURE (°C)
0
75
100
4059 G02
V
FLOAT
(V)
4.20
Charge Current vs Input Voltage
600
500
R
PROG
= 2.43k
400
THERMAL
LIMITING
V
BAT
= 3.85V
T
A
= 25°C
600
I
BAT
(mA)
I
BAT
(mA)
300
200
100
0
4
5
6
V
CC
(V)
4059 G04
300
200
I
BAT
(mA)
R
PROG
= 12.1k
7
PROG Pin Voltage
vs Charge Current
1.4
1.2
1.0
V
PROG
(V)
V
PROG
(V)
V
CC
= 5V
T
A
= 25°C
R
PROG
= 2.43k
R
DS(ON)
(mΩ)
0.8
0.6
0.4
0.2
0
0
100
200
300
400
500
4059 F07
I
BAT
(mA)
U W
8
Battery Regulation (Float) Voltage
vs Temperature
V
CC
= 5V
I
BAT
= 2mA
R
PROG
= 2.43k
4.24
4.23
4.22
4.21
4.20
4.19
4.18
4.17
4.16
Regulated Output (Float) Voltage
vs Supply Voltage
T
A
= 25°C
I
BAT
= 10mA
R
PROG
= 2.43k
4.21
4
5
6
V
CC
(V)
7
8
4059 G03
Charge Current vs Battery Voltage
Li CC = 5V
LTC4059 ONLY
500
400
Li CC = 0V
LTC4059A
600
Charge Current vs Ambient
Temperature with Thermal
Regulation
R
PROG
= 2.43k
500
400
THERMAL CONTROL
LOOP IN OPERATION
300
200
100
0
V
CC
= 5V
T
A
= 25°C
R
PROG
= 2.43k
2.5
3
3.5
V
BAT
(V)
4
4.5
4059 G05
100
0
–50 –25
V
CC
= 5V
V
BAT
= 3.85V
R
PROG
= 12.1k
50
100
25
75
0
AMBIENT TEMPERATURE (°C)
125
4059 G06
PROG Pin Voltage vs Temperature
(Constant Current Mode)
1.24
1.23
1.22
R
PROG
= 12.1k
1.21
1.20
1.19
1.18
–50 –25
R
PROG
= 2.43k
V
CC
= 5V
V
BAT
= 3.85V
Power FET “ON” Resistance
vs Temperature
1200
1000
900
800
700
600
500
400
–50
V
CC
= 5V
I
BAT
= 100mA
50
25
75
0
TEMPERATURE (°C)
100
125
–25
0
25
50
TEMPERATURE (°C)
75
100
4059 G09
4059 G08
4059fb
3
LTC4059/LTC4059A
TYPICAL PERFOR A CE CHARACTERISTICS
V
CC
– V
BAT
Undervoltage Lockout
Threshold vs Battery Voltage
500
T
A
= 25°C
450 R
PROG
= 12.1k
400
350
2.5
3.5
3.0
T
A
= 25°C
V
UV
(mV)
250
200
150
100
50
0
3
4
6
5
V
BAT
(V)
7
8
4059 G10
EN (µA)
2.0
T
A
= –20°C
1.5
1.0
0.5
0
0
1
2
3
V
EN
(V)
4059 G11
I
BUV
(µA)
6
300
UVLO Battery Drain Current
vs Temperature
2.5
V
CC
= 0V
V
BAT
= 4V
14
12
10
2.0
I
CCMS
(µA)
I
BUV
(µA)
V
MS
(V)
1.5
1.0
0.5
2
0
–50 –25
50
25
0
75
TEMPERATURE (°C)
ACPR Pin Output Low Voltage
vs Temperature (LTC4059A Only)
0.50
V
CC
= 5V
0.45 V
BAT
= 4.2V
I
ACPR
= 300µA
0.40
I
ACPR
(mA)
V
ACPR
(V)
0.30
0.25
0.20
0.15
0.10
– 50 – 25
0
50
75
25
TEMPERATURE (°C)
100
125
2.0
1.5
1.0
0.5
0
0
1
2
3
4
V
ACPR
(V)
5
6
7
8
V
Li CC
(V)
0.35
4
U W
100
4059 G13
4059 G17
EN Pin Current
vs EN Voltage and Temperature
2.0
UVLO Battery Drain Current
vs Battery Voltage
V
CC
= 0V
1.8 T
A
= 25°C
1.6
1.4
T
A
= 100°C
1.2
1.0
0.8
0.6
0.4
0.2
4
5
0
0
1
3
2
V
BAT
(V)
4
5
4059 G12
Manual Shutdown Supply Current
vs Temperature
V
CC
= 5V
V
EN
= 5V
Manual Shutdown Threshold
Voltage vs Temperature
1.2
1.1
1.0
RISING
0.9
FALLING
0.8
0.7
0.6
–50
8
6
4
125
0
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
125
–25
0
25
50
TEMPERATURE (°C)
75
100
4059 F15
4059 G14
ACPR Pin (Pull-Down State)
I-V Curve (LTC4059A Only)
4.0
3.5
3.0
2.5
V
CC
= 5V
V
BAT
= 4.2V
T
A
= 25°C
Voltage Mode Disable Threshold
Voltage vs Temperature
(LTC4059 Only)
1.2
1.1
1.0
RISING
0.9
0.8
0.7
0.6
–50
FALLING
–25
0
25
50
TEMPERATURE (°C)
75
100
4059 F16
4059 G18
4059fb
LTC4059/LTC4059A
PI FU CTIO S
GND (Pins 1, 7):
Ground/Exposed Pad. The exposed
package pad is ground and must be soldered to the PC
board for maximum heat transfer.
Li CC (Pin 2, LTC4059):
Li-Ion/Constant Current Input
Pin. Pulling this pin above V
Li CC
disables voltage mode
thereby providing a constant current to the BAT pin. This
feature is useful for charging Nickel chemistry batteries.
Tie to GND if unused.
ACPR (Pin 2, LTC4059A):
Open-Drain Power Supply
Status Output. When V
CC
is greater than the undervoltage
lockout threshold, the ACPR pin will pull to ground;
otherwise the pin is forced to a high impedance state.
BAT (Pin 3):
Charge Current Output. Provides charge
current to the battery and regulates the final float voltage
to 4.2V. An internal precision resistor divider from this pin
sets this float voltage and is disconnected in shutdown
mode.
V
CC
(Pin 4):
Positive Input Supply Voltage. This pin
provides power to the charger. V
CC
can range from 3.75V
to 8V. This pin should be bypassed with at least a 1µF
capacitor. When V
CC
is within 35mV of the BAT pin
voltage, the LTC4059 enters shutdown mode, dropping
I
BAT
to less than 4µA.
PROG (Pin 5):
Charge Current Program and Charge Cur-
rent Monitor Pin. Connecting a resistor, R
PROG
, to ground
programs the charge current. When charging in constant-
current mode, this pin servos to 1.21V. In all modes, the
voltage on this pin can be used to measure the charge
current using the following formula:
U
U
U
I
BAT
=
V
PROG
• 1000
R
PROG
EN (Pin 6):
Enable Input Pin. Pulling this pin above the
manual shutdown threshold (V
MS
is typically 0.92V) puts
the LTC4059 in shutdown mode, thus terminating a charge
cycle. In shutdown mode, the LTC4059 has less than 25µA
supply current and less than 1µA battery drain current.
Enable is the default state, but the pin should be tied to
GND if unused.
4059fb
5
京公网安备 11010802033920号
EEWORLD
