battery charger controller. It uses a synchronous quasi-
constant frequency PWM control architecture that will
not generate audible noise with ceramic bulk capacitors.
Charge current is set by the combination of external
sense, input and programming resistors. With no built-in
termination, the LTC4009 family charges a wide range of
batteries under external control.
The LTC4009 features a fully adjustable output voltage, while
the LTC4009-1 and LTC4009-2 can be pin-programmed for
lithium-ion/polymer battery packs of 1-, 2-, 3- or 4-series
cells. The LTC4009-1 provides output voltage of 4.1V/cell,
and the LTC4009-2 is a 4.2V/cell version.
The device includes AC adapter input current limiting which
maximizes the charge rate for a fixed input power level. An
external sense resistor programs the input current limit, and
the
ICL
status pin indicates when the battery charge current
is being reduced as a result of AC adapter current limiting.
The
CHRG
status pin is active during all charging modes,
including special indication for low charge current.
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General Purpose Battery Charger Controller
Efficient 550kHz Synchronous Buck PWM Topology
±0.5% Output Float Voltage Accuracy
Programmable Charge Current: 4% Accuracy
Programmable AC Adapter Current Limit:
3% Accuracy
No Audible Noise with Ceramic Capacitors
Wide Input Voltage Range: 6V to 28V
Wide Output Voltage Range: 2V to 28V
Indicator Outputs for AC Adapter Present, Charging,
C/10 Current Detection and Input Current Limiting
Analog Charge Current Monitor
Micropower Shutdown
Thermally Enhanced 20-Pin 4mm
×
4mm
×
0.75mm
QFN Package
applicaTions
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Notebook Computers
Portable Instruments
Battery Backup Systems
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners. Protected by U.S. Patents including 5723970.
Typical applicaTion
FROM
ADAPTER
13V TO 20V
33m
0.1µF
DCIN
14.3k
1.5k
CLP
0.1µF
5.1k
100
20µF
POWER TO
SYSTEM
Efficiency at DCIN = 20V
10000
95
EFFICIENCY (%)
90
85
80
75
70
POWER LOSS
V
OUT
= 12.3V
R
SENSE
= 33m
R
IN
= 3.01k
R
PROG
= 26.7k
D
IN
= SSB44
L = IHLP-2525CZ 6.8µH
0
0.5
1.0
1.5
2.0
CHARGE CURRENT (A)
2.5
1000
CLN
DCDIV BOOST
LTC4009
TGATE
CHRG
SW
INTV
DD
BGATE
GND
CSP
0.1µF
EFFICIENCY
POWER LOSS (mW)
TO/FROM
MCU
ACP
ICL
SHDN
ITH
6.04k
0.1µF
2µF
6.8µH
3.01k
33m
CSN
BAT
PROG
FBDIV
301k
V
FB
32.8k
3.01k
CHARGE
CURRENT
MONITOR
20µF
+
100
3.0
4.7nF
26.7k
12.3V
Li-Ion
BATTERY
4009 TA01a
4009 TA01b
4009fd
LTC4009
LTC4009-1/LTC4009-2
absoluTe MaxiMuM raTings
(Note 1)
DCIN, CLP, CLN or SW to GND................... –0.3V to 30V
CLP to CLN ............................................................±0.3V
CSP, CSN or BAT to GND ........................... –0.3V to 28V
CSP to CSN ............................................................±0.3V
BOOST to GND ........................................... –0.3V to 36V
BOOST to SW............................................... –0.3V to 7V
DCDIV,
SHDN,
FVS0, FVS1 or V
FB
to GND ... –0.3V to 7V
ACP, CHRG
or
ICL
to GND .......................... –0.3V to 30V
Operating Temperature Range
(Note 2) ............................................. –40°C to 125°C
Junction Temperature (Note 3) ............................. 125°C
Storage Temperature Range .................. –65°C to 150°C
pin conFiguraTion
LTC4009
TOP VIEW
INTV
DD
BOOST
BGATE
TGATE
SW
LTC4009-1
LTC4009-2
BOOST
TOP VIEW
INTV
DD
BGATE
15 CSP
14 CSN
21
13 PROG
12 ITH
11 BAT
6
SHDN
7
ACP
8
CHRG
9 10
FVS0
FVS1
TGATE
SW
20 19 18 17 16
CLN 1
CLP 2
DCIN 3
ICL
4
DCDIV 5
6
SHDN
7
ACP
8
CHRG
9 10
FBDIV
V
FB
21
15 CSP
14 CSN
13 PROG
12 ITH
11 BAT
CLN 1
CLP 2
DCIN 3
ICL
4
DCDIV 5
20 19 18 17 16
UF PACKAGE
20-LEAD (4mm 4mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 37°C/W
EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB
UF PACKAGE
20-LEAD (4mm 4mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 37°C/W
EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LTC4009CUF#PBF
LTC4009CUF-1#PBF
LTC4009CUF-2#PBF
LTC4009IUF#PBF
LTC4009IUF-1#PBF
LTC4009IUF-2#PBF
TAPE AND REEL
LTC4009CUF#TRPBF
LTC4009CUF-1#TRPBF
LTC4009CUF-2#TRPBF
LTC4009IUF#TRPBF
LTC4009IUF-1#TRPBF
LTC4009IUF-2#TRPBF
PART MARKING*
4009
40091
40092
4009
40091
40092
PACKAGE DESCRIPTION
20-Lead (4mm
×
4mm) Plastic QFN
20-Lead (4mm
×
4mm) Plastic QFN
20-Lead (4mm
×
4mm) Plastic QFN
20-Lead (4mm
×
4mm) Plastic QFN
20-Lead (4mm
×
4mm) Plastic QFN
20-Lead (4mm
×
4mm) Plastic QFN
TEMPERATURE RANGE
0°C to 85°C
0°C to 85°C
0°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
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/
4009fd
LTC4009
LTC4009-1/LTC4009-2
elecTrical characTerisTics
SYMBOL
V
TOL
PARAMETER
V
BAT
Accuracy (See Test Circuits)
Charge Voltage Regulation
LTC4009
C-Grade
I-Grade
LTC4009-1/LTC4009-2
C-Grade
FVS1 = 0V, FVS0 = 0V, I-Grade
FVS1 = 0V, FVS1 = 5V, I-Grade
FVS1 = 5V, FVS0 = 0V, I-Grade
FVS1 = 5V, FVS1 = 5V, I-Grade
I
VFB
R
ON
I
LEAK-FBDIV
V
BOV
V
FB
Input Bias Current
FBDIV On-Resistance
FBDIV Output Leakage Current
V
FB
Overvoltage Threshold
BAT Overvoltage Threshold
Charge Current Regulation
I
TOL
Charge Current Accuracy with R
IN
= 3.01k,
6V < BAT < 18V (LTC4009),
6V < BAT < 15V (LTC4009-1, LTC4009-2)
Current Sense Amplifier Gain (PROG
∆I)
with
R
IN
= 3.01k, 6V < BAT < 18V (LTC4009),
6V < BAT < 15V (LTC4009-1, LTC4009-2)
R
PROG
= 26.7k
C-Grade
I-Grade
V
SENSE
= 0mV, PROG = 1.2V
A
I
V
CS-MAX
V
C10
V
REV
V
CL
I
CLN
V
ICL
OVR
I
DCO
I
CLPO
V
CBT
V
CNT
V
OVP
Shutdown
V
ACP
V
ACP(HYST)
I
DCDIV
V
IL
DCDIV AC Present Threshold Voltage
DCDIV ACP Threshold Hysteresis Voltage
DCDIV Input Current
SHDN
Input Voltage Low
DCDIV = 1.2V
l
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l
l
l
l
l
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T