LTC4010
High Efficiency Standalone
Nickel Battery Charger
FeaTures
DescripTion
The LTC®4010 provides a complete, cost-effective nickel
battery fast charge solution in a small package using few
external components. A 550kHz PWM current source
controller and all necessary charge initiation, monitoring
and termination control circuitry are included.
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Complete NiMH/NiCd Charger for 1 to 16 Cells
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No Microcontroller or Firmware Required
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550kHz PWM Current Source Controller
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No Audible Noise with Ceramic Capacitors
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Wide Input Voltage Range: 5.5V to 34V
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Programmable Charge Current: 5% Accuracy
The LTC4010 automatically senses the presence of a DC
adapterandbatteryinsertionorremoval.Whenanexternal
DC source is not present, the LTC4010 enters shutdown
and supply current drawn from an installed battery drops
to the lowest possible level. Heavily discharged batteries
are precharged with a trickle current. The LTC4010 can
simultaneously use both –∆V and ∆T/∆t fast charge ter-
mination techniques and can detect various battery faults.
If necessary, a top-off charge is automatically applied to
NiMH batteries after fast charging is completed. The IC
will also resume charging if the battery self-discharges
after a full charge cycle.
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Automatic Trickle Precharge
–∆V Fast Charge Termination
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Optional ∆T/∆t Fast Charge Termination
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Optional Temperature Qualification
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Automatic NiMH Top-Off Charge
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Programmable Timer
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Automatic Recharge
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Multiple Status Outputs
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Micropower Shutdown
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16-Lead Thermally Enhanced TSSOP Package
applicaTions
All LTC4010 charging operations are qualified by actual
charge time and maximum average cell voltage. Charging
mayalsobegatedbyminimumandmaximumtemperature
limits. NiMH or NiCd fast charge termination parameters
are pin selectable.
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Integrated or Standalone Battery Charger
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Portable Instruments or Consumer Products
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Battery-Powered Diagnostics and Control
Back-Up Battery Management
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L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Typical applicaTion
2A NiMH Battery Charger
TO
SYSTEM
LOAD
FROM
ADAPTER
9V
2A NiMH Charge Cycle at 1C
10µF
3k
LTC4010
1.60
1.55
42
40
V
CC
FAULT
CHRG
READY
TGATE
1.50
38
BGATE
47µH
SINGLE CELL
VOLTAGE
TIMER PGND
1.45
1.40
1.35
1.30
36
34
32
30
49.9k
SENSE
GND
CHEM
BATTERY
TEMPERATURE
0.05Ω
BAT
2A
CHARGE
10µF
10k
CURRRENT
10k
1A
TOP OFF
V
V
CDIV
CELL
2-CELL
NiMH PACK
1.25
28
33nF
0
60
TIME (MINUTES)
80
100
20
40
WITH 10k NTC
V
INTV
TEMP
DD
4010 TA01b
0.1µF
68nF
4010 TA01a
4010fb
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