1
DEMO MANUAL DC086
BATTERY CHARGER
LT1510 Constant-Voltage/
Constant-Current Lithium-Ion
Battery Charger
DESCRIPTIO
U
Demonstration board DC086 is a complete lithium-ion
battery charger designed for 1-, 2- or 3-cell applications
(other rechargeable battery types can also be charged, see
page three). The LT
®
1510 is used in a high efficiency
current mode step-down switching topology, capable of
providing up to 1.5A of charging current. This demo board
uses all surface mount components, resulting in a circuit
occupying approximately 1 square inch of board area with
less than 0.3 in. (7.6mm) height.
Jumpers J1 and J2, located on the demo board, are used
to select the correct charging voltage for the number of
cells being charged (4.2V, 8.4V or 12.6V). Charging cur-
rent is programmed for 1.3A by resistor R1.
The DC input voltage must be at least 3V greater than the
output voltage. When the input voltage is removed, an
external low current MOSFET (Q1) provides a disconnect
for the output voltage divider resistors and the chip goes
into a sleep mode, draining approximately 3
µ
A from the
battery.
PARAMETER
CONDITIONS
LIMITS
V
IN
V
OUT
+ 3V
≤
V
IN
≤
28V*
Battery Voltage (V
BAT
)
V
IN
= 10V
4.2
±
0.7%
When Charging Terminates
V
IN
= 15V
8.4V
±
0.7%
V
IN
= 20V
12.6V
±
0.7%
Maximum Battery Charging Current
1.3A
±
5%
PERFOR A CE SU ARY
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W
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Charging Efficiency
BATTERY CHARGING CURRENT (A)
0.1
EFFICIENCY (%)
0.7
DM086 • TPC01
0.3
0.5
0.9
96
94
92
90
88
86
84
82
80
1.1
1.3
1.5
V
CC
= 15V
V
BAT
= 8.4V
Component Side Demo Board
Note: Good thermal PC board layout techniques are required when operating near maximum power levels to prevent excessive junction temperatures.
Note: For 0.5% battery-voltage accuracy, replace R3 to R8 with 0.1% resistors.
*For V
IN
> 25V, C1 should be replaced with a higher voltage rating capacitor.
TYPICAL PERFOR A CE CHARACTERISTICS A D BOARD PHOTO
U
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W
, LTC and LT are registered trademarks of Linear Technology Corporation.
