QUICK START GUIDE FOR DEMONSTRATION CIRCUIT DC512B
4A SMART BATTERY CHARGER
1
LTC4100
DESCRIPTION
Demonstration circuit DC512B is a single battery switch-
ing step-down charge controller featuring the LTC4100.
The recommended input power is 15 to 20V at 3.5A. A
two-position jumper allows choice of protected output
voltage range suitable for 3- and 4-Cell Li-ion batteries.
Removal of the jumper allows full output voltage range.
The maximum charge current is 4A.
The demo board is initially configured for 12.6V at 3A
for popular 3-cell Li-ion battery packs. LTC4100 will au-
tomatically charge a Smart Battery to termination as
soon as input power is applied with a battery connected
prior to power up. A VOUT pin automatically provides
power to the system load from the wall adapter or bat-
tery. Status LEDs are provided for CHG, ACP,
SMBALERT
and SMBus activity.
The optional DC1223A-B SMBUS to USB adapter and
associated software to control, monitor, and data log the
system for demonstration purposes only. This software
is not required to charge a battery with the DC512B.
Contact your LT representative for ordering a
DC1223A-B.
Design files for this circuit board are available at
http://www.linear.com/demo
Performance Summary
T
A
= 25°C
PARAMETER CONDITIONS
/
NOTES
VALUE
Input Voltage Range
VIN > VBAT to charge. Limited by input capacitor ratings.
15 – 25V
ACP Trip voltage
V
DCDIV
Rising
14.6V ± 3%
Input Current Limit
3.5A ± 7%
Battery Voltage Limit
3CELL (R
VILIM
= 10kΩ ± 1%)
13.104VBAT, Typ.
4CELL (R
VILIM
= 33kΩ ± 1%)
17.408VBAT, Typ.
R
VILIM
OPEN
28.006, Typ.
Programmable Float Voltage Accuracy
± 0.8%
Minimum Voltage Step
All VLIM Settings
16mV
# of Voltage Steps
11-Bit range
2048 steps
Battery Current Sense Voltage Limit
3A (R
ILIM
= 33kΩ ± 1%)
82.3mV, Max
4A (R
ILIM
OPEN)
107.3mV, Max
Programmable Charge Current Accuracy
±5%, 3% is typical
Minimum Current Step
3A & 4A Settings
4mA
# of Current Steps
10-Bit range
1024 Steps
