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dc2133afa

DEMO MANUAL DC2133A

DESCRIPTION

LTC4079

60V, 250mA Linear Charger

with Low Quiescent Current

Demonstration circuit 2133A features a simple battery

charger circuit using the LTC®4079 high-voltage mono-

lithic linear charger. The DC2133 has an input voltage

range from 2.7V to 60V and is capable of supplying up

to 250mA charge current. The charge voltage is jumper-

selectable to 4.2V or 8.4V. Charge current is adjustable

via the PROG pin and initially programmed for 99mA. In

shutdown or when unpowered, LTC4079 consumes only

10nA from the battery.

DC2133A is initially configured to enable charging from

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.

PERFORMANCE SUMMARY

The NTC input is connected to an on-board resistance to

enable charging with only a 2-wire battery connection;

however an external thermistor may be used with the

NTC test point.

Termination is accomplished by timer method. Charging

status is reflected by the CHRG LED.

Design files for this circuit board are available at

http://www.linear.com/demo/DC2133A

Figure 1. Typical Battery Charge Cycle

PARAMETER

CONDITIONS

TYPICAL VALUE

Input Voltage Range

2.7V to 60V

Default Charging Voltage

4.2V

Default Charging Current

99mA

PROG Pin Voltage

2.5V

Input Regulation Voltage

EN = REG (JP1)

10.3V

Default Charge Timer

3h 45 min

TIME (HOURS)

0

100

80

60

40

20

90

70

50

30

10

0

1

dc2133a F01

5

3

2

4

3.2

3.6

5.2

3.4

3.8

4.6

4.4

4.2

4

5.0

4.8

C/10

TERMINATION

CHRG

240mAh Li-Ion