LTC4096/LTC4096X

11

4096xf

TRICKLE CHARGE*

MODE

1/10th FULL CURRENT

CHRG STATE: PULLDOWN

PWR STATE: DCIN

SHUTDOWN

MODE

CHRG STATE: Hi-Z

PWR STATE: USBIN

CHARGE

MODE

FULL CURRENT

CHRG STATE: PULLDOWN

PWR STATE: DCIN

CHARGE

MODE

FULL CURRENT

CHRG STATE: PULLDOWN

PWR STATE: USBIN

STANDBY

MODE

NO CHARGE CURRENT

CHRG STATE: Hi-Z

PWR STATE: DCIN

SHUTDOWN

MODE

CHRG STATE: Hi-Z

PWR STATE: DCIN

BAT > 2.9V

BAT < 2.9V

BAT < 2.9V

2.9V < BAT

2.9V < BAT

BAT > 2.9V

BAT < 4.15V

BAT < 4.15V

IN VOLTAGE MODE

IN VOLTAGE MODE

POWER SELECTION

STANDBY

MODE

NO CHARGE CURRENT

CHRG STATE: Hi-Z

PWR STATE: USBIN

TRICKLE CHARGE*

MODE

1/10th FULL CURRENT

CHRG STATE: PULLDOWN

PWR STATE: USBIN

SUSP

DRIVEN HIGH

SUSP

DRIVEN LOW

*NOT PRESENT IN THE "X" VERSION

SUSP

DRIVEN HIGH

DCIN POWER

REMOVED

DCIN POWER

REMOVED

USBIN POWER

REMOVED OR

DCIN POWER

APPLIED

USBIN POWER

REMOVED OR

DCIN POWER

APPLIED

DCIN POWER APPLIED

ONLY USB POWER APPLIED

STARTUP

4096 F01

SUSP

DRIVEN LOW

Manual Shutdown

The SUSP pin has a 3.4M

Ω pulldown resistor to GND. A

logic low enables the charger and logic high disables it

(the pulldown defaults the charger to the charging state).

The DCIN input draws 20µA when the charger is in shut-

down. The USBIN input draws 20µA during shutdown if

no power is applied to DCIN, but draws only 10µA when

Thermal Limiting

An internal thermal feedback loop reduces the programmed

charge current if the die temperature attempts to rise

above a preset value of approximately 115°C. This feature

protects the LTC4096 from excessive temperature and

allows the user to push the limits of the power handling

capability of a given circuit board without risk of damag-

ing the device. The charge current can be set according

to typical (not worst case) ambient temperature with the

assurance that the charger will automatically reduce the

current in worst case conditions. A safety thermal shut

down circuit will turn off the charger if the die temperature

rises above a value of approximately 150°C. DFN power

considerations are discussed further in the Applications

Information section.

APPLICATIONS INFORMATION

Figure 1. LTC4096 State Diagram of a Charge Cycle