TWL2214CA
POWER SUPPLY MANAGEMENT IC AND
LiIon BATTERY CHARGE CONTROL
SLVS321A – OCTOBER 2001 – REVISED JANUARY 2002
28
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
APPLICATION INFORMATION
status register description—SR (1CH)
SR shows the status of the charger. The external controller reads the SR to track the state of the charging
condition.
BIT
NAME
DESCRIPTION
7
Vext
When Vext = 1, the VCHG input is in the operating range. Otherwise the VCHG is out of range.
6
BATERR
This bit is set to 1 indicating battery error. Four cases cause battery error: precharge timeout, constant-current mode
timeout, VBAT < 2.9 V, or VBAT > 4.45 V.
5
VBOT
During the charging cycle, if the battery temperature exceeds or falls below the nominal range, this sets to 1. The
charger is suspended temporarily. VBOT is cleared when the temperature returns to nominal range and the charger
function resumes automatically.
4
CTERM
The charger is terminated normally because the charging current is below the preset termination current value.
3
NOCHG
No charge condition. This condition is detected only during the wake-up state of the charging function. After the
8-second wake-up period expires, if VBAT is above 4.3 V, the NOCHG flag is set. The cause of this is a missing or
completely charged battery. The TWL2214CA device does not deactivate the charger by setting CHGSTR = 0. The
external processor must turn off the CHGSTR bit by setting it to 0.
2
PCHG
Set to 1 to indicate the charger is in precharge state.
1
CCTO
Set to 1 to indicate the charging time has exceeded the time limit allowed during CC mode. This is a fatal error. The
TWL2214CA device clears CHGSTR bit, sets the BATERR flag, and makes IRQ go high to interrupt the external
controller.
0
TCTO
Set to 1 to indicate the charging time has exceeded the overall time limit allowed during CV mode. This is treated
as normal termination of the charger function. The TWL2214CA device clears bit 7 (CHGSTR) of the control register
and sets IRQ to 1 to interrupt the external controller.