LTC4110
19
4110fb
• The SafetySignal is registering RES_OR. Charge is
stopped. The LTC4110 enters the reset state.
• The AC power is no longer present (DCDIV < V
AC
or
DCIN < UVLO). The LTC4110 enters the reset state.
• ALARM_INHIBITED is set in the ChargerStatus()
register. Charge is stopped. The LTC4110 enters the
SMBus OFF state.
• CHARGE_INHIBIT is set in the BBuControl() register.
Charge is stopped, however, the T/4 timer is not paused.
Clearing CHARGE_INHIBIT will enable the LTC4110 to
resume charge.
• RESET_TO_ZERO is set in the BBuControl() register.
Charge is stopped. The LTC4110 enters the SMBus
OFF state.
• Writing a zero value to ChargeVoltage() or ChargeCur-
rent() register. Charge is stopped. The LTC4110 enters
the SMBus OFF state.
•
If the battery voltage exceeds the bulk charge threshold,
the LTC4110 will enter the SMBus bulk charge state.
• If the T/4 timeout occurs, charge is stopped and the
LTC4110 enters the SMBus OFF state.
• The CAL_START bit in the BBuControl() register is
set. Charge is stopped and the LTC4110 enters the
calibration mode.
SMBus BULK CHARGE STATE
The charger will be operating in the bulk charge current
limit during the SMBus bulk charge state. The following
conditions must be met in order to allow SMBus bulk
charge to start:
• The ChargeVoltage() AND ChargeCurrent() registers
must be written to non-zero values. The LTC4110 will
not directly report the status of these registers.
• The SafetySignal must be RES_COLD, RES_IDEAL, or
RES_UR.
• AC must be present and suffi cient. This is qualifi ed by
DCDIV > V
AC
+ V
ACH
and DCIN > UVLO.
The following conditions will affect the SMBus bulk charge
state as specifi ed below:
OPERATION
• The ChargeCurrent() AND ChargeVoltage() registers
have not been written for t
TIMEOUT
. Charge is stopped
and the LTC4110 enters the SMBus OFF state.
• The SafetySignal is registering RES_OR. Charge is
stopped and the LTC4110 enters the reset state.
• The SafetySignal is registering RES_HOT. Charge
is stopped and the LTC4110 enters the SMBus OFF
state.
• The AC power is no longer present (DCDIV < V
AC
or
DCIN < UVLO). Charge is stopped and the LTC4110
enters the reset state.
• ALARM_INHIBITED is set in the ChargerStatus() register.
Charge is stopped and the LTC4110 enters the SMBus
OFF state.
• CHARGE_INHIBIT is set in the BBuControl() register.
Charge is stopped. Clearing CHARGE_INHIBIT will en-
able the LTC4110 to resume charge. The t
TIMEOUT
timer
does not pause when CHARGE_INHIBIT is set.
• RESET_TO_ZERO is set in the BBuControl() register.
The LTC4110 enters the SMBus OFF state.
• Writing a zero value to the ChargeVoltage() or to the
ChargeCurrent() register. Charge is stopped and the
LTC4110 enters the SMBus OFF state.
• The CAL_START bit in the BBuControl() register is set.
Charge is stopped and the LTC4110 enters the calibra-
tion mode.
SMBus OFF STATE
This state is different from the reset state in that all charge
is disallowed regardless of the value of the thermistor. The
following conditions will affect the SMBus OFF state as
specifi ed below:
• The ChargeCurrent() AND ChargeVoltage() regis-
ters have both been written to non-zero values, the
battery thermistor is registering RES_COLD, RES_
IDEAL or RES_UR and CHARGE_INHIBT is clear. The
LTC4110 enters the SMBus preconditioning charge
state.