LTC4110EUHF LINER [Linear Technology], LTC4110EUHF Datasheet - Page 21

• Manufacturer Part Number: LTC4110EUHF
• Description: Battery Backup System Manager
• Manufacturer: LINER [Linear Technology]

OPERATION
Note: For all charge states, V
be set to indicate calibration in progress. Soft-start ramps
the discharge current at a rate set by the capacitor on the
I
how far the battery cell voltage will be discharged during
calibration can be programmed with the V
default = 2.75V/cell, lead acid default = 1.93V/cell, Smart
NiMH/NiCd default = 0.95V/cell). When the limit is reached
calibration is terminated, the CAL_COMPLETE bit in the
BBuStatus() register is set, the CAL_ON bit in the BBuS-
tatus() register will be cleared and the charge mode is
TH
#
1
2
3
4
5
6
7
8
9
pin (typically 10ms with 0.1μF capacitor). A limit to
Logic Event (T = True, F = False) [Notes]
Or
Or
Or
Or
Or
Or
Or
Or
Or
Or
RES_OR = F & DCDIV pin = T & SHDN pin = F & CHARGE_INHIBITED = F &
CHG_FLT = F
V
ChargingVoltage() & ChargingCurrent() ≠ 0 sent
ChargingVoltage() or ChargingCurrent() = 0 sent
RESET_TO_ZERO = T [See ChargeMode()]
CHARGE_INHIBIT = T [See ChargeMode()]
DCDIV pin = F
RES_OR = T [Bat Removed, See ChargeStatus()]
SHDN pin = T
V
POR_RESET = T [See ChargeMode()]
RES_HOT = T & RES_UR = F [See ChargeStatus()]
RES_HOT = F [See ChargeStatus()]
V
V
AlarmWarning() command is sent by Smart Battery over SMBus with any of
the following bits set to True:
OVER_CHARGED_ALARM
TERMINATE_CHARGE_ALARM
Reserved ALARM
OVER_TEMPERATURE_ALARM
AR
UVD
BOV
BOV
= T [AutoRestart]
= T
= F
= T
CHARGE
STATE
7
5
ANY
CHG
is always active
Figure 5. SLA Charge State Diagram (Does Not Include Calibration)
(OVERTEMPERATURE)
(BATTERY OVP)
STOPPED
STOP
PWM
CAL
pin (Li-Ion
RESUME
CHARGE
STATE
8
6
automatically entered to begin recharging the battery. If
the GPIO3 is confi gured as a calibration complete status
output (CAL_COMPLETEb), it will be forced low until reset
by the CAL_RESET write bit. Calibration is inhibited during
backup or shutdown modes. Calibration is also inhibited
when a thermistor is sensed absent.
During calibration, user-programmable supply back-drive
protections are provided. These protections prevent a
reversal of current into the main supply and/or possibly
raising the supply voltage to unsafe levels should the
CHARGE
RESET
1
Notes and/or Actions (T = True, F = False)
I
ALARM_INHIBITED = F
I
I
ALARM_INHIBITED = F
I
I
PWM stopped. Timers remain running.
PWM restarted.
I
(ALARM_INHIBITED bit is found in ChargeStatus())
CHG
CHG
CHG
CHG
CHG
CHG
= On & CHG = T
= Off & CHG = F
= Off & CHG = F & CHARGE_INHIBITED = F &
= Off & CHG_FLT = T
= On & CHG_FLT = F
= Off & CHG = F & ALARM_INHIBITED = T
4
3
2
CHARGE
STATE
STOP
ANY
9
LTC4110
4110 F05
21
4110fa