LTC4110
23
4110fb
REGISTER RESET STATE
The SHDN pin will reset all logic registers when taken high,
but only if DCIN is present as determined by DCDIV > V
AC
+ V
ACH
and DCIN above UVLO. Micropower shutdown
state will not be entered, but the LTC4110 will be idle and
not able to enter charge or calibration modes. If SHDN is
switched low then normal operation will resume.
While in register reset state, charge and calibration modes
are inhibited, and all registers including the backup fault bit
register are set to their default states and the internal timer
is reset. The status pin ACPb is active, but GPIO1, GPIO2
and GPIO3 are reset to their default states. The SMBus is
enabled, however, it is not able to communicate with the
LTC4110. The DCIN to DCOUT PowerPath controller is
functional and the V
DD
and V
REF
pin voltages remain.
MICROPOWER SHUTDOWN STATE
If the SHDN pin remains high when DCIN is removed as
detected by the undervoltage lockout UVLO (see V
UVD
),
micropower shutdown is entered, battery backup mode is
inhibited and all registers are reset. During this condition,
the level of the SHDN pin is ignored and has no effect.
OPERATION
#
Logic Event (T = True, F = False) [Notes]
Notes and/or Actions (T = True, F = False)
1
RES_OR = F & DCDIV pin = T & SHDN pin = F & CAL_FLT = F &
CAL_START = T
CAL_COMPLETE = F
(Calibration started while in Reset {Idle or Cold Power-Up})
2
RES_OR = F & DCDIV pin = T & SHDN pin = F & CAL_FLT = F &
CAL_START = T
I
CHG
or IPPC = Off & All Timers = Reset & CAL_COMPLETE = F
(Calibration was initiated while in any mode other than Reset.)
3
[Calibration Automatically Started]
I
CAL
= ON & CAL_ON = T
4
V
BAT
< V
CAL
[Battery has reached Discharge]
I
CAL
= Off & CAL_ON = F & CAL_COMPLETE = T
(Normal Calibration Cycle)
5
V
BAT
< V
CAL
[Battery is Discharged]
CAL_COMPLETE = T
(Battery is already discharged. Cancel Calibration.)
6
AlarmWarning() command is sent by Smart Battery over SMBus
with any of the following bits set to True:
OVER_TEMP_ALARM or Reserved ALARM or
TERMINATED_DISCHARGE_ALARM]
I
CAL
= Off & CAL_ON = F & ALARM_INHIBITED = T
(ALARM_INHIBITED bit is found in ChargeStatus())
7
CAL_RESET = T
I
CAL
= Off & CAL_ON = F & CAL_COMPLETE = F & CAL_FLT = F
8
Or
Or
Or
RES_HOT = T & RES_UR = F [See ChargeStatus()]
RES_OR = T [Bat Removed, See ChargeStatus()]
V
OVP
= T [Output Over-Voltage condition sensed)]
I
BDT
= T [Output Back Drive Current condition sensed)]
I
CAL
= Off & CAL_ON = F & CAL_FLT = T
9
Or
Or
Or
DCDIV pin = F
SHDN pin = T
V
UVD
= T
POR_RESET = T [See ChargeMode()]
I
CAL
= Off & CAL_ON = F & ALARM_INHIBITED = F &
CHARGE_INHIBITED = F
Figure 7. Calibration State Diagram
4110 F07
1
3
2
6, 9
8
(CALIBRATION FAULT)
7
CALIBRATION
RUNNING
ANY
STATE
RESUME
STATE
CALIBRATION
START
YES
NO
5 (BATTERY IS DEAD)
4
(CALIBRATION
COMPLETED)
RESET
CALIBRATION
MODE?
