ltc1760 Linear Technology Corporation, ltc1760 Datasheet - Page 25

• Manufacturer Part Number: ltc1760
• Description: Dual Smart Battery System Manager
• Manufacturer: Linear Technology Corporation

OPERATIO
6. An SMBus Host write asserts the LTC1760
BatterySystemStateCont(CHARGING_INHIBIT) high.
7. Hardware controlled charging inhibit is asserted (MODE
low with V
8. The thermistor of the battery being charged indicates
COLD-RANGE and the battery has been charged for longer
than t
9. The thermistor of the battery being charged indicates
UNDER-RANGE and the battery has been charged for
longer than t
10. The thermistor of the battery being charged indicates
HOT-RANGE.
11. Any SMBus communication line is grounded for
longer than t
12. BatterySystemStateCont(POWER_NOT_GOOD) is
high.
13. The emergency off feature has been asserted using the
DCDIV input pin.
3.3 Wake-Up Charging Current and Voltage Limits
The wake-up charging current is fixed at I
values of I
mode described in “Section 10”.
The wake-up charging voltage is not limited by the V
function.
3.4 Controlled Charging Initiation
All of the following conditions must be met in order to
allow controlled charging of a given battery. One or both
batteries may be control charged at a time.
1. The battery thermistor must be COLD-RANGE, IDEAL-
RANGE, or UNDER-RANGE.
2. AC must be present.
3. BatterySystemStateCont(CHARGING_INHIBIT) must be
de-asserted (or low).
4. Hardware controlled charging inhibit must be
de-asserted (MODE not low with V
TIMEOUT
DDS
LIMIT
TIMEOUT
QUERY.
.
high).
. Wake-up charging uses the low current
U
.
DDS
high).
WAKE-UP
for all
LIMIT
5. The battery responds to an LTC1760 master read of
Alarm() with all charge alarms deasserted.
6. The battery responds to an LTC1760 master read of
ChargingVoltage() with a non zero voltage request value.
7. The battery responds to an LTC1760 master read of
Voltage().
8. The battery responds to an LTC1760 master read of
ChargingCurrent() with a non zero current request value.
9. The battery responds to an LTC1760 master read of
Current().
The following charging related functions are polled each
t
ChargingCurrent(), and Current().
3.5 Controlled Charging Termination
The LTC1760 will terminate controlled charging when any
of the following conditions are met:
1. Battery removal, or thermistor indicating OVER-RANGE.
2. AC removal.
3. The SMBus Host issues a calibration request by setting
BatterySystemStateCont(CALIBRATE) high.
4. An LTC1760 master read of ChargingCurrent() return-
ing a zero current request.
5. An LTC1760 master read of ChargingVoltage() return-
ing a zero voltage request.
6. Any of the following AlarmWarning() bits asserted high:
Note that the LTC1760 ignores all writes from the battery.
Each battery’s charge alarm is cached inside the LTC1760.
This bit will be set when any of the upper four bits of the
battery’s AlarmWarning() response are set.
QUERY
OVER_CHARGED_ALARM
TERMINATE_CHARGE_ALARM
TERMINATE_CHARGE_RESERVED
OVER_TEMP_ALARM
: Alarm(), ChargingVoltage(), Voltage(),
LTC1760
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