ltc1760 Linear Technology Corporation, ltc1760 Datasheet - Page 21

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

OPERATIO
TERMINATE_CHARGE_RESERVED Bit
The read only TERMINATE_CHARGE_RESERVED bit is
used by the LTC1760 to determine if charging may con-
tinue.
Allowed values are:
OVER_TEMP_ALARM Bit
The read only OVER_TEMP_ALARM is used by the LTC1760
to determine if charging may continue.
Allowed values are:
TERMINATE_DISCHARGE_ALARM Bit
The read only TERMINATE_DISCHARGE_ALARM bit is
used by the LTC1760 to determine if discharge from the
battery is still allowed. This is used for power path man-
agement and battery calibration.
Allowed values are:
FULLY_DISCHARGED Bit
The read only FULLY_DISCHARGED bit is used by the
LTC1760 to determine if discharge from the battery is still
allowed. This is used for power path management and
battery calibration.
Allowed values are:
'b1: The LTC1760 will not charge this battery.
'b0: The LTC1760 may charge this battery if other
conditions permit charging.
'b1: The LTC1760 will not charge this battery.
'b0: The LTC1760 may charge this battery if other
conditions permit charging.
'b1: The LTC1760 will terminate calibration and should
try to not use this battery in the power path. When all
other power paths fail the LTC1760 will ignore this
alarm and still try to supply system power from this
source.
'b0: The LTC1760 may continue discharging this
battery.
'b1: The LTC1760 will terminate calibration and should
try to not use this battery in the power path. When all
other power paths fail the LTC1760 will ignore this
alarm and still try to supply system power from this
source.
U
2.3.11 AlertResponse ()
Description:
The SMBus Host uses the Alert Response Address (ARA)
to quickly identify the generator of an SMBALERT# event.
Purpose:
The LTC1760 will respond to an ARA if the SMBALERT
signal is actively pulling down the SMBALERT# bus. The
LTC1760 will follow the prioritization reporting as defined
in the “System Management Bus Specification”.
SMBus Protocol: A 7-bit Addressable Device Responds to
an ARA.
Output:
The device address will be sent to the SMBus Host. The
LTC1760 device address is 0x14 (or 0x0a if just looking at
the 7 bit address field).
The following events will cause the LTC1760 to pull-down
the SMBALERT# bus through the SMBALERT pin:
Refer to "Section 2.2" for bit mapping.
2.4 SMBus Dual Port Operation
The SMBus Interface includes the LTC1760’s SMBus
controller, as well as circuitry to arbitrate and connect the
battery and SMBus Host interfaces. The SMBus controller
generates and interprets all LTC1760 SMBus functions.
The dual port operation allows the SMBus Host to be
connected to the SMBus of either battery by setting the
SMB_BAT[4:1] nibble. Arbitration is handled by stretch-
ing an SMBus start sequence when a bus collision might
occur. Whenever configurations are switched, the LTC1760
will generate a harmless SMBus reset on SMB1 and SMB2
as required. The four possible configurations are illus-
trated in Figure 1. Sample SMBus communications are
shown in Figures 2 and 3.
'b0: The LTC1760 may continue discharging this
battery.
• Change of AC_PRESENT in the
• Change of BATTERY_PRESENT in the
• Internal power on reset condition.
BatterySystemStateCont() function.
BatterySystemState() function.
LTC1760
21
1760f