BQ2084-V133 Datasheet, PDF (27/64 Pages) Texas Instruments – SBS v1.1-COMPLIANT GAS GAUGE FOR USE WITH THE bq29312

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bq2084-V133
SLUS640A – JUNE 2005 – REVISED JUNE 2005
Figure 3. Shutdown Flow Chart in Normal Operation
SBS MAC command 0x05
received
No
SBS.Current( ) <= 0?
Yes
No
Pack voltage < Vpack
threshold ?
Yes
bq2084 Enters Shutdown
Figure 4. Shutdown Flow Chart in SBS MAC
Reset Conditions
On power up, the entire IC is reset and data is loaded from Data Flash to configure the SBS Data and the battery
management solution. On a partial reset (loss of VCC but RBI holds RAM valid), a limited number of locations
are taken. These actions are the following:
• The AFE registers are rewritten.
• PackStatus() EDV2 flag is cleared.
• BatteryStatus() DISCHARGING flag is cleared.
• The charger and alarm broadcast period is set to 10 seconds between broadcasts.
COMMUNICATION
The bq2084-V133 includes an SMBus communication port. The SMBus interface is a 2-wire bidirectional protocol
using the SMBC (clock) and SMBD (data) pins. The communication lines are isolated from V_CC and may be
pulled up higher than VCC. Also, the bq2084-V133 does not pull these lines low if V_CC to the part is zero. The
communication ports allow a host controller, an SMBus compatible device, or other processor to access the
memory registers of the bq2084-V133. In this way a system can efficiently monitor and manage the battery.
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