SI9730 Datasheet, PDF (9/14 Pages) Vishay Siliconix – Dual-Cell Lithium Ion Battery Control IC

Si9730
Vishay Siliconix
Additionally, the battery as a whole can be undervoltage (UV),
where V_BATTERY < V_UVL. Note that this final condition is not
necessarily (though normally) mutually exclusive with the
other cell conditions: if one cell were at 0V, the other cell could
be in NO, and the battery could still be in UV.
The charger can be either present (ON) or not present (OFF);
the “X” in the table means the condition is true regardless of the
state of the charger. The load current can be either 0, normal
(0 < I_LOAD < I_ILIMIT) or a short (I_ILIMIT< I_LOAD) where I_ILIMIT is
set by V_ILIMIT/R_SENSE; the “X” in the table refers to a load
current that can be either 0 or normal. Finally, the switch can
be either ON, OFF, or cycling at either 1/8 or 7/8 duty cycle,
where the duty cycle refers to the portion of the period when
the switch is on; the notation On−>On simply means that the
switch does not change state, it remains on; the notation −>Off
means that the switch turns off regardless of its previous state.
STATE TRANSITION TABLE
High-Cell Voltage Low-Cell Voltage
NO
NO
NO−>OC
NO
NO
NO−>OC
NO−>OC
NO
NO
NO−>OC
OC
NO
NO
OC
OC
OC
NO
NO
OC
NO
NO
OC
NO−>ODC
NO
NO
NO−>ODC
NO−>ODC
NO
NO
NO−>ODC
ODC
NO
NO
ODC
ODC
ODC
UV
NO−>ODC
OC
OC
NO−>OC
NO
NO
UV
ODC
ODC
NO
ODC
ODC
NO
NO
NO
OC
OC
Charger On/Off
Off>On
Off
Off
Off
Off
Off−>On
Off−>On
Off−>On
Off
Off
Off
Off
Off
Off
Off
Off−>On
Off−>On
Off−>On
Off−>On
Off
Off
V<0
On
X
X
X
X
X
Load Current
X
0
0
Normal
Normal
X
X
X
Normal−>Short
Normal−>Short
Normal−>Short
0
0
Normal
Normal
X
X
X
X
0
0
X
Center Tap−>Open
Center Tap−>Open
Center Tap−>Open
Center Tap−>Open
Center Tap−>Open
Center Tap−>Open
Switch State
On−>On
On−>Off
On−>Off
Cycles at very high duty cycle
Cycles at very high duty cycle
Off−>Off
Off−>Off
Off−>Off
On−>Off
On−>Off
On−>Off
On−>Off
On−>Off
On−>Off
On−>Off
Off−>Cycle at 7/8 duty cycle
Off−>Cycle at 7/8 duty cycle
Off−>Cycle at 7/8 duty cycle
Off−>Cycle at 1/8 duty cycle
Cycle−>Off
Off
Off
Cycle at 1/8 duty cycle
−.>Off
−.>Off
−.>Off
−.>Off
−.>Off
Document Number: 70658
S-40135—Rev. F, 16-Feb-04
www.vishay.com
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