X3100 Xicor, X3100 Datasheet - Page 13

• Manufacturer Part Number: X3100
• Description: 3 or 4 Cell Li-Ion Battery Protection and Monitor IC
• Manufacturer: Xicor

X3100/X3101 – Preliminary Information
REV 1.1.8 12/10/02
over-charge and over-discharge protection circuitry is on
for approximately 2ms in each 125ms period. Over-
current monitoring is continuous. In monitor mode (see
page 20) over-charge and over-discharge monitoring is
also continuous.
Over-charge Protection
The X3100 and X3101 monitor the voltage on each
battery cell (V
time exceeding T
switched OFF (OVP/LMON=V
entered Over-charge protection mode (Figure 5). The
status of the discharge FET (via pin UVP) will remain
unaffected.
While in over-charge protection mode, it is possible to
change the state of the OVPC bit in the control register
such
Although the OVPC bit in the control register can be
changed, the change will not be seen at pin OVP until
the X3100 or X3101 returns from over-charge
protection mode.
The over-charge detection delay T
capacitor (C
Figure 5. Over-charge Protection Mode—Event Diagram
OVP/LMON
that
Event
V
CELL
OV
OVP/LMON=Vss
CELL
) connected between pin OVT and GND.
0
OV
). If for any cell, V
Normal Operation Mode
, then the Charge FET will be
CC
). The device has now
(Charge
OV
, is varied using a
CELL
1
T
> V
OV
FET=ON).
OV
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for a
2
A typical delay time is shown in Table 10. The delay T
that results from a particular capacitance C
approximated by the following linear equation:
Table 19. Typical over-charge detection time
The device further continues to monitor the battery cell
voltages, and is released from over-charge protection
mode when V
or X3101 is released from over-charge protection
mode, the charge FET is automatically switched ON
(OVP/LMON=V
charge protection mode, the status of the discharge
FET (pin UVP/OCP) remains unaffected.
The value of V
shown in Table 4 by setting bits VOV1, VOV0. These bits
are set by using the WCFIG instruction to write to the
configuration register.
Over-charge
Symbol
Protection
Mode
T
OV
CELL
SS
T
OV
OV
). When the device returns from over-
< V
Characteristics subject to change without notice.
(s) ≈ 10 x C
can be selected from the values
0.1µF
3
C
OVR
OV
, for all cells. When the X3100
Normal Operation Mode
OV
(µF).
1.0s (Typ)
Delay
OV
V
V
OV
OVR
V
, can be
V
CC
SS
13 of 40
OV