X3100 Xicor, X3100 Datasheet - Page 14

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

X3100/X3101 – Preliminary Information
Table 20. Over-charge Protection Mode—Event Diagram Description
REV 1.1.8 12/10/02
Event
[0,1)
(1,2)
(2,3)
[1]
[2]
[3]
The internal over-charge detection delay timer continues counting for T
While in over-charge protection mode:
— Discharge FET is ON (UVP/OCP=V
— Charge FET is ON (OVP/LMON=V
— All cell voltages (V
— The device is in normal operation mode (i.e. not in a protection mode).
— The voltage of one or more of the battery cells (V
— The internal over-charge detection delay timer begins counting down.
— The device is still in normal operation mode
— Therefore, the internal over-charge sense circuitry switches the charge FET OFF (OVP/LMON=Vcc).
— The device has now entered over-charge protection mode.
— The battery cells are permitted to discharge via the discharge FET, and diode D
— The X3100 or X3101 monitors the voltages V
— (It is possible to change the status of UVP/OCP or OVP/LMON using the control register)
— All cell voltages fall below V
— The X3100/X3101 automatically switches charge FET=ON (OVP/LMON=Vss)
— The status of the discharge FET remains unaffected.
— Charging of the battery cells can now resume.
below the “Return from over-charge threshold” (V
CELL
The internal over-charge detection delay timer times out
-V
CELL4
OVR
) are below the over-charge voltage threshold (V
—The device is now in normal operation mode.
SS
SS
www.xicor.com
), and hence battery cells are permitted to receive charge.
).
V
CELL
Event Description
CELL1
still exceeds V
AND
CELL
OVR
-V
CELL4
).
), exceeds V
to determine whether or not they have all fallen
OV.
OV
OV
Characteristics subject to change without notice.
.
seconds.
2
OV
across the charge FET
).
14 of 40