X3100 Xicor, X3100 Datasheet - Page 19

• 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
Figure 8. Over-Current Protection Mode—Event Diagram
Table 24. Over-Current Protection Mode—Event Diagram Description
Event
(1,2)
(2,3)
[0,1)
[1]
[2]
UVP/OCP
Event
VCS
Normal Operation Mode
V
The internal Over-current detection delay timer continues counting for T
P+
B+
OC
2
— Discharge FET is ON (OCP=Vss). Battery cells are permitted to discharge.
— VCS
— The device is in normal operation mode (i.e. not in a protection mode).
— Excessive current flows through the battery terminals P+, dropping the voltage. (See Figure 8.).
— The positive battery terminal voltage (P+) falls, and VCS
— The internal over-current detection delay timer begins counting down.
— The device is still in Normal Operation Mode
— The internal over-current detection delay timer times out, AND VCS
— The internal over-current sense circuitry switches the discharge FET OFF (UVP/OCP=Vcc).
— The device now begins a load monitor state by passing a small test current (I
— The device has now entered over-current protection mode.
— It is possible to change the status of UVPC and OVPC in the control register, although the status of pins
— The X3100/X3101 now continuously monitors the load resistance to detect whether or not an over-
0
OVP/LMON. This senses if an over-current condition (i.e. if the load resistance < 150k
across P+/P-.
UVP/OCP and OVP/LMON will not change until the device has returned from over-current protection
mode.
current condition is still present across the battery terminals P+/P-.
21
1
(VCS
T
OC
2
–VCS
2
1
) is less than the over-current threshold voltage (V
P+ = (RLOAD+RSENSE) x ILMON
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Over-Current Protection Mode
Event Description
21
exceeds V
3
Characteristics subject to change without notice.
T
OC
OCR
21
OC
is still above V
seconds.
OC
.
).
4
LMON
Normal Operation Mode
=7.5µA) out of pin
OC.
Ω
) still exists
Voc
V
V
V
SS
CC
SS
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