TS2208A/B
Li-Ion Battery Protector
Pin assignment
1. D
OUT
2. V
-
3. C
OUT
4. C
EXT
5. V
DD
6. V
SS
Ideal for One-Cell Rechargeable
Li-Ion Battery
General Description
The TS2208A/B series are over-charge/discharge protection ICs for rechargeable one-cell Lithium-ion batteries. They
bear an over-charge/over-discharge threshold for the battery cell voltage during charging/discharging process, and also
provide on-time protection when excess current or short circuit occurs.
The TS2208A/B series are essentially composed of a reference unit and three voltage detectors. During charging
process, when the cell voltage/V
DD
crosses the over-charge threshold voltage V
C1
, the over charge detector (COM1) will
switch the output pin (C
OUT
) to a low level within a delay time (t
C1
), and thus turning off the MOSFET connected to the
charging path. The C
OUT
pin may change to high level again when the V
DD
voltage falls below 鈥淰
C1
-V
HYS
鈥? or when V
DD
falls below V
C1
while the charger is disconnected from the battery pack.
During the discharging process, when the V
DD
voltage crosses the over-discharge threshold voltage (V
D1
), the
over-discharge detector (COM2) will switch D
OUT
to low level within a delay time (t
D1
), and thus turning off the MOSFET
connecting the discharging path. In the mean time, the TS2208A/B series will enter a low current standby mode. Once
into standby mode, it can only be released from standby after the battery pack is connected to a charger.
The conditions of excess current and short circuit protection are both determined according to the voltage at the V- pin.
As the voltage of V- pin reaches a greater value than V
OC
, which means an undesirable large current is flowing through
the path, D
OUT
will be switched to a low level and the path is cutoff after internally pre-set delay time (t
OC
) elapses. In the
case of short circuit, i.e. V- rises above V
SHORT
, the path will also be cutoff but with almost no delay time. Once the excess
current or short circuit fault is removed, the built-in resistor at the V- pin, typically 100kohm, will pull V- down to V
SS
and
bringing the IC back to normal operation.
Together with the application circuit, the TS2208A/B will function as a consummate protector for Li-ion battery packs
which leads to safety and long lifetime.
Features
Low current consumption
Supply current 3uA (typ) and standby current 0.1uA
High withstand voltage up to 22V (VDD ~ V-)
High accuracy voltage detection
Over charge detector
Over discharge detector
Over current and short circuit protection
Small package of SOT-26
Ordering Information
Part No.
TS2208ACX6
TS2208BCX6
Note: Marking BXX,
XX
is wafer and assembly lot code (A~Z and 1~9)
Threshold Voltage
4.33V ~ 4.37V
4.26V ~ 4.30V
Reel
Black
White
Pin Description
No.
1
2
3
4
Symbol
D
OUT
V
-
C
OUT
C
EXT
Description
Output of over discharge detection
Pin for charger negative input
Output of over charge detection
Pin for external capacitor Setting
COM1 delay time
Applications
Over-charge and over-discharge protection for Li-ion
cell pack
High precision protectors for cell-phones and other
gadget using on board Li-ion cell battery
5
6
V
DD
V
SS
Power supply
Ground
TS2208A/B series
1-6
2003/12 rev. B
1
2
3
4
5
6
