S-8204AAB-TCT1Y Datasheet, PDF (15/34 Pages) Seiko Instruments Inc – BATTERY PROTECTION IC

Rev.3.5_00
BATTERY PROTECTION IC FOR 3-SERIES OR 4-SERIES CELL PACK
S-8204A Series
4. Discharge overcurrent status
In the S-8204A Series, in batteries in the normal status, the discharging current increases more than a
certain value. As a result, if the status in which the VINI pin voltage increases to the level of V_DIOV1 or
more, the DOP pin gets the V_DD level. This is the discharge overcurrent status. At this time, the discharge
control FET is turned off and it stops discharging.
The S-8204A Series has three levels for discharge overcurrent detection (V_DIOV1, V_DIOV2, V_SHORT). In the
status of discharge overcurrent, the COP pin is set in high impedance. The VMP pin is pulled up to the
V_DD level by a resistor between VMP pin and VDD pin (R_VMD).
The S-8204A Series' operations against discharge overcurrent detection voltage 2 (V_DIOV2) and load short-
circuit detection voltage (V_SHORT) are as well in V_DIOV1.
The discharge overcurrent status is released if the following condition is satisfied.
(1) The VMP pin voltage gets V_DS − 1.2 V (typ.) or more.
5. Charge overcurrent status
In the S-8204A Series, in batteries in the normal status, the charge current increases more than a certain
value. As a result, if the status in which the VINI pin voltage decreases to the level of V_CIOV or less, the
COP pin is set in high impedance. This is the charge overcurrent status. At this time, the charge control
FET is turned off and it stops charging.
In this charge overcurrent status, the VMP pin is pulled up to the V_DD level by R_VMD. Also in the
overdischarge status, the function of charge overcurrent detection works.
The charge overcurrent status is released if the following condition is satisfied.
(1) The VMP pin voltage gets V_DS or less.
6. 0 V battery charge function
In the S-8204A Series, regarding how to charge a discharged battery (0 V battery), users are able to
select either function mentioned below.
(1) Allow to charge a 0 V battery (enable to charge a 0 V battery)
A 0 V battery is charged;
when the voltage of a charger is 0 V battery starting charger voltage (V_0CHA) or more.
(2) Inhibit charging a 0 V battery (unable to charge a 0 V battery)
A 0 V battery is not charged;
when the voltage of a charger is 0 V battery charge inhibition battery voltage (V_0INH) or less.
Caution When the VDD pin voltage is less than the minimum value of operation voltage between
VDD pin and VSS pin (V_DSOP), the operation of the S-8204A Series is not assured.
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