Datasheet

BATTERY PROTECTION IC FOR SINGLE-CELL PACK
Rev.4.1_00
S-8261 Series
Seiko Instruments Inc.
23
8. DP Pin
The DP pin is a test pin for delay time measurement and it should be open in the actual application. If a capacitor
whose capacitance is larger than 1000 pF or a resistor whose resistance is less than 1 MΩ is connected to this pin,
error may occur in the delay times or in the detection voltages.
9. 0 V Battery Charging Function “Available”
This function is used to recharge the connected battery whose voltage is 0 V due to the self-discharge. When the 0 V
battery charge starting charger voltage (V
0CHA
) or higher is applied between EB+ pin and EB− pin by connecting a
charger, the charging control FET gate is fixed to VDD pin voltage. When the voltage between the gate and source of
the charging control FET becomes equal to or higher than the turn-on voltage due to the charger voltage, the charging
control FET is turned on to start charging. At this time, the discharging control FET is off and the charging current
flows through the internal parasitic diode in the discharging control FET. When the battery voltage becomes equal to
or higher than the overdischarge detection voltage (V
DL
) and the overdischarge hysteresis voltage (V
HD
), the S-8261
Series enters the normal condition.
Caution Some battery providers do not recommend charging for completely self-discharged battery. Please
ask battery providers before determine whether to enable or inhibit the 0 V battery charging
function.
Remark The 0 V battery charge function has higher priority than the abnormal charge current detection function.
Consequently, a product with the 0 V battery charging function is enabled charges a battery forcibly and
abnormal charge current cannot be detected when the battery voltage is low.
10. 0 V Battery Charging Function “Unavailable”
This function inhibits the recharging when a battery that is short-circuited (0 V battery) internally is connected. When
the battery voltage is the 0 V battery charge inhibition battery voltage (V
0INH
) or lower, the charging control FET gate is
fixed to EB− pin voltage to inhibit charging. When the battery voltage is the 0 V battery charge inhibition battery
voltage (V
0INH
) or higher, charging can be performed.
Caution Some battery providers do not recommend charging for completely self-discharged battery. Please
ask battery providers before determining the 0 V battery charging function.