S-8250AAB-I6T1U Datasheet, PDF (14/36 Pages) Seiko Instruments Inc – BATTERY PROTECTION IC

BATTERY PROTECTION IC WITH DISCHARGE CONTROL FUNCTION FOR 1-CELL PACK
S-8250A Series
Rev.1.3_02
 Operation
Remark Refer to " Battery Protection IC Connection Example".
1. Normal status
The S-8250A Series monitors the voltage of the battery connected between the VDD pin and VSS pin, the voltage
between the VM pin and VSS pin and the voltage between the CTL pin and VSS pin to control charging and
discharging.
1. 1 CTL pin control logic active "H"
When the battery voltage is in the range from the overdischarge detection voltage (V_DL) to the overcharge
detection voltage (V_CU), and the VM pin voltage is in the range from the charge overcurrent detection voltage
(V_CIOV) to the discharge overcurrent detection voltage (V_DIOV), the S-8250A Series turns both the charge and
discharge control FETs on if the CTL pin voltage is equal to or lower than the CTL pin voltage "L" (V_CTLL). This
condition is called the normal status, and in this condition charging and discharging can be carried out freely.
The resistance between the VM pin and VDD pin (R_VMD) and the resistance between the VM pin and VSS pin
(R_VMS) are not connected in the normal status.
1. 2 CTL pin control logic active "L"
When the battery voltage is in the range from the overdischarge detection voltage (V_DL) to the overcharge
detection voltage (V_CU), and the VM pin voltage is in the range from the charge overcurrent detection voltage
(V_CIOV) to the discharge overcurrent detection voltage (V_DIOV), the S-8250A Series turns both the charge and
discharge control FETs on if the CTL pin voltage is equal to or higher than the CTL pin voltage "H" (V_CTLH). This
condition is called the normal status, and in this condition charging and discharging can be carried out freely.
The resistance between the VM pin and VDD pin (R_VMD) and the resistance between the VM pin and VSS pin
(R_VMS) are not connected in the normal status.
Caution When the battery is connected for the first time, the S-8250A Series may not be in the normal status.
In this case, short the VM pin and VSS pin, or set the VM pin voltage at the level of V_CIOV or more
and at the level of V_DIOV or less by connecting the charger. The S-8250A Series then becomes the
normal status.
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