s-8211caj-m5t1g Seiko Instruments Inc., s-8211caj-m5t1g Datasheet - Page 19

• Manufacturer Part Number: s-8211caj-m5t1g
• Description: Battery Protection Ic For 1-cell Pack
• Manufacturer: Seiko Instruments Inc.

Rev.5.0
Operation
Remark Refer to the “Battery Protection IC Connection Example”.
1. Normal Status
2. Overcharge Status
This IC monitors the voltage of the battery connected between the VDD pin and VSS pin and the voltage difference
between the VM pin and VSS pin to control charging and discharging. When the battery voltage is in the range from
overdischarge detection voltage (V
from the charge overcurrent detection voltage (V
both the charging and discharging control FETs on. This condition is called the normal status, and in this condition
charging and discharging can be carried out freely.
The resistance (R
are not connected in the normal status.
Caution When the battery is connected for the first time, discharging may not be enabled. In this case, short
When the battery voltage becomes higher than overcharge detection voltage (V
status and detection continues for the overcharge detection delay time (t
charging control FET off to stop charging. This condition is called the overcharge status.
The resistance (R
are not connected in the overcharge status.
The overcharge status is released in the following two cases ( (1) and (2) ).
(1) In the case that the VM pin voltage is higher than or equal to the charge overcurrent detection voltage (V
(2) In the case that the VM pin voltage is higher than or equal to the discharge overcurrent detection voltage (V
Caution 1. If the battery is charged to a voltage higher than overcharge detection voltage (V
The discharge is started by connecting a load after the overcharge detection, the VM pin voltage rises more than
the voltage at VSS pin due to the V
the parasitic diode in the charging control FET. If this VM pin voltage is higher than or equal to the discharge
overcurrent detection voltage (V
lower than or equal to the overcharge detection voltage (V
For the actual application boards, changing the battery voltage and the charger voltage simultaneously enables to
measure the overcharge release voltage (V
equivalent voltage level to the battery voltage. The charger keeps VM pin voltage higher than or equal to the
charge overcurrent detection voltage (V
voltage (V
overcharge release voltage (V
_00
and is lower than the discharge overcurrent detection voltage (V
status when the battery voltage falls below the overcharge release voltage (V
S-8211C Series releases the overcharge status when the battery voltage falls below the overcharge detection
voltage (V
the VM pin and VSS pin or connect the charger to restore the normal status.
2. When a charger is connected after overcharge detection, the overcharge status is not released
battery voltage does not fall below overcharge detection voltage (V
connected, discharge overcurrent detection and load short-circuiting detection do not function
until the battery voltage falls below overcharge detection voltage (V
has an internal impedance of tens of mΩ, the battery voltage drops immediately after a heavy
load that causes overcurrent is connected, and discharge overcurrent detection and load short-
circuiting detection function.
even if the battery voltage is below overcharge release voltage (V
released when the VM pin voltage goes over the charge overcurrent detection voltage (V
removing the charger.
DIOV
CU
).
). S-8211C Series releases the overcharge status when the battery voltage falls below the
VMD
VMD
) between the VM pin and VDD pin, and the resistance (R
) between the VM pin and VDD pin, and the resistance (R
CL
).
DL
DIOV
) to overcharge detection voltage (V
), S-8211C Series releases the overcharge status when the battery voltage is
f
voltage of the parasitic diode, because the discharge current flows through
Seiko Instruments Inc.
CIOV
) and lower than or equal to the discharge overcurrent detection
CIOV
CL
BATTERY PROTECTION IC FOR 1-CELL PACK
).
) to discharge overcurrent detection voltage (V
In this case, the charger is always necessary to have the
CU
).
DIOV
CU
CU
), S-8211C Series releases the overcharge
) or longer, the S-8211C Series turns the
), and the VM pin voltage is in the range
VMS
VMS
CL
) between the VM pin and VSS pin
) between the VM pin and VSS pin
CU
).
) during charging in the normal
CL
CU
CU
). The overcharge status is
) even when a heavy load is
). Since an actual battery
S-8211C Series
DIOV
), the IC turns
CU
) and the
CIOV
CIOV
DIOV
) by
19
),
),