s-8241abtmc-gbtt2g Seiko Instruments Inc., s-8241abtmc-gbtt2g Datasheet - Page 20

• Manufacturer Part Number: s-8241abtmc-gbtt2g
• Description: Battery Protection Ic For 1-cell Pack
• Manufacturer: Seiko Instruments Inc.

20
BATTERY PROTECTION IC FOR 1-CELL PACK
S-8241 Series
4. Overdischarge Condition
5. Charger Detection
With power-down function
When the battery voltage drops below the overdischarge detection voltage (V
condition and it continues for the overdischarge detection delay time (t
control FET off and stops discharging. This condition is called overdischarge condition. After the discharging control
FET is turned off, the VM pin is pulled up by the R
difference between VM and VDD drops below 1.3 V (typ.) (the load short-circuiting detection voltage), current
consumption of the IC is reduced to the power-down current consumption (I
condition. The VM and VDD pins are shorted by the R
conditions.
The power-down condition is released when a charger is connected and the potential difference between VM and VDD
becomes 1.3 V (typ.) or higher (load short-circuiting detection voltage). At this time, the FET is still off. When the battery
voltage becomes the overdischarge detection voltage (V
normal condition from the overdischarge condition.
Without power-down function
When the battery voltage drops below the overdischarge detection voltage (V
condition and it continues for the overdischarge detection delay time (t
control FET off and stops discharging. When the discharging control FET is turned off, the VM pin is pulled up by the
R
V (typ.) (the load short-circuiting detection voltage), current consumption of the IC is reduced to the overdischarge
current consumption (I
R
When a charger is connected, the overdischarge condition is released in the same way as explained above in respect to
products having the power-down function. For products without the power-down function, in addition, even if the charger
is not connected, the S-8241 turns the discharging control FET on and changes to the normal condition from the
overdischarge condition provided that the load is disconnected and that the potential difference between VM and VSS
drops below the overcurrent 1 detection voltage (V
VM and VSS in the IC when the battery voltage reaches the overdischarge release voltage (V
If the VM pin voltage is lower than the charger detection voltage (V
connected to a charger, overdischarge hysteresis is released, and when the battery voltage becomes equal to or higher
than the overdischarge detection voltage (V
turned on). This action is called charger detection. (The charger detection reduces the time for charging in which
charging current flows through the internal parasitic diode in the discharging control FET) .
If the VM pin voltage is not lower than the charger detection voltage (V
connected to a charger, the overdischarge condition is released (the discharging control FET is turned on) as usual,
when the battery voltage reaches the overdischarge release voltage (V
*1. If the VM pin voltage is no less than the charger detection voltage (V
VMD
VMD
condition is connected to a charger, the overdischarge condition is released (the discharging control FET is turned
on) as usual, provided that the battery voltage reaches the overdischarge release voltage (V
resistor between VM and VDD in the IC. Meanwhile the potential difference between VM and VDD drops below 1.3
resistor in the IC under the overdischarge condition.
OPED
). This condition is called overdischarge condition. The VM and VDD pins are shorted by the
Seiko Instruments Inc.
DL
), the overdischarge condition is released (the discharging control FET is
VMD
IOV1
resistor between VM and VDD in the IC. Meanwhile the potential
), since the VM pin is pulled down by the R
VMD
DL
) or higher
resistor in the IC under the overdischarge and power-down
*1
CHA
, the S-8241 turns the FET on and changes to the
CHA
DU
DL
DL
) when a battery in overdischarge condition is
) or higher.
) or longer, the S-8241 turns the discharging
) or longer, the S-8241 turns the discharging
) when a battery in overdischarge condition is
CHA
PDN
), when the battery under overdischarge
). This condition is called power-down
DL
DL
) during discharging under normal
) during discharging under normal
DU
) or higher.
DU
VMS
) or higher.
resistor between
Rev.7.9
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