
Seiko Instruments Inc
The S-8261 series are lithium-ion / lithium polymer rechargeable battery protection ICs incorporating high accuracy voltage detection circuit and delay circuit. The S-8261 series are suitable for protection of single-cell lithium ion/lithium polymer battery packs from overcharge, overdischarge and overcurrent.
FEATUREs
(1) Internal high accuracy voltage detection circuit
• Overcharge detection voltage 3.9 V to 4.4 V (applicable in 5 mV step)
Accuracy: ±25 mV (+25 °C) and ±30 mV (−5 °C to +55 °C)
• Overcharge hysteresis voltage 0.0 V to 0.4 V*1 Accuracy: ±25 mV
The overcharge hysteresis voltage can be selected from the range 0.0 V to 0.4 V in 50 mV step.
• Overdischarge detection voltage 2.0 V to 3.0 V (applicable in 10 mV step) Accuracy: ±50 mV
• Overdischarge hysteresis voltage 0.0 V to 0.7 V*2 Accuracy: ±50 mV
The overdischarge hysteresis voltage can be selected from the range 0.0 V to 0.7 V in 100 mV step.
• Overcurrent 1 detection voltage 0.05 V to 0.3 V (applicable in 10 mV step) Accuracy: ±15 mV
• Overcurrent 2 detection voltage 0.5 V (fixed) Accuracy: ±100 mV
(2) High voltage device is used for charger connection pins
(VM and CO pins: absolute maximum rating = 28 V)
(3) Delay times (overcharge: tCU, overdischarge: tDL, overcurrent 1: tlOV1, overcurrent 2: tlOV2) are generated
by an internal circuit. No external capacitor is necessary. Accuracy: ±20%
(4) Three-step overcurrent detection circuit is included.
(overcurrent 1, overcurrent 2 and load short-circuiting)
(5) 0 V battery charge function “available” / “unavailable” are selectable.
(6) Charger detection function and abnormal charge current detection function
• The overdischarge hysteresis is released by detecting negative voltage at the VM pin (−0.7 V typ.).
(Charger detection function)
• When the output voltage of the DO pin is high and the voltage at the VM pin is equal to or lower than the charger detection voltage (−0.7 V typ.), the output voltage of the CO pin goes low. (Abnormal charge current detection function)
(7) Low current consumption
• Operation mode 3.5 µA typ., 7.0 µA max.
• Power-down mode 0.1 µA max.
(8) Wide operating temperature range −40 °C to +85 °C
(9) Small package SOT-23-6, 6-Pin SNB(B)
*1. Overcharge release voltage = Overcharge detection voltage − Overcharge hysteresis voltage
(where overcharge release voltage < 3.8 V is prohibited.)
*2. Overdischarge release voltage = Overdischarge detection voltage + Overdischarge hysteresis voltage
(where overdischarge release voltage > 3.4 V is prohibited.)
APPLICATIONs
• Lithium-ion rechargeable battery packs
• Lithium polymer rechargeable battery packs