Battery Protection IC for 2-Serial to 4-Serial-cell Pack (Secondary Protection) S-8224A/B Series

The S-8224A/B Series is used for secondary protection of lithium-ion rechargeable batteries, and incorporates high-accuracy voltage detection circuits and delay circuits.
Short-circuits between cells accommodate series connection of two cells to four cells.
The S-8224B Series limits its CO pin output voltage to 11.5 V max., so an FET with the gate withstand voltage of 12 V can be used.

Features

High-accuracy voltage detection circuit for each cell
Overcharge detection voltage n (n = 1 to 4)
3.600 V to 4.700 V (50 mV step)
  Accuracy ±20 mV (Ta = +25°C)
  Accuracy ±25 mV (Ta = −10°C to +60°C)
Overcharge hysteresis voltage n (n = 1 to 4)*1
0.0 mV to −550 mV (50 mV step)
−300 mV to −550 mV Accuracy ±20%
−100 mV to −250 mV Accuracy ±50 mV
−50 mV Accuracy ±25 mV
0.0 mV Accuracy −25 mV to +20 mV
Delay times for overcharge detection are generated only by an internal circuit (external capacitors are unnecessary)
Overcharge detection delay time is selectable: 1 s, 2 s, 4 s, 6 s, 8 s
Overcharge release delay time is selectable: 2 ms, 64 ms
Built-in timer reset delay circuit
Output control function via CTL pin
Output form is selectable (S-8224A Series)
CMOS output, Nch open-drain output
Output logic is selectable (S-8224A Series)
Active “H”, active “L”
CO pin output voltage is limited to 11.5 V max. (S-8224B Series)*2
High-withstand voltage
Absolute maximum rating 28 V
Wide operation voltage range
3.6 V to 28 V
Wide operation temperature range
Ta = −40°C to +85°C
Low current consumption
During operation (VCU − 1.0 V for each cell): 0.25 μA typ., 0.6 μA max. (Ta = +25°C)
During overdischarge (VCU × 0.5 V for each cell): 0.3 μA max. (Ta = +25°C)
Lead-free (Sn 100%), halogen-free

*1. Select the overcharge hysteresis voltage calculated as the following formula. (Overcharge detection voltage n) + (Overcharge hysteresis voltage n) ≥ 3.4 V
*2. Only output logic active “H” is available.

Applications

  • Lithium-ion rechargeable battery packs (for secondary protection)