CMOS IC Application Note

S-8209A Series Usage Guidelines

Seiko Instruments Inc.

11

1. 4. 2 Low ratio of bypass current to charge current

When the ratio of bypass current to charge current is low, repeating cell-balance cycle enables to adjust

cell-balance.

Charger: a constant current charger (0.1 C = 290 mA)

S-8209AAA charge cell-balance, 0.1 C constant current charger

4.2

4.1

4.0

3.9

3.8

0

120

180

240

300

360

420

480

Charger connection

Time [min.]

BAT3

BAT2

BAT1

60

Figure 5

Test conditions

Test circuit: Figure 1

Battery: 3-series cell lithium ion rechargeable battery, Nominal capacitance: 2.9 Ah, Size: 18650

Ω (1 W) → bypass current = 4.1 V / 51 Ω = 80 mA