SM6781BV

NIPPON PRECISION CIRCUITS—8

BATT Input

The voltage applied to the BATT input, used for battery voltage detection, is a voltage potential, derived by a

voltage divider resistor network (100k

Ω or higher recommended) or other means, that represents the voltage of

a single battery cell during charging. If a single cell only is under charge, a current limiting resistor (100k

Ω or

higher is recommended) should be connected between the battery and BATT input.

Operating Mode vs. BATT Input Voltage

Charging Operating Status

Figure 5. BATT connection example (multiple)

BATT pin

N

Rb

Ra

N:Number of cells

Current

Source

Rb

Ra

= N

− 1

Figure 6. BATT connection example (single)

BATT pin

100k

Ω

Current

Source

NG

NG

Battery

check

Valid

Valid

Quick

charge

−∆V

detect

Battery voltage

[V]

2.0

1.0

0.6

0

− 1.5

− 0.5

Valid

Standby

mode

Charging status

Conditions

CHGN output

LEDN output

Internal timer

INH

Battery

check OK

Quick charge

LOW

Yes

High impedance

LOW (ON)

Count

Quick charge hold

LOW

No

LOW

1Hz (pulsing)

Hold

Quick charge inhibit

HIGH

–

LOW

1Hz (pulsing)

Hold

Quick charge finish

LOW

Yes

LOW

High impedance (OFF)

Reset

Standby

–

–

High impedance

High impedance (OFF)

Reset