SM6780AS

NIPPON PRECISION CIRCUITS—2

BLOCK DIAGRAM

PIN DESCRIPTION

Number

Name

Description

1

TIME

Charge time select 3-level input.

2

LEDN

Charge indicator LED driver output.

Open-drain output. LOW-level output in quick charge mode. 1Hz pulse output when abnormal battery voltage or

temperature is detected during quick charge mode. High impedance output in supplemental and trickle charge

modes.

3BATT

Battery voltage detector input.

Connect a high-impedance resistor voltage divider between the poles of the battery for voltage detection.

4

VSS

Ground

5

TEMP

Battery temperature thermistor sensor voltage input

6

VDD

Supply

7

INH

Charge inhibit input.

Charging is stopped when HIGH. Charging resumes with the same charge parameters in force prior to the stop

when INH goes LOW again.

8

CHGN

Charger control output.

Open-drain output. Battery charging current flows when CHGN is high impedance. Charge current stops when

LOW. High-impedance output in quick charge mode, and pulse output in supplemental and trickle charge

modes.

Reference

Regulators

TEMP

Maximum

Cell-voltage Check

Input Select

Temp Check

BATT

OSC

A/D

−∆V

Function

Block

∆V/∆t

Function

Block

Timer Mode

Selector

Timing Control

Logic

Charge Control

Logic

CHG Driver

LED Driver

CHGN

VSS

LEDN

INH

VDD

VDD

VDD

TIME

VDD

DC

Input

Current

Source

NTC

Battery

Pack