APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

TIMER

APM8601

Document number: DS35138 Rev. 1 - 2

2 of 14

www.diodes.com

December 2010

© Diodes Incorporated

Pin Descriptions

Name

Pin #

Description

BAT

1, 7

Connection to the

Battery

The battery is charged via this pin and the BAT voltage is constantly monitored.

Connect a bypass capacitor between BAT and GND (2.2µF).

SETI

2

Charge Current

programming

The maximum charge current is programmed using a resistor from SETI to GND.

This also determines the prequal current charging level and top-off threshold.

THM

3

Thermistor Input

To monitor the battery temperature, connect a 10k

Ω NTC thermistor. Place this

thermistor as close as possible to the battery. Connect THM to GND if

temperature measurement is not required.

GND

4

Ground

Ground connection.

CT

5

Charge Timing

Connecting a capacitor from CT to GND will set the time-outs for prequal, top-off

and fast-charge. Connecting CT direct to GND disables these timers.

USEL

6

USB Charge

Select

Logic input to program the charge current in USB charging mode.

EN

8

Enable

(active-low)

The charger is enabled when this input is low. To start the charger connect

EN

to GND. Drive this input high to disable the charger.

USB

9

USB Input

USB supply input. Connect a bypass capacitor (1µF) from USB to GND.

POK

10

Power OK

(active-low)

When a valid input source is connected, this open-drain output is pulled low.

CHG

11

Charge Status

(active-low)

Open-drain output that indicates the charging status. It is active only in the fast-

charge state and goes high-impedance when the charger is either disabled or in

prequal or top-off mode.

DC

12, 13

DC Input

DC supply input. The recommended input voltage is between 4.32V and 7V. This

input is capable of withstanding up to 28V. Connect both DC pins together on the

PCB. It is recommended to connect a bypass capacitor (1µF) from DC to GND.

FLT

14

Fault Flag

(active-low)

If the prequal or fast-charge timers expire and the charging threshold voltage is

EP

Exposed Pad

For optimal thermal performance connect to copper on PCB (electrically this can

be GND).