2

FN6429.1

February 22, 2007

Typical Applications

Pin Description

VIN (Pin 1)

VIN is the input power source. Connect to a wall adapter.

GND (Pin 2)

GND is the connection to system ground.

STATUS (Pin 3)

STATUS is an open-drain output indicating charging and

inhibit states. The STATUS pin is pulled LOW when the

charger is charging a battery. It will be turned into high

impedance when the charge current drops to IMIN. This high

impedance state will be latched until a recharge cycle or a

new charge cycle starts. When the charger is disabled, the

STATUS pin outputs high impedance.

TIME (Pin 4)

The TIME pin determines the oscillation period by

connecting a timing capacitor between this pin and GND.

The oscillator also provides a time reference for the charger.

GND (Pin 5)

GND is the connection to system ground.

EN (Pin 6)

EN is the enable logic input. Connect the EN pin to HIGH to

disable the charger. Connect the EN pin to LOW or leave it

floating to enable the charger. There is an internal 400k

Ω

pull-down resistor at this pin.

V2P8 (Pin 7)

This is a 2.8V reference voltage output. This pin provides a

2.8V voltage source when the input voltage is above the

POR threshold and outputs 0V otherwise. The V2P8 pin can

be used as an indication for adapter presence.

IREF (Pin 8)

This is the charge current programming and monitoring pin.

Connect a resistor between this pin and GND to set the

charge current during the constant current phase, as given

by Equation 1:

VSEN (Pin 9)

VSEN is the remote voltage sense pin. Connect this pin as

close to the battery positive terminal as possible. If the

VSEN pin is left floating, its voltage drops to 0V and the

charger operates in trickle mode.

VBAT (Pin 10)

VBAT is the connection to the battery. Typically a 10µF

Tantalum capacitor is needed for stability when there is no

battery attached. When a battery is attached, only a 0.1µF

ceramic capacitor is required.

V2P8

EN

GND

VBAT

IREF

VIN

5V WALL

ADAPTER

PACK

TIME

1µF

1k

Ω

1µF

4.7µF

100k

Ω

15nF

VSEN

R

BATTERY

ISL9201IRZ

1

Ω

STATUS

I

REF

80

R

IREF

-----------------

=

(EQ. 1)

(A)

ISL9201