2

ICS1722

Pin Configuration

Pin Definitions

ICS1722

CHG

DCHG

PFN

CMN

MMN

SEL1

AUX0

AUX1

OPREF

VIN

VDD

SEL0

VSS

RC

MRN

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

unused

16-Pin DIP or SOIC

Pin Number

Pin Name

Type

Definition

1

CHG

OUT

Active high TTL compatible signal used to turn on an external current source to provide current to charge

the battery.

2

DCHG

OUT

Active high TTL compatible signal available to turn on a discharge circuit.

3

PFN

OUT

Polling detect indicator. An active low turns on an external indicator to show the controller is polling for

the presence of the battery.

4

MMN

OUT

Maintenance mode indicator. An active low turns on an external indicator showing the battery is either in

the topping charge, maintenance charge or auxiliary condition mode. The indicator flashes during the

auxiliary discharge mode.

5

CMN

OUT

Charge mode indicator. An active low turns on an external indicator to show the controller is either in a

soft start charge or fast charge.

6

SEL0

IN

Tri-level input used with the SEL1 pin to program the device for the desired charge rate.

7

VSS

Ground.

8

SEL1

IN

Tri-level input used with the SEL0 pin to program the device for the desired charge rate.

9

MRN

IN

Master reset signal. A logic low pulse greater than 700 ms initiates a device reset.

10

RC

IN

An external resistor and capacitor sets the frequency of the internal clock.

11

AUX0

IN

Tri-level input used with the AUX1 pin to program the device for an auxiliary operating mode.

12

AUX1

IN

Tri-level input used with the AUX0 pin to program the device for an auxiliary operating mode.

13

OPREF

IN

Open circuit (no battery) voltage reference. An external resistor divider on this pin sets the open circuit

voltage reference used to detect the presence of a battery.

14

VIN

IN

Battery voltage normalized to one cell with an external resistor divider.

15

unused

Ground.

16

VDD

Device supply =+5.0 VDC

Note:

Pins 9 and 13 have an internal pull-up.

Pins 6,8,11,12 float to 2.3V when unconnected.