10

ICS1722

Table 3: Charge Rate List

Mode Selection: AUX0, AUX1 Pins

The AUX0 and AUX1 inputs must be programmed by the user to

inform the ICS1722 of the desired auxiliary mode. When left

unconnected (open) these tri-level pins will float to about 2.3V.

When a low level is required, the pin must be grounded.

When a high level is required, the pin must be tied to V

DD

. The

voltage ranges for low (L), open (Z) and high (H) are listed in

Table 6, DC Characteristics. To program the AUX0 and AUX1

inputs, refer to the Mode Select List in Table 4. See the section on

Auxiliary Modes of Operation for additional information.

Table 4: Mode Select List

SEL0

SEL1

Charge Rate

Topping Charge

pulse Rate

Maintenance Charge Pulse

Rate

Fast Charge Timer

Duration (after reset)

L

L

4C (15 min)

one every 40 sec

one every 160 sec

21 min

L

H

2C (30 min)

one every 20 sec

one every 80 sec

39 min

L

Z

1.3C (45 min)

one every 13 sec

one every 53 sec

57 min

H

L

1C (60 min)

one every 10 sec

one every 40 sec

75 min

H

Z

C/1.5 (90 min)

one every 7 sec

one every 27 sec

110 min

H

H

C/2 (120 min)

one every 5 sec

one every 20 sec

144 min

Z

L

C/2.5 (150 min)

one every 4 sec

one every 16 sec

212 min

Z

Z

C/3 (180 min)

one every 3 sec

one every 13 sec

244 min

Z

H

C/4 (240 min)

one every 2 sec

one every 10 sec

275 min

See the section on Controller Operation for additional information on the topping charge and maintenance charge. See the section on Charge Termination

Methods for additional information on the charge timer.

AUX0

AUX1

Mode Selected

Mode Operation

L

L

Charging System Test

Charging system test for embedded applications

L

H

Direct Maintenance

Indefinite C/40 maintenance charge

Z

Z

Fast Charge

Default

Z

L

Discharge-Only

Battery discharge to 1V/cell

H

L

Discharge-to-Charge

Battery discharge to 1V/cell followed by the selected charge mode

H

Z

Condition

Timed C/10 topping charge followed by a C/40 maintenance charge

H

H

Ten Hour Timer

Limits total charge including the maintenance charge to 10 hours