ICS1702 Galaxy Power, Inc., ICS1702 Datasheet - Page 10

• Manufacturer Part Number: ICS1702
• Description: 20 Pin Quicksaver Full-featured Charge Controller For Ni-cd & Ni-mh Batteries.
• Manufacturer: Galaxy Power, Inc.

ICS1702
Direct Maintenance Mode
The ICS1702 can enter directly into the C/40 maintenance mode
for cells that require a maintenance charge only. The direct
maintenance mode is activated by setting the AUX0 pin low (L)
and the AUX1 pin high (H), and resetting the device. The SEL0
and SEL1 pins must be set based on the charging current and the
battery capacity. The formula
gives the charge rate. Use Table 4 to find the correct SEL0 and
SEL1 settings. The maintenance charge is applied until the battery
is removed, upon which the ICS1702 will enter the polling detect
mode. The ICS1702 will enter the direct maintenance mode upon
initial power-up or after a master reset. The MMN indicator will be
active during this mode.
Conditioning Mode
The ICS1702 can enter a conditioning mode which applies a C/10
charge for a timed 10 hour period, followed by an indefinite C/40
maintenance charge until the batteries are removed.
The conditioning mode can be entered by setting the AUX0 pin
high (H) and the AUX1 pin open (Z). The SEL0 and SEL1 pins
must be set based on the charging current and the battery capacity.
The formula
gives the charge rate. Use Table 4 to find the correct SEL0 and
SEL1 settings. The MMN indicator will be active during the 10
hour conditioning charge and the maintenance charge that follows.
The ICS1702 enters the polling detect mode if the battery is
removed.
Ten Hour Timer Mode
Placing the AUX0 and AUX1 pins both high (H) enables a ten
hour timer. This timer limits the total charge, including the
maintenance charge, to approximately ten hours for a battery that is
completely discharged before fast charge is initiated. The ten hour
limit is based on the assumption that the charge terminates due to
the fast charge timer as shown in Table 2
Charge Rate
1.3 C
C/1.5
C/2.5
4 C
2 C
1 C
C/2
C/3
C/4
Battery Capacity (Amp hr)
Battery Capacity (Amp hr)
Charging Current (Amps)
Charging Current (Amps)
Fast Charge Timer Cutoff
Table 2: Ten Hour Timer Information
1.2 hrs
1.8 hrs
2.4 hrs
0.3 hrs
0.6 hrs
0.9 hrs
3.5 hrs
4.0 hrs
4.6 hrs
10
Charging System Test
The system test mode is intended for use in applications where the
charging system functionality needs to be tested. The system test
sequence consists of a one second activation of the CMN, MMN
and PFN indicator pins as well as the CHG and DCHG lines. The
OTN indicator is not activated. The system test mode is entered by
placing both the AUX0 and AUX1 pins low (L). The ICS1702
shuts down after the test sequence is finished and a master reset
must be performed to reactivate the device.
Cold Battery Charging
Cold battery charging is activated if a voltage at the THERM pin is
in the cold battery voltage range, as shown in Figure 9. The
ICS1702 checks for a cold battery before initiating fast charge. If a
cold battery is present before fast charge begins, the ICS1702
begins a two-hour C/10 topping charge (the pulsed duty cycle is
based on the selected charge rate). If the battery is still cold after
the two hour topping charge is complete, the ICS1702 begins a
C/40 maintenance charge. The maintenance charge will continue
for as long as the battery remains cold Unless the ten hour time
mode is selected. The thermistor voltage at the THERM pin is
checked every second to see if the battery has warmed up. If so, the
ICS1702 stops the topping or maintenance charge and begins a fast
charge at a rate selected by the SEL0 and SEL1 inputs. A cold
battery does not interfere with the condition mode, direct
maintenance mode, the discharge portion of the discharge-to-
charge mode, or the discharge-only mode as programmed by the
AUX0 and AUX1 pins. See the section on Temperature Sensing,
for more information.
The MMN and OTN indicators will be active, indicating that a low
current charge is being applied to a battery that is outside the
specified temperature range for fast charging. If the CMN and
OTN indicators are active see the Application Information section.
(after fast charge termination)
Maintenance Timer Cutoff
9.7 hrs
9.4 hrs
9.1 hrs
8.8 hrs
8.2 hrs
7.6 hrs
6.5 hrs
6.0 hrs
5.4 hrs
Charge Time Limit
(from reset)
10 hrs
10 hrs
10 hrs
10 hrs
10 hrs
10 hrs
10 hrs
10 hrs
10 hrs