Datasheet

Fixed Configuration
The DV2954S1L board has the following characteristics:
■
V
CC
for the fast-charge IC is regulated onboard
from the supply at connector J1.
■
J1 can accept a maximum of 24VDC.
■
LED indicates charge status.
■
Charge begins on the later application of
–
The battery
–
Supply voltage
The on-board regulator supplies a fast charge current
I
MAX
of 1.25A. The fast-charge voltage V
MAX
is set at
25°C.
The switching frequency of the PWM control loops is
120kHz.
The regulated current is controlled by the value of the
sense resistor R
SNS
according to the relationship
I
V
R
CHG
SNS
=
0 250.
The value of R
SNS
(R18 in the schematic) at shipment is
0.200
Ω
. This resistor can be changed depending on the
application. The maximum charging current I
MAX
for the
DV2954S1L board is 1.25A.
The thermistor provided is a Philips 2322–640–63103.
With this thermistor connected between TEM+ and
BAT-, the temperature fault limits are V
LTF
(low-tem
-
perature fault) = 0°C, V
HTF
(high-temperature fault) =
45°C, and V
TCO
(charge cutoff) = 47°C.
Jumper-Selectable Configuration
The DV2954S1L can be configured as follows (see Jum
-
ber Configuration Diagram for location of the jumbers):
JP1: Configures the display mode (DSEL).
JP2: Configures the board for the number of cells.
JP3: Sets the full and minimum current termination.
Setup Procedure
1. Connect the thermistor to TEM+ and BAT-.
2. Attach the battery pack to BAT+ and BAT-.
3. Connect the charging supply to J1.
The following table shows the minimum input require-
ment for a given number of cells.
The combined charging and system load should not ex
-
ceed the I
MAX
limit of 1.25A.
2
DV2954S1L
Rev. C Board
JP3 I
FULL
I
MIN
[1 2] 3
I
MAX
5
I
MAX
10
1 [2 3]
I
MAX
10
I
MAX
15
1 2 3
I
MAX
15
I
MAX
20
JP2 Number of Cells
[1 2 ] 3 4 5 6 7 8
1
1 2 [3 4] 5 6 7 8
2
1 2 3 4 [5 6] 7 8
3
1 2 3 4 5 6 [7 8]
4
JP1 Display Mode
[1 2 ] 3
Mode 1
1 [2 3]
Mode 2
1 2 3 Mode 3
Number of Cells
Minimum Charger
Supply Input
1 7.5VDC
2 12VDC
3 18VDC
4 23VDC