Datasheet

Configuration
These boards have the following characteristics:
■
Supply connector J1 accepts a maximum of 16VDC
(See the limitation on power dissipation below.)
■
Charge begins after application of both of the fol
-
lowing:
–
the battery
– supply voltage
■
Temperature sensing: disabled
■
AutoComp: disabled
The on-board regulator supplies a charging current of
500mA. This current is controlled by the value of the
sense-resistor, R2 in the following equation:
I
0.100
R
CHG
2
=
As configured, charge can be inhibited by connecting the
INH input to DC+ or DC–.
The value of R2 at shipment is 0.2Ω. This resistor can be
changed to suit the application. However, the maximum
power dissipation in Q1 should not exceed the PD rat
-
ing. (See recommended DC Operating Conditions.)
Setup Procedure
1. Connect the battery pack to J1.
2. Connect the charging supply to J2.
See the bq2057 data sheet for information on configur
-
ing the temperature sensing circuit and the AutoComp
feature.
As shipped the DV2057/C/T/W uses a bipolar transistor
(Q1). Optionally, the user may replace Q1 with a
P-channel MOSFET. Please refer to the schematic for
details.
2
DV2057/C/T/W
Part Number Regulation Voltage
DV2057 4.1V
DV2057C 4.2V
DV2057T 8.2V
DV2057W 8.4V
DV2057/C/T/W Regulation Voltages