Configuration

These boards have the following characteristics:

I

Supply connector J1 accepts a maximum of 16VDC

(See the limitation on power dissipation below.)

I

Charge begins after application of both of the fol-

lowing:

–

the battery

–

supply voltage

I

Temperature sensing: disabled

I

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 0.2

Ω. 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