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5

Output Voltage Adjustment

Figure 3. Test and output voltage trim configuration

Parallel Configuration

Load

+S

+V

-V

-S

PC

+S

+V

-V

-S

PC

Figure 4. Parallel configuration for current sharing

Notes.

Up to 4 converters to share within 90% max power.

The trim pin permits the user to adjust the output voltage up or down

according to the trim range specification (40% to 110% of nominal

output). This is accomplished by connecting resistor Rv between the

Sense pins. The trim pin should be left open if trimming is not being

used. The trim resistor can be determined by the following equations:

The capacitor C1 is recommended to be low ESR and is to balance the line indunctance on the input of the DC/DC converter. For stable

operation, connect a low impedance electrolytic capacitor C2 in the output terminals. When operated at lower temperature than -20 °C,

increasing the C2 capacitance with three or four times more than the recommended value.

Rtrim: KΩ, 6.2 kΩ recommended

Vo: Nominal Output Voltage

: Variable Resistor, KΩ

(Vo + R ) x Vf

v

Vtrim =

Rtrim x 33

Rtrim + 33

1.24 x

Vf =

Rtrim x 33

Rtrim + 33

7.68 +

DC

C1

R1

+Vin

-Vin

+SNS

Rtrim

C2

Load

+Vout

-Vout

-SNS

TRIM

+On/Off

C1: 220 µF/100 V

C2: 470 µF/100 V

Low ESR electrolytic

capacitors are recommended

-On/Off

v