cui.com

CUI Inc

│ SERIES: VWRAS2 │ DESCRIPTION: DC-DC CONVERTER

date 02/19/2013

│ page 4 of 5

1. CTRL Terminal

When open or high impedance,the converter work well; When this pin is ‘high’; the converter shutdown; It should be note that the

input current (Ic) should between 5-10mA, exceeding the maximum 20mA will cause permanence damage to the converter. The value

of R Can be derived as follows :

2. Recommended Circuit

If you want to further decrease the input/output ripple, an “LC” filtering network may be connected to the input and output ends of

the DC/DC converter, see (Figure 1).

However, the capacitance of the output filter capacitor must be proper. If the capacitance is too big, a startup problem might arise.

For every channel of output, provided the safe and reliable operation is ensured, the greatest capacitance of its filter capacitor sees

(Table 1).

3. Input Current

While using unstable power source, please ensure the output voltage and ripple voltage do not excced indexes of the converter. The

preceding power source must be able to provide for converter sufficient starting current Ip.

General: Ip ≤1.4*Iin-max

4. No parallel connection or plug and play

+Vo

0V

Cout

6

8

7

Cout

Lout

Lout

-Vo

Cin

Vin

GND

2

1

3

Vc

R

Lin

Ic

D1

Vin

(Vdc)

Cout

(µF)

±5

560

±9

470

±12

330

±15

270

±24

100

Table 1

APPLICATION NOTES

InputVoltage (V)

InputVoltage

Range

Ip

R=

V

I

C

Figure 1

Cin

5, 12 V

24, 48 V

100 µF

10 ~ 22 µF

Lin

--

4.7 ~ 120 µH

Cout

--

100 µF (typ)

Lout

--

2.2 ~ 10 µH