cui.com

date

11/01/2012 │ page 4 of 5

CUI Inc

│ SERIES: VWRAT2 │ DESCRIPTION: DC-DC CONVERTER

1.

Requirement on Output Load

In order to ensure the product operates efficiently and reliably, make sure the specified range of input voltage is not exceeded and

the minimum output load is not less than 10% load. If the actual load is less than the specifi ed minimum load, the output ripple may

increase sharply while its effi ciency and reliability will reduce greatly. If the actual output power is very small, please add an

appropriate resistor as extra loading.

2.

Recommended Circuit

All VWRBT2 converters have been tested according to the following recommended testing circuit before leaving the factory. This

series should be tested under load, never under no load (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).

General:

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

5.

Solderability

reflow soldering, 240°C max.

Vin

GND

+Vo

0V

Cin

Cou t

DC

DC

-Vo

Cou t

Vout

(Vdc)

Cout

(μF)

±5

680

±9

470

±12

330

±15

220

Table 1

APPLICATION NOTES

Input Voltage (V)

Inp ut Voltage

Ra nge

Ip

Figure 1

Cin

12 V

24, 48 V

100 μF

10 ~ 47 μF

Cout

10 μF / 100 mA