Rev A

RBA30 SERIES

30 Watts

DC/DC Converter

Single & Dual Output

11/21/2017

Wall Industries, Inc. • 37 Industrial Drive, Exeter, NH 03833 • Tel: 603-778-2300 • Toll Free: 888-597-9255 •

Fax 603-778-9797

website: www.wallindustries.com • e-mail: sales@wallindustries.com

Page 9 of 10

DESIGN REFERENCE

1. Typical Application

All the DC/DC converters of this series are tested below according to the recommended circuit below. If it is required to further reduce input and output

ripple, properly increase the input & output of additional capacitors Cin and Cout or select capacitors of low equivalent impedance provided that the

capacitance is no larger than the max. capacitive load of the product.

Single Output

Voltage (VDC)

Cout

(µF)

Cin

(µF)

Dual Output

Voltage (VDC)

Cout

(µF)

Cin

(µF)

3.3/5/9

220

100

±5/±12/±15

220

100

12/15/24

100

±24

100

2. EMC Solution-Recommended Circuit

Note: Part

①inthefigureaboveisusedforEMStestandpart②forEMI

filtering; selected based on needs.

Parameter Description

Model

24Vin

48Vin

FUSE

Choose according to actual input current

MOV

S20K30

S14K60

C0

680µF/50V

330µF/100V

C1

330µF/50V

330µF/100V

C2

4.7µF/50V

2.2µF/100V

C3

Refer to Cout in Typical Application Figure

LCM

1mH, contact factory for recommendation

CY1, CY2

1nF/2KV

Notes: Part

①inthefigureaboveisusedforEMStestandpart②forEMI

filtering; selected based on needs.

Parameter Description

Model

24Vin

48Vin

FUSE

Choose according to actual input current

MOV

S20K30

S14K60

C0

680µF/50V

330µF/100V

C1

2.2µF/50V

2.2µV/100V

C2

2.2µF/50V

2.2µF/100V

C3

330µF/50V

330µF/100V

C4

Refer to Cout in Typical Application Figure

LDMI

3.3µH

CY1, CY2

2.2nF/400VAC Safety Y Capacitor

3. Application of Trim and Calculation of Trim Resistance

Applied circuit of Trim (part in broken line is the interior of models)

Calculation formula of Trim resistance:

a=

Vref

∙R

1

Vo’-Vref

a=

Vo’-Vref

∙R

2

Vref

Vo’ for the actual needs of the up or down regulated votlage

Vout (VDC)

R1 (KΩ)

R2 (KΩ)

R3 (KΩ)

Vref(V)

3.3

4.801

2.87

12.4

1.24

5

2.883

2.87

10

2.5

9

7.500

2.87

15

2.5

12

11.000

2.87

15

2.5

15

14.494

2.87

15

2.5

24

24.872

2.87

17.8

2.5

4. Models cannot be connected in parallel to increase power.