DC/DC Converter

K78xx-500R3 Series

2016.11.01-A/2

Page 3 of 4

MORNSUN Guangzhou Science & Technology Co., Ltd. reserves the copyright and right of final interpretation

Design Reference

1. Typical application circuit

+Vin

GND

GND

DC/DC

1

2

3

+Vout

C1

C2

Positive output application circuit

+Vin

GND

GND

DC/ DC

1

2

3

-Vout

C1

C2

Negative output application circuit

Fig. 2 Typical application circuit

1

3

2

+Vin

GND

-Vout

C2

GND

DC/DC

1

2

3

+Vout

C1

C3

C4

LDM

DC/DC

Fig. 3 Positive and Negative output parallelling application circuit

Sheet 1

Part No.

C1/C3

(ceramic capacitor)

C2/C4

(ceramic capacitor)

K7803-500R3

10μF/50V

22μF/10V

K7805-500R3

22μF/10V

K7809-500R3

22μF/16V

K7812-500R3

22μF/25V

K7815-500R3

22μF/25V

Note:

1. C1 and C2 (C3 and C4) are required and should be connected close to the pin terminal of the module.

2. The capacitance of C1 and C2 (C3 and C4) refer to Sheet 1, it can be increased properly if required, and tantalum or low ESR electrolytic capacitors may

also suffice.

3. When the products used as the circuit like figure 3, an inductor named as LDM up to 10μH is recommended in the circuit to reduce the mutual interference.

4. Cannot be used in parallel for output and hot swap.

To reduce the output ripple furtherly, it is suggested to connect a “LC” filter at the output terminal, and recommended value of L is

10µH-47µH.

3

+Vin

GND

Vout

1

负

载

DC/DC

C1

22 F

μ

2

C2

L

Positive output

2

+Vin

GND

Vout

1

负

载

DC/DC

C1

22 F

μ

3

C2

L

Negative output

Fig. 4 “LC” filter application circuit

2. EMC solution-recommended circuit

DC/DC

Vin

LDM2

②

C0

LDM1

MOV

FUSE

①

C5

V in

GN D

+

+Vo

GN D

LOAD

C2

C1

Fig. 5 EMC recommended circuit