8

Rev.1.3

11 -

9. PCB layout guide

PCB layout is very important to achieve stable operation. Please follow the guidelines below.

1) Keep the path of switching current short and minimize the loop area formed by Input capacitor, high-side

MOSFET and low-side MOSFET.

2) Bypass ceramic capacitors are suggested to be put close to the VIN Pin.

3) Ensure all feedback connections are short and direct. Place the feedback resistors and compensation

components as close to the chip as possible.

4) Rout SW away from sensitive analog areas such as FB.

5) Connect IN, SW, and especially GND respectively to a large copper area to cool the chip to improve

thermal performance and long-term reliability.

SOP-8

■Marking

LV1482SN

a b c d e f

g h i j k

Mark

Content

LV1482SN

Product ID

a to k

Assembly lot No.:

0 to 9 & A to Z repeated

L

R1

R2

R3

Cout

C1

Vout=5.0V

10µH

15K

15K

6.8K

16K

22µF

3.3nF

Vout=3.3V

10µH

12K

100

4.7K

15K

22µF

3.3nF

Vout=2.5V

10µH

9.1K

470

5.6K

13K

22µF

3.3nF

Vout=1.8V

10µH

6.8K

1K

8.2K

6.8K

22µF

3.3nF

Vout=1.2V

4.7µH

1.5K

1.5K

10K

5.1K

22µF

3.3nF

Vout=1.0V

3.3µH

1K

1K

24K

4.7K

22µF

3.3nF

Table2 : BOM of ELM613DA

when Vin≤ 6V, for the purpose of promote the efficiency, it can add an external Schottky diode between IN and

BS pins, as shown in Figure 2.

SW

BS

GND

VIN

ELM613DA

Schottky

(B0520LW)

5V to 6V

Vout

▲

Figure 2: Add a Schottky diode to promote efficiency when Vin ≤ 6V.