AN2359

Layout considerations

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5

Layout considerations

A proper PCB layout is essential for correct operation of any switch-mode converter and the

same basic rules have to be taken into account in order to optimize the current path,

especially in high current path routing.

Since EMI issues are related to layout, the current loop area has to be minimized. Moreover,

the control ground path has to be separated from power ground, in order to avoid any noise

interference between the control section and the power section.

All the traces carrying high currents have to be as short as possible, in order to minimize the

resistive and inductive effect.

A particular care has to be taken into account regarding the optimal routing of the input EMI

bulk capacitors, trace as short as possible…).

Table 11.

η[%]

0

0

24.16

5.098

0.513

0.21

0.00

0.00

10

30

23.99

5.094

1.852

0.74

0.39

53.01

50

150

24

5.094

7.04

2.82

1.96

69.75

80

240

24.03

5.085

10.66

4.26

3.14

73.71

100

300

24.028

5.071

13.14

5.26

3.92

74.66

0

300

41

5.03

6.68

2.67

1.51

56.47

100

0

21.93

5.1

7.221

2.89

2.19

75.92

Figure 16.

full load: commutation

Figure 17.

full load: detail