AN3233

Harmonic content measurement

Doc ID 17595 Rev 1

13/35

3

Harmonic content measurement

The board has been tested according to the European standard EN61000-3-2 Class-D and

the Japanese standard JEITA-MITI Class-D, at both the nominal input voltage mains. As

shown in the following images, the circuit is able to reduce the harmonics well below the

limits of both regulations.

Figure 5.

Compliance with EN61000-3-2 at 230 Vac – 50 Hz, full load

THD = 14.70 % - PF = 0.978

Figure 6.

Compliance with JEITA-MITI at 100 Vac – 50 Hz, full load

THD = 5.20 % - PF = 0.995

On the bottom side of the diagrams the total harmonic distortion (THD) and power factor

(PF) have been measured too. The values in all conditions give a clear idea regarding the

correct functioning of the PFC.

0.1

1

Measured Value

EN610003 2 ClassD Limits

0.0001

0.001

0.01

0.1

1

1

3

579

11 13 15 17 19 21 23 25 27 29 31 33 35 37 39

Harmonic Order [n]

0.1

1

Measured Value

JEITAMITI Class D Limits

0.0001

0.001

0.01

0.1

1

1

3

57

9

11 13 15 17 19 21 23 25 27 29 31 33 35 37 39

Harmonic Order [n]