MR750 SERIES

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5

Figure 9. Rectification Efficiency

Figure 10. Reverse Recovery Time

REPETITION FREQUENCY (kHz)

2.0

1.0

100

50

30

20

70

3.0

5.0

100

70

7.0 10

20

30

50

CURRENT INPUT WAVEFORM

0.2

0.1

20

7.0

5.0

2.0

1.0

7.0

0.3

0.5

10

3.0

10

0.7 1.0

2.0

3.0

5.0

3 A

1 A

0

Figure 11. Junction Capacitance

Figure 12. Forward Recovery Time

1.0

3.0

500

300

200

100

70

50

2.0

10

20

100

7.0

5.0

50

30

1.0

0.7

0.5

0.3

0.2

0.1

2.0

5.0

3.0

1.0

7.0

10

30

700

1000

30

20

10

70

Figure 13. Single−Phase Half−Wave

Rectifier Circuit

The rectification efficiency factor

σ shown in Figure 9

was calculated using the formula:

σ +

+

R

L

.100%

+

.100%

(1)

lossless, the maximum theoretical efficiency factor becomes:

σ

.100% + 4

.100%

+ 40.6%

(2)

factor becomes:

σ

.100% + 50%

(3)

(A full wave circuit has twice these efficiencies)

As the frequency of the input signal is increased, the

reverse recovery time of the diode (Figure 10) becomes

significant, resulting in an increasing AC voltage

forward current, thereby reducing the value of the efficiency

factor

σ, as shown on Figure 9.

It should be emphasized that Figure 9 shows waveform

efficiency only; it does not provide a measure of diode

losses. Data was obtained by measuring the AC component

with a DC voltmeter. The data was used in Equation 1 to

obtain points for Figure 9.