Look-Up Tables

The following tables show how to convert the duty cycle of

the PWM output to a current value, and vice versa. The

Please see the “PWM Output and Current Accuracy” section

for more details.

TABLE 1. Current to Duty Cycle Conversion Table

Sense Current

Duty Cycle

(%)

Sense Current

Duty Cycle

(%)

1.00

95.5

-1.00

4.5

0.95

93.2

-0.95

6.8

0.90

90.9

-0.90

9.1

0.85

88.6

-0.85

11.4

0.80

86.4

-0.80

13.6

0.75

84.1

-0.75

15.9

0.70

81.8

-0.70

18.2

0.65

79.5

-0.65

20.5

0.60

77.3

-0.60

22.7

0.55

75.0

-0.55

25.0

0.50

72.7

-0.50

27.3

0.45

70.5

-0.45

29.5

0.40

68.2

-0.40

31.8

0.35

65.9

-0.35

34.1

0.30

63.6

-0.30

36.4

0.25

61.4

-0.25

38.6

0.20

59.1

-0.20

40.9

0.15

56.8

-0.15

43.2

0.10

54.5

-0.10

45.5

0.05

52.3

-0.05

47.7

0.00

50.0

-0.00

50.0

The sense current should be multiplied by 10 for LM3812-7.0 and LM3813-7.0.

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