Look-up tables – Rainbow Electronics LM3824 User Manual
Page 10
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
quantization error of
1
⁄
2
bit is not shown in these tables.
Please see the “PWM Output and Current Accuracy” section
for more details.
TABLE 1. Current to Duty Cycle Conversion Table
Sense Current
(Imax = 1.0A)
Sense Current
(Imax = 2.0A)
Duty Cycle (%)
1
2
95.5
0.95
1.90
93.2
0.90
1.80
90.9
0.85
1.70
88.6
0.80
1.60
86.4
0.75
1.50
84.1
0.70
1.40
81.8
0.65
1.30
79.5
0.60
1.20
77.3
0.55
1.10
75.0
0.50
1
72.7
0.45
0.90
70.5
0.40
0.80
68.2
0.35
0.70
65.9
0.30
0.60
63.6
0.25
0.50
61.4
0.20
0.40
59.1
0.15
0.30
56.8
0.10
0.20
54.5
0.05
0.10
52.3
0.00
0.00
50
−0.05
−0.10
47.7
−0.10
−0.20
45.5
−0.15
−0.30
43.2
−0.20
−0.40
40.9
−0.25
−0.50
38.6
−0.30
−0.60
36.4
−0.35
−0.70
34.1
−0.40
−0.80
31.8
−0.45
−0.90
29.5
−0.50
−1
27.3
−0.55
−1.10
25
−0.60
−1.20
22.7
−0.65
−1.30
20.5
−0.70
−1.40
18.2
−0.75
−1.50
15.9
−0.80
−1.60
13.6
−0.85
−1.70
11.4
−0.90
−1.80
9.1
−0.95
−1.90
6.8
−1
−2
4.5
LM3824
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