LM3814_05 Datasheet, PDF (12/14 Pages) National Semiconductor (TI) – Fast Current Gauge IC with Ultra Low Loss Sense Element and PWM Output

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 ¹â„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
Duty Cycle
Sense Current
(Amps)*
(%)
(Amps)*
1.00
95.5
-1.00
0.95
93.2
-0.95
0.90
90.9
-0.90
0.85
88.6
-0.85
0.80
86.4
-0.80
0.75
84.1
-0.75
0.70
81.8
-0.70
0.65
79.5
-0.65
0.60
77.3
-0.60
0.55
75.0
-0.55
0.50
72.7
-0.50
0.45
70.5
-0.45
0.40
68.2
-0.40
0.35
65.9
-0.35
0.30
63.6
-0.30
0.25
61.4
-0.25
0.20
59.1
-0.20
0.15
56.8
-0.15
0.10
54.5
-0.10
0.05
52.3
-0.05
0.00
50.0
-0.00
*Maximum Sense Current = 1.0 Amps for LM3814-1.0 and LM3815-1.0
The sense current should be multiplied by 10 for LM3814-7.0 and LM3815-7.0.
Duty Cycle
(%)
4.5
6.8
9.1
11.4
13.6
15.9
18.2
20.5
22.7
25.0
27.3
29.5
31.8
34.1
36.4
38.6
40.9
43.2
45.5
47.7
50.0
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