LM3814 Datasheet, PDF (13/14 Pages) National Semiconductor (TI) – Fast Current Gauge IC with Ultra Low Loss Sense Element and PWM Output

Look-Up Tables (Continued)
TABLE 2. Duty Cycle to Current Conversion Table
Duty Cycle
(%)
95.5
92.5
90.0
87.5
85.0
82.5
80.0
77.5
75.0
72.5
70.0
67.5
65.0
62.5
60.0
57.5
55.0
52.5
50.0
Sense Current
(Amps)
0.990
0.935
0.880
0.825
0.770
0.715
0.660
0.605
0.550
0.495
0.440
0.385
0.330
0.275
0.220
0.165
0.110
0.055
0.000
Duty Cycle
(%)
50.0
47.5
45.0
42.5
40.0
37.5
35.0
32.5
30.0
27.5
25.0
22.5
20.0
17.5
15.0
12.5
10.0
7.5
5.0
*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.
Timing Diagram
Sense Current
(Amps)
-0.000
-0.055
-0.110
-0.165
-0.220
-0.275
-0.330
-0.385
-0.440
-0.495
-0.550
-0.605
-0.660
-0.715
-0.770
-0.825
-0.880
-0.935
-0.990
DS101013-11
Duty cycle of the PWM waveform during any sampling interval indicates the current magnitude (average) and direction during the previous sampling interval.
FIGURE 9. Typical Timing Diagram for Mostly Positive Current
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