LM3814_05 Datasheet, PDF (13/14 Pages) National Semiconductor (TI) – Fast Current Gauge IC with Ultra Low Loss Sense Element and PWM Output

TABLE 2. DUTY CYCLE TO CURRENT CONVERSION TABLE
Duty Cycle
Sense Current
Duty Cycle
(%)
(Amps)
(%)
95.5
0.990
50.0
92.5
0.935
47.5
90.0
0.880
45.0
87.5
0.825
42.5
85.0
0.770
40.0
82.5
0.715
37.5
80.0
0.660
35.0
77.5
0.605
32.5
75.0
0.550
30.0
72.5
0.495
27.5
70.0
0.440
25.0
67.5
0.385
22.5
65.0
0.330
20.0
62.5
0.275
17.5
60.0
0.220
15.0
57.5
0.165
12.5
55.0
0.110
10.0
52.5
0.055
7.5
50.0
0.000
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.
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
Timing Diagram
10101311
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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