Table 2. duty cycle to current conversion table, Timing diagram – Rainbow Electronics LM3815 User Manual
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TABLE 2. DUTY CYCLE TO CURRENT CONVERSION TABLE
Duty Cycle
(%)
Sense Current
(Amps)
Duty Cycle
(%)
Sense Current
(Amps)
95.5
0.990
50.0
-0.000
92.5
0.935
47.5
-0.055
90.0
0.880
45.0
-0.110
87.5
0.825
42.5
-0.165
85.0
0.770
40.0
-0.220
82.5
0.715
37.5
-0.275
80.0
0.660
35.0
-0.330
77.5
0.605
32.5
-0.385
75.0
0.550
30.0
-0.440
72.5
0.495
27.5
-0.495
70.0
0.440
25.0
-0.550
67.5
0.385
22.5
-0.605
65.0
0.330
20.0
-0.660
62.5
0.275
17.5
-0.715
60.0
0.220
15.0
-0.770
57.5
0.165
12.5
-0.825
55.0
0.110
10.0
-0.880
52.5
0.055
7.5
-0.935
50.0
0.000
5.0
-0.990
*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
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
LM3814/LM3815
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