LM3813M-1.0/NOPB National Semiconductor, LM3813M-1.0/NOPB Datasheet - Page 13

• Manufacturer Part Number: LM3813M-1.0/NOPB
• Description: IC CURRENT GAUGE PREC 8-SOIC
• Manufacturer: National Semiconductor
• Type: Battery Chargerr

Specifications of LM3813M-1.0/NOPB

• Function: Current Gauge
• Sensing Method: Low-Side
• Accuracy: ±2%
• Voltage - Input: 2 ~ 5.25 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Output Current: 1mA
• Operating Supply Voltage (min): 2V
• Operating Supply Voltage (max): 2.25V
• Operating Temp Range: -40C to 125C
• Package Type: SOIC N
• Mounting: Surface Mount
• Pin Count: 8
• Operating Temperature Classification: Automotive
• For Use With: LM3813EVAL - EVALUATION BOARD FOR LM3813
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Compliant
• Other names: *LM3813M-1.0; *LM3813M-1.0/NOPB; LM3813M-1.0

Timing Diagram
Duty cycle of the PWM waveform during any sampling interval indicates the current magnitude (average) and direction during the previous sampling interval.
*Maximum Sense Current = 1.0 Amps for LM3812-1.0 and LM3813-1.0.
The sense current should be multiplied by 10 for LM3812-7.0 and LM3813-7.0.
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
(%)
FIGURE 9. Typical Timing Diagram for Mostly Positive Current
TABLE 2. Duty Cycle to Current Conversion Table
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
13
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
Sense Current
(Amps)
-0.000
-0.055
-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
-0.110
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