LM3813M-1.0/NOPB National Semiconductor, LM3813M-1.0/NOPB Datasheet - Page 12

• 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

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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
*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.
Sense Current
(Amps)*
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
0.55
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
TABLE 1. Current to Duty Cycle Conversion Table
Duty Cycle
95.5
93.2
90.9
88.6
86.4
84.1
81.8
79.5
77.3
75.0
72.7
70.5
68.2
65.9
63.6
61.4
59.1
56.8
54.5
52.3
50.0
(%)
12
quantization error of
Please see the “PWM Output and Current Accuracy” section
for more details.
Sense Current
(Amps)*
-1.00
-0.95
-0.90
-0.85
-0.80
-0.75
-0.70
-0.65
-0.60
-0.55
-0.50
-0.45
-0.40
-0.35
-0.30
-0.25
-0.20
-0.15
-0.10
-0.05
-0.00
1
⁄
2
bit is not shown in these tables.
Duty Cycle
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
11.4
(%)
4.5
6.8
9.1