User Manual
Table Of Contents
- LM3812/LM3813
- General Description
- Key Specifications
- Features
- Applications
- Connection Diagrams
- Ordering Information
- Pin Description (High-Side, LM3812)
- Pin Description (Low-Side, LM3813)
- Absolute Maximum Ratings
- Operating Ratings
- Electrical Characteristics
- Typical Performance Characteristics
- Typical Application Circuits
- FIGURE 1. High Side Sense
- FIGURE 2. Low Side Sense
- FIGURE 3. Paralleling LM3812 for Higher Load Current ITOTAL = 2.2(D1-0.5)IMAX + 2.2(D2-0.5)IMAX
- FIGURE 4. High Voltage Operation - VIN Greater Than 5.25V (High Side Sense) (PWM output is referr
- FIGURE 5. High Voltage Operation - VIN Greater Than 5.25V (Low Side Sense)
- Product Operation
- PWM Output and Current Accuracy
- Look-Up Tables
- TABLE 2. Duty Cycle to Current Conversion Table
- Timing Diagram
- Physical Dimensions
Typical Performance Characteristics Supply bypass capacitor is 0.1 µF and filter capacitor is
0.1 µF. (Continued)
Current vs Duty Cycle Accuracy vs Supply Voltage
10012222
10012228
Accuracy vs Temperature (LM3812-1.0 and LM3813-1.0) Accuracy vs Temperature (LM3812-7.0 and LM3813-7.0)
10012229 10012230
Error vs Current (LM3812-1.0 and LM3813-1.0)
(Note 10)
Error vs Current (LM3812-7.0 and LM3813-7.0)
(Note 10)
10012227
10012231
Note 10: These curves represent a statistical average such that the noise is
insignificant.
LM3812/LM3813
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