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)
PWM Frequency vs Supply Voltage PWM Frequency vs Temperature
10012213
10012216
Operating Current vs Supply Voltage Shutdown Current vs Supply Voltage
10012218 10012219
Operating Current vs Temperature Shutdown Current vs Temperature
10012220 10012221
LM3812/LM3813
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