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 Application Circuits In the application circuits, the 0.1 µF ceramic capacitor between pins 1 and 8
is used for bypassing, and the 0.1 µF ceramic capacitor between pins 3 and 4 is used for filtering. Shutdown (SD) is tied to
V
DD
through a 10 kΩ resistor. (Continued)
10012208
FIGURE 4. High Voltage Operation — V
IN
Greater Than 5.25V (High Side Sense)
(PWM output is referred to Pin 7)
10012209
FIGURE 5. High Voltage Operation — V
IN
Greater Than 5.25V (Low Side Sense)
LM3812/LM3813
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