lm2633mtd National Semiconductor Corporation, lm2633mtd Datasheet - Page 30

• Manufacturer Part Number: lm2633mtd
• Description: Advanced Two-phase Synchronous Triple Regulator Controller For Notebook Cpus
• Manufacturer: National Semiconductor Corporation

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Input Capacitor Selection
Control Loop Design
Samll Signal Model
The buck regulator small signal model is shown in Figure 7 .
The model is obtained by applying the current-controlled
PWM switch derived by Vorperian and by omitting portions
that are irrelevant in a buck topology.
FIGURE 6. Input Ripple RMS Current Ratio: 2-phase vs. In-phase
(Continued)
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In the model, the DC output conductance of the PWM switch
is:
FIGURE 7. Small Signal Model of Buck Regulators
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