LM3478MM National Semiconductor, LM3478MM Datasheet - Page 20

• Manufacturer Part Number: LM3478MM
• Description: Pulse Width Modulation (PWM) Controller IC
• Manufacturer: National Semiconductor

Specifications of LM3478MM

• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Mounting Type: Surface Mount
• Features: High Efficiency
• Package / Case: 8-MSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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Output Capacitor Selection
the output for high efficiency and low ripple voltage. Surface
mount tantalums, surface mount polymer electrolytic and
polymer tantalum, Sanyo- OSCON, or multi-layer ceramic
capacitors are recommended at the output.
The output capacitor of the SEPIC sees very large ripple
currents (similar to the output capacitor of a boost converter.
The rms current through the output capacitor is given by:
The ESR and ESL of the output capacitor directly control the
output ripple. Use low capacitors with low ESR and ESL at
the output for high efficiency and low ripple voltage. Surface
Other Application Circuit
(Continued)
FIGURE 13. Typical Flyback Circuit
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mount tantalums, surface mount polymer electrolytic and
polymer tantalum, Sanyo- OSCON, or multi-layer ceramic
capacitors are recommended at the output for low ripple.
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