Output Capacitor Selection

(Continued)

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

mount tantalums, surface mount polymer electrolytic and

polymer tantalum, Sanyo- OSCON, or multi-layer ceramic

capacitors are recommended at the output for low ripple.

Other Application Circuit

10135543

FIGURE 13. Typical Flyback Circuit

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