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circuit rent rating for the diode should be equal to the maximum output current for best reliability in most applications.

In cases where the input voltage is much greater than the output voltage the average diode current is lower. In this

case it is possible to use a diode with a lower average current rating, approximately (1-D)Io, however the peak

current rating should be higher than the maximum load current 0.5A to 1A rated diode is a good starting point.

Layout Considerations

To reduce problems with conducted noise pick up, the ground side of the feedback network should be connected

directly to the GND pin with its own connection. The feedback network, resistors R1 and R2, should be kept close to

the FB pin, and away from the inductor to minimize coupling noise into the feedback pin. The input bypass capacitor

the IC. The inductor L should be placed close to the SW pin to reduce magnetic and electrostatic noise. The output

capacitor, Co should be placed close to the junction of L and the diode D1. The L, D1, and Co trace should be as

short as possible to reduce conducted and radiated noise and increase overall efficiency. The ground connection for

(preferably at the Co ground point) to minimize conducted noise in the system ground plane.

Typical Performance Characteristics

T =25°C, unless otherwise noted.