gin can also be improved by adding C

in the section. The equation for A

additional equations required for the calculation:

mc ) 0.072fs (in V/s)

where R

mum input voltage, g

tance found in the Electrical Characteristics table, and R

D-

SON

is the value chosen from the graph "R

the Typical Performance Characteristics section.

LAYOUT CONSIDERATIONS

The input bypass capacitor C

operating circuit, must be placed close to the IC. This will

reduce copper trace resistance which effects input voltage

ripple of the IC. For additional input voltage filtering, a 100nF

bypass capacitor can be placed in parallel with C

the V

output capacitor, C

IC. Any copper trace connections for the C

increase the series resistance, which directly effects output

voltage ripple. The feedback network, resistors R

R

inductor, to minimize copper trace connections that can in-

ject noise into the system. Trace connections made to the

inductor and schottky diode should be minimized to reduce

power dissipation and increase overall efficiency. For more

detail on switching power supply layout considerations see

Application Note AN-1149: Layout Guidelines for Switching

Power Supplies.

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