to minimize copper trace connections that can inject noise

into the system. The ground connection for the current set-

ting resistor should connect directly to the GND pin. The

AGND pin should connect directly to the GND pin. Not

connecting the AGND pin directly, as close to the chip as

possible, may affect the performance of the LM3501 and

limit its current driving capability. Trace connections made to

the inductor should be minimized to reduce power dissipa-

tion, EMI radiation and increase overall efficiency. It is good

practice to keep the V

such as the FB pin. Failure to do so may inject noise into the

FB pin and affect the regulation of the device. See Figure 3

and Figure 4 for an example of a good layout as used for the

LM3501 evaluation board.

20065384

FIGURE 3. Evaluation Board Layout (2X Magnification)

Top Layer

20065385

FIGURE 4. Evaluation Board Layout (2X Magnification)

Bottom Layer (as viewed from the top)

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