LM3526-L NSC [National Semiconductor], LM3526-L Datasheet - Page 9

• Manufacturer Part Number: LM3526-L
• Description: Dual Port USB Power Switch and Over-Current Protection
• Manufacturer: NSC [National Semiconductor]

Application Information
PCB LAYOUT CONSIDERATIONS
In order to meet the USB requirements for voltage drop,
droop and EMI, each component used in this circuit must be
evaluated for its contribution to the circuit performance. The
PCB layout rules and guidelines must be followed.
• Place the switch as close to the USB connector as pos-
sible. Keep all V
least 50-mil, 1 ounce copper for all V
plating the traces will reduce the trace resistance.
bus
traces as short as possible and use at
FIGURE 2. Self-Powered Hub Per-Port Voltage Drop
(Continued)
bus
traces. Solder
9
• Avoid vias as much as possible. If vias are used, use mul-
• Place the output capacitor and ferrite beads as close to
• If ferrite beads are used, use wires with minimum resis-
tiple vias in parallel and/or make them as large as pos-
sible.
the USB connector as possible.
tance and large solder pads to minimize connection re-
sistance.
DS101097-23
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