LM3401EVAL National Semiconductor, LM3401EVAL Datasheet - Page 12

• Manufacturer Part Number: LM3401EVAL
• Description: BOARD EVALUATION FOR LM3401
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM3401EVAL

• Current - Output / Channel: 1A
• Outputs And Type: 1, Non-Isolated
• Features: Dimmable
• Voltage - Input: 4.5 ~ 35V
• Utilized Ic / Part: LM3401
• Kit Contents: Board
• Svhc: No SVHC (15-Dec-2010)
• Kit Features: Hysteretic Control For Speed And
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Voltage - Output: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed

The SNS and HYS resistors should be placed close to their
respective pins and grounded close to the GND pin. An iso-
lated ground area shown as SGND in Figure 10 is recom-
mended for the SNS, HYS, and GND pin connections. The
two ground areas, GND and SGND, should be connected on
an inner or bottom layer. This connection is shown as two vias
in Figure 10.
A large, continuous ground plane can also be used, as long
as the input capacitor and catch diode ground area is some-
what isolated.
The HG trace should be kept as short as possible to minimize
inductance and gate ringing (See HG and PFET selection
30021440
section).
Finally, for accurate current limit sensing, the CS pin and ILIM
FIGURE 10. Example PCB Layout
resistor connections should be made at the PFET pads, via
separate traces.
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