LM3519 Datasheet, PDF (13/14 Pages) National Semiconductor (TI) – High Frequency Boost White LED Driver with High-Speed PWM Brightness Control

Application Information (Continued)
I_OUT vs V_IN
LAYOUT GUIDELINES
The input capacitor, C_IN, must be placed close to the
LM3519. Placing C_IN close to the device will reduce the
metal trace resistance effect on input voltage ripple. Metal
trace connections for the C_OUT capacitor can increase the
effective series resistance, which affects output voltage
ripple and efficiency. Trace connections to the inductor
should be short and wide to reduce power dissipation, in-
crease overall efficiency and reduce EMI radiation. The di-
ode, like the inductor, should have trace connections that are
short and wide to reduce power dissipation and increase
overall efficiency. For more details regarding layout guide-
lines for switching regulators, refer to Applications Note AN-
1149.
20160239
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