SC410 SEMTECH [Semtech Corporation], SC410 Datasheet - Page 23

• Manufacturer Part Number: SC410
• Description: 3A EcoSpeed TM Step-Down Regulator with LDO and Ultrasonic Power Save
• Manufacturer: SEMTECH [Semtech Corporation]

Applications Information (continued)
FB and Other Analog Control Signals
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to AGND are done by wide copper traces or vias
down to AGND.
Connect PGND to AGND with a short trace or 0Ω
resistor. This connection should be as close to
the IC as possible.
The connection from the V
analog control circuitry must be routed from the
output capacitors and located on a quiet layer.
The traces between V
circuitry (AGND, and FB pins) must be as short as
possible. The traces must also be routed away
from noise sources, such as BST, LX, VIN, and
PGND between the input capacitors, output
capacitors, and the IC.
The TON node must be as short as possible to
ensure the best accuracy for the on time.
The feedback components for the switcher need
to be as close to the FB pin of the IC as possible
to reduce the possibility of noise corrupting
these analog signals.
OUT
and the analog control
OUT
power to the
BST and LX
Capacitors and Current Loops
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LX and BST are very noisy nodes and must be
carefully routed to minimized the PCB area that
is exposed to these signals.
The connections for the boost capacitor
between the IC and LX must be short and directly
connected to the LX (pin 3).
The LX node between the IC and the inductor
should be wide enough to handle the inductor
current and short enough to eliminate the pos-
sibility of LX noise corrupting other signals.
The current loops between the input capacitors,
the IC, the inductor, and the output capacitors
must be as close as possible to each other to
reduce IR drop across copper planes and traces.
All bypass and output capacitors must be con-
nected as close as possible to their respective
pin on the IC.
SC410
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