LM8801TME-1.82 NSC [National Semiconductor], LM8801TME-1.82 Datasheet - Page 13

• Manufacturer Part Number: LM8801TME-1.82
• Description: High Precision 6MHz, 600 mA Synchronous Step-Down DC-DC Converter for Mobile Applications
• Manufacturer: NSC [National Semiconductor]

5.
6.
7.
Use wide traces between the power components and for
power connections to the DC-DC converter circuit. This
reduces voltage errors caused by resistive losses across
the traces.
Route noise sensitive traces such as the voltage
feedback path away from noisy traces between the
power components. The voltage feedback trace must
remain close to the LM8801 circuit and should be routed
directly from FB to V
should be routed opposite to noise components. This
reduces EMI radiated onto the DC-DC converter’s own
voltage feedback trace.
Place noise sensitive circuitry, such as radio IF blocks,
away from the DC-DC converter, CMOS digital blocks
OUT
at the output capacitor and
13
In mobile phones, for example, a common practice is to place
the DC-DC converter on one corner of the board, arrange the
CMOS digital circuitry around it (since this also generates
noise), and then place sensitive preamplifiers and IF stages
on the diagonally opposing corner. Often, the sensitive cir-
cuitry is shielded with a metal pan and power to it is post-
regulated to reduce conducted noise, using low-dropout
linear regulators.
and other noisy circuitry. Interference with noise-
sensitive circuitry in the system can be reduced through
distance.
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