NXP Semiconductors
PF4210
14-channel power management integrated circuit (PMIC) for audio/video applications
12.2 Component placement
It is desirable to keep all components related to the power stage as close to the PMIC as
possible, especially decoupling input and output capacitors.
12.3 General routing requirements
• Some recommended things to keep in mind for manufacturability:
– Via in pads require a 4.5 mil minimum annular ring. Each pad must be 9.0 mils larger
than its hole
– Maximum copper thickness for lines less than 5.0 mils wide is 0.6 oz copper
– Minimum allowed spacing between line and hole pad is 3.5 mils
– Minimum allowed spacing between line and line is 3.0 mils
• Care must be taken with SWxFB pins traces. These signals are susceptible to noise
and must be routed far away from power, clock, or high-power signals, like the ones on
the SWxIN, SWx, SWxLX, SWBSTIN, SWBST, and SWBSTLX pins. They could also
be shielded.
• Shield feedback traces of the regulators and keep them as short as possible (trace
them on the bottom so the ground and power planes shield these traces).
• Avoid coupling traces between important signal/low-noise supplies (like REFCORE,
VCORE, VCOREDIG) from any switching node (for example, SW1ALX, SW1BLX,
SW1CLX, SW2LX, SW3ALX, SW3BLX, SW4LX, and SWBSTLX).
• Make sure that all components related to a specific block are referenced to the
corresponding ground.
12.4 Parallel routing requirements
• I2C signal routing
– CLK is the fastest signal of the system, therefore it must be given special care.
– To avoid contamination of these delicate signals by nearby high-power or high-
frequency signals, it is a good practice to shield them with ground planes placed on
adjacent layers. Make sure the ground plane is uniform throughout the entire signal
trace length.
DO
Signal
DON'T
Signal
Ground plane
Ground planes
aaa-023891
– These signals can be placed on an outer layer of the board to reduce their
capacitance with respect to the ground plane.
– Care must be taken with these signals not to contaminate analog signals, as they are
high-frequency signals. Another good practice is to trace them perpendicularly on
different layers, so there is a minimum area of proximity between signals.
PF4210
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© NXP B.V. 2018. All rights reserved.
Data sheet: technical data
Rev. 2.0 — 14 November 2018
128 / 137
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