Pcb Layout Guide; Component Layout Order; Dc/Dc Circuit Components Placement & Layout - Realtek RTL8762C Hardware Instructions

13 PCB Layout Guide

13.1 Component Layout Order

Arranging the components should follow the order below. The higher priority indicates that the
component should be closer to IC.
1. DC/DC circuit components
2. VBAT bypass capacitor
3. RF circuit components
4. 40MHz Crystal
5. RF VDD bypass capacitor
6. Other bypass capacitors
13.2 DC/DC Circuit Components Placement & Layout
The input power trace connected to HVD/VBAT must be as wide as possible; it's
1.
recommended to be 20 or 25mil.
2. The inductor of switching regulator (buck) and capacitor is suggested to be close to BT
chip.
3. The switching regulator power pin LX goes through the2.2uH inductor and a 4.7uF
capacitor to form a stable, low noise power source. It is strictly prohibited to pull out the
power without going through the 4.7uF capacitor (like the yellow line in the figure
below). The trace of LX should be short and wide for the consideration of EMI issue; the
trace width is suggested to be at least 15mil.
4. The ground terminal of the 4.7uF
shorten the ground loop. If the space is sufficient, place more ground via around the
ground pin of 4.7uF
capacitor should be close to the chip's
capacitor.
RTL8762C Evaluation Board User Manual
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