Universal Global Scientific Industrial Co. Ltd. VZ22Q Manual Do Utilizador
VZ22Q LTE Module
V0.1
USI
Confidential
Page 16 of 23
5. Audio Codec Layout Guide
(TBD)
To ensure maximum performance from the ALC5623 codec, Please refer to “Realtek
realtekALC5623 Codec Layout Guide ver 0.1” for proper component placement and routing are
very important. This document includes properly isolating the digital circuitry and analog
circuitry. The effects of Analogue/Digital ground and Power supply plane geometry include
decoupling/bypassing/filtering capacitors placement priorities, analog power supplies, and
analog ground planes. Those issues would be discussed as below.
very important. This document includes properly isolating the digital circuitry and analog
circuitry. The effects of Analogue/Digital ground and Power supply plane geometry include
decoupling/bypassing/filtering capacitors placement priorities, analog power supplies, and
analog ground planes. Those issues would be discussed as below.
5.1 The Layout Design of Ground and Supply Plane Geometry
Figure. 5-1 shows a top view layout of ground plane for ALC5623 codec. This layout
method is to separates the analog and digital ground planes with a 60 to 100 mils gap. The moat
helps to isolate noisy digital circuitry from quiet analog audio circuitry. The digital and analog
ground planes are tied together at one point (FB2, Ferrite Bead). This will be the “drawbridge”
that goes across the moat. Similarly, NO SIGNALS WHATEVER is permitted to cross the
moat (to do so creates a “slot antenna” radiator which will hammer your PCB layout with
crosstalk, and create huge amounts of EMI, totally defeating your purpose).
helps to isolate noisy digital circuitry from quiet analog audio circuitry. The digital and analog
ground planes are tied together at one point (FB2, Ferrite Bead). This will be the “drawbridge”
that goes across the moat. Similarly, NO SIGNALS WHATEVER is permitted to cross the
moat (to do so creates a “slot antenna” radiator which will hammer your PCB layout with
crosstalk, and create huge amounts of EMI, totally defeating your purpose).
Figure. 5-1 ALC5623 Ground plane