User Manual

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USERS MANUAL
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3.4 Analog Audio Group Recommended Circuitry
3.4.1 Creating an analog ground
An analog ground plane should be generated, which connects to GND in one point so
that high frequency digital current is not floating through the analog ground. Connecting
the analog ground in only one point avoids ground currents from power supplies and
other high current circuitry from creating noise in the analog circuitry. This common
point should be located where the analog supply voltage (VANA) is generated (at filter
(A), or regulator (B) depending on implementation).
3.4.2 Creating an analog reference voltage (BIAS)
The BIAS reference should be generated from the analog supply voltage (VANA) and
be referenced to the analog ground. This reference shall be used to bias all analog
circuitry in the application.
5V
VANA
12V
VANA
Regulator
BA
-
+
0
100k
100k
VANA
BIAS