PGA4311 Datasheet, PDF (11/15 Pages) Burr-Brown (TI) – 4 CHANNEL AUDIO VOLUME CONTROL

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MUTE FUNCTION
Muting can be achieved by either hardware or software
control. Hardware muting is accomplished via the
MUTE input, and software muting by loading all zeroes
into the volume control register.
MUTE disconnects the internal buffer amplifiers from
the output pins and terminates the outputs with 10kΩ
resistors to ground. The mute is activated with a zero
crossing detection (independent of the zero cross en-
able status) or an 16ms time-out to eliminate any audi-
ble “clicks” or “pops”. MUTE also initiates an internal
offset calibration.
A software mute is implemented by loading all zeroes
into the volume control register. The internal amplifier
is set to unity gain with the amplifier input connected to
AGND.
PGA4311
SBOS230A – MARCH 2002 – REVISED JUNE 2002
APPLICATIONS INFORMATION
This section includes additional information that is per-
tinent to designing the PGA4311 into an end applica-
tion.
RECOMMENDED CONNECTION DIAGRAM
Figure 5 depicts the recommended connections for the
PGA4311. Power-supply bypass capacitors should be
placed as close to the PGA4311 package as physically
possible.
PRINTED CIRCUIT BOARD (PCB) LAYOUT GUIDE-
LINES
It is recommended that the ground planes for the digital
and analog sections of the PCB be separate from one
another. The planes should be connected at a single
point. See Figure 6 for the recommended PCB floor
plan for the PGA4311.
Figure 5. Recommended Connection Diagram.
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