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CXA2149Q

AOUT3 Mute Switch Data3 Bit 6

Mutes the LOUT3 and ROUT3 channels at the electronic volume control output so that a click free audio

channel change can take place.

AOUT3 mute bit

Meaning

0

Mute off

1

Mute on

The normal sequence for a click free channel change is as follows:-

1. Mute the channel 3 outputs (AOUT3 mute=1) with zero cross detection on (ZCD switch=1).

2. Change the channel 3 audio source, AOUT3L/R control.

3. Un-mute the channel 3 outputs still with zero cross detection on.

LO0 or LO1 Control Data2 Bit 7 (LO0 control) and Bit 6 (LO1 control)

Used to control the switching of the open collector outputs. The output transistor emitters are connected to

digital ground. Each output is capable of sinking 1 mA.

LO0 or LO1 bit

Collector output

0

Low impedance

1

High impedance

Zero Cross Detection Switch Data3 Bit 7

Switches the ZCD function on or off. When the ZCD is on, a volume control change or mute instruction sent

ZCD bit

Meaning

0

ZCD off

1

ZCD on

SYNC ID Switches Data6 Bit 5 (SYNC1 Switch) and Bit 4 (SYNC2 Switch)

Switches the respective SYNC ID circuit to an input our output. SYNC1 switches between the TV input and

YOUT1 output. SYNC2 switches between the CVIN1 input and YOUT2 output.

SYNC1 or SYNC2 bit

Input to SYNC ID

0

YOUT1 and YOUT2

1

YV and CVIN1

External Logic Inputs and Output

Hardware Mute

The hardware mute (Pin 17) provided will mute all audio outputs when the pin voltage exceeds 2.5 V.

In this case the muting will be instantaneous.

SCART Modes

Three Mode inputs (Pins 18, 19 and 20) are used to allow the format identification of up to three SCART ports.

See the description for mode status.

LO0 and LO1 Logic Outputs

application may require. See the description for LO0 and LO1 control.