cxa2149q Sony Electronics, cxa2149q Datasheet - Page 21

• Manufacturer Part Number: cxa2149q
• Description: I2c-bus-compatible Audio/video Switch
• Manufacturer: Sony Electronics

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
0
1
The normal sequence for a click free channel change is as follows:-
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
0
1
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
via the I
ZCD bit
0
1
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
0
1
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
LO0 and LO1 are open collector output I
application may require. See the description for LO0 and LO1 control.
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.
2
C bus will only be implemented when a minimal, ie., zero cross, signal amplitude is detected.
Meaning
Mute off
Mute on
Collector output
Low impedance
High impedance
Meaning
ZCD off
ZCD on
Input to SYNC ID
YOUT1 and YOUT2
YV and CVIN1
2
C controllable logic switch for any external switching functions an
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CXA2149Q