CXA2126 Sony Corporation, CXA2126 Datasheet - Page 21

• Manufacturer Part Number: CXA2126
• Description: Audio/Video Switch with Electronic Volume for 2 Scart
• Manufacturer: Sony Corporation

CXA2126Q
Description of Operation
1. Explanation of Video Section
The video section comprises of 11 high impedance inputs switched through to 6 video outputs. A +6dB internal
amplifier is connected to each output. The amplifier is required to compensate for the 6dB attenuation which
occurs at the external emitter follower stage used for driving video loads. All video outputs have an integrated
100Ω series protection resistor. The typical external configuration is shown in Fig. 1-1.
VID_V
= 9V
CC
Scart In
+12V
Switch
Scart Out
75
0.47 F
100
BC547B
Amp
75
Load
75
120k
75
1k
Vbias
Vbias
Video Element
Fig. 1-1. Video Circuit Element: 6dB gain amplifier with external emitter follower
Switching the Video Outputs Off
2
Each video output can be individually turned off using the I
C. When turned off, the output is high impedance
and hence the current consumption of the external emitter followers is reduced.
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