MAX4397 MAXIM [Maxim Integrated Products], MAX4397 Datasheet - Page 11

• Manufacturer Part Number: MAX4397
• Description: Audio/Video Switch For Dual SCART Connectors
• Manufacturer: MAXIM [Maxim Integrated Products]

The slow-switching feature allows for bidirectional, tri-
level, slow-switching input and output signals at pin
VCR_SS and TV_SS, respectively. The slow-switching
signals from the VCR set the aspect ratio or video source
of the TV screen. See the Slow Switching section.
Fast switching consists of two inputs from the encoder
and VCR, and one output to the TV to insert an on-
screen display (OSD). Fast switching is used to route
video signals from the VCR or from the encoder to the
TV. In addition, the fast-switching output can be config-
ured to a high or low voltage. Fast switching is con-
trolled through the I
Figure 1. MAX4397 Video Section Functional Diagram
Audio/Video Switch for Dual SCART Connectors
VCR_Y/CVBS_IN
ENC_Y/CVBS_IN
TV_Y/CVBS_IN
VCR_R/C_IN
ENC_R/C_IN
TV_R/C_IN
VCR_G_IN
ENC_G_IN
ENC_C_IN
VCR_B_IN
VCRIN_FS
ENC_B_IN
ENC_Y_IN
ENCIN_FS
______________________________________________________________________________________
2
C interface.
CLAMP/BIAS
CLAMP/BIAS
CLAMP/BIAS
CLAMP
CLAMP
CLAMP
CLAMP
CLAMP
CLAMP
CLAMP
CLAMP
BIAS
0.7V
0.7V
MAX4397
BIAS
FILTER
5V
0V
2kΩ
2kΩ
The digital block contains the 2-wire interface circuitry,
control, and status registers. The MAX4397 can be
configured through an I
DEV_ADDR sets the I
The MAX4397 switches video signals between an MPEG
decoder, TV SCART, and VCR SCART. The video switch
includes reconstruction filters, multiplexed video ampli-
fiers, and a Y-C mixer driver for an RF modulator. See
Figure 1 for the functional diagram of the video section.
While the SCART connector supports RGB, S-video, and
Composite video formats, RGB, and S-video typically
share a bidirectional set of SCART connector pins.
MIXER
FILTER
FILTER
FILTER
FILTER
FILTER
2
C-compatible address.
SCART Video Switching
PULLDOWN
PULLDOWN
VCRRCOUT
2
TVRCOUT
5dB, 6dB, OR 7dB
5dB, 6dB, OR 7dB
5dB, 6dB, OR 7dB
C-compatible interface.
VGA
VGA
VGA
x1
x2
x2
x2
x2
N
N
VCR_Y/CVBS_OUT
VCR_R/C_OUT
TV_R/C_OUT
TV_G_OUT
TV_B_OUT
TV_Y/CVBS_OUT
TVOUT_FS
RF_CVBS_OUT
11