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Rainbow Electronics MAX9656 User Manual

General description, Applications, Features

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General Description

The MAX9655/MAX9656 dual SCART switches route
video signals between a set-top box decoder chip and
two external SCART connectors. Under the control of the
TV_SEL logic input, the MAX9655 selects whether the
CVBS and RGB signals from the encoder or the VCR
SCART are routed to the TV SCART. The CVBS signal
from the encoder is always routed to the VCR SCART.

The MAX9656 is similar to the MAX9655 except that
under the control of the VCR_SEL logic input, the
MAX9656 selects whether the CVBS signal from the
encoder or the TV SCART is routed to the VCR SCART.
The MAX9656 also features a low-power shutdown
mode, in which quiescent current falls to 35µA.

The incoming video signals must be AC-coupled to the
inputs, which have sync-tip clamps to set the internal
DC level. After the input stages, multiplexers select
which video signals are routed to the reconstruction fil-
ters and output amplifiers. The reconstruction filters are
optimized for standard-definition signals and typically
have ±1dB passband flatness out to 9.5MHz and 47dB
attenuation at 27MHz.

The amplifiers have 2V/V gain, and the outputs can be
DC-coupled to a 75

Ω load, which is the equivalent of

two video loads, or AC-coupled to a 150

Ω load.

Applications

SCART Set-Top Boxes

Features

Dual SCART Support for Video Signals
Supports CVBS Input from TV SCART (MAX9656)
Reconstruction Filters with 9.5MHz Passband and

47dB Attenuation at 27MHz

Fixed Gain of 2V/V
Input Sync-Tip Clamps
2.7V to 3.6V Single-Supply Operation

MAX9655/MAX9656

Low-Power Video Switches

for Dual SCART Connectors

________________________________________________________________

Maxim Integrated Products

1

19-4238; Rev 0; 8/08

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

UNKNOWN

BIAS

ENC_CVBS_IN

300mV

ENC_R_IN

TV_G_OUT

ENC_G_IN

ENC_B_IN

TV_B_OUT

TV_CVBS_OUT

TV_R_OUT

VCR_CVBS_OUT

VCR_CVBS_IN

VCR_R_IN

VCR_G_IN

VCR_B_IN

TV_SEL

TV_SEL

0

1

0

1

0

1

0

1

0

V

DD

GND

MAX9655

LPF

BUFFER

CLAMPREF

LPF

BUFFER

CLAMPREF

LPF

BUFFER

CLAMPREF

LPF

BUFFER

CLAMPREF

2V/V

2V/V

2V/V

2V/V

2V/V

LPF

BUFFER

CLAMPREF

Functional Diagram

Ordering Information

PART

PIN-PACKAGE

TV SCART CVBS

RETURN SUPPORT

MAX9655AEE+

16 QSOP

No

MAX9656AEP+*

20 QSOP

Yes

Note: All devices are specified over the -40°C to +125°C oper-
ating temperature range.

+

Denotes a lead-free/RoHS-compliant package.

*

Future product—contact factory for availability.

Pin Configurations and Typical Application Circuits appear
at end of data sheet.