ISL59960 Datasheet, PDF (9/17 Pages) Intersil Corporation – 960MegaQ™: An Automatic 960H and Composite Video Equalizer, Fully-Adaptive to 4000 Feet

ISL59960
Functional Description
960MegaQ™ Overview
960MegaQ™ is a fully automated, stand-alone equalizer for both
960H (WD1) and 720H (D1) composite video resolutions
transmitted over UTP (Unshielded Twisted Pair, i.e., Cat 5, Cat 6,
etc.) or coaxial (RG-59) cables.
Differential video signals sent over long distances of twisted pair
wire exhibit large high frequency attenuation, resulting in loss of
high frequency detail/blurring. The exact loss characteristic is a
complex function of wire gauge, length, composition, and
coupling to adjacent conductors.
The video signal can be restored by applying a filter with the
exact inverse transfer function to the far end signal. 960MegaQ™
is designed to compensate for the losses due to long cables, and
incorporates the functionality and flexibility to match a wide
variety of cable types and loss characteristics.
While 960MegaQ™ was designed and optimized for stand-alone
operation, with no need for any external control of any kind, it has
an optional SPI serial interface with some additional features.
See “Additional Equalization Modes Available With the Serial
Interface” on page 11 for more information on the features and
operation of the serial interface.
Equalization for Various Cable Types
TABLE 1. CABLE TYPES AND LENGTHS
CABLE TYPE
MAXIMUM
LENGTH SUPPORTED
Copper-Core
Cat 5/Cat 5e
4000 feet
Cat 6
4000 feet
Coaxial - RG-59
5000 feet
Non-Copper-Core (Note)
Cat 5/Cat 5e CCA
(Copper-Coated Aluminum Core)
2000 feet
Coaxial - RG-59 CCS
(Copper-Coated Steel Core)
1500 feet
NOTE: Image quality will be significantly improved over unequalized
cable, but there will still be some image smearing due to the high
resistance of the core material.
Ferrite Bead –
DC resistance = 1Ω,
600Ω at 100MHz,
100mA DC current rating +5V
C7
0.1µF
C8 C9
0.1µF 4.7µF
DIFFERENTIAL
VIDEO INPUT+
5V _Z1
TVS
DIFFERENTIAL
VIDEO INPUT-
5V _Z2
TVS
C1
1.0µF
R3 ^{R1 49.9Ω}
1kΩ _{R2 49.9Ω}
1.0µF
C2
V_DD1
IN+
GND
IN-
VDD2
OUT
CFB
ISL59960 _VREF
TVS = Transient Voltage Suppressor
a.k.a. Transorb
SERIAL
INTERFACE
(OPTIONAL)
SEN
SCK
SD
EQ_DISABLE
COLOR
INVERT
LOCKED
GND
FREEZE
R6 75.0Ω _VIDEO
C5
300Ω _0.047µF
OUT
C4 ^R5
1500pF
Internally
Generated
C6
0.47µF
Freezes EQ once
lock is achieved.
Tie FREEZE low if
not used.
FIGURE 9. APPLICATION CIRCUIT FOR UTP CABLE
9
FN8358.0
December 18, 2012