APPLICATIONS INFORMATION
General guidance
The ZXFV4583 is a high speed mixed analog/digital
signal processing component requiring the
appropriatecare inthe layoutof theapplication printed
circuit board. A continuous ground plane construction
is preferred. Suitable power supply decoupling
suggested includes a 100nF leadless ceramic capacitor
close to the power supply connection at pin 14.
In order to avoid coupling between high speed logic
output signals and analog inputs, the test circuit layout
uses connections from the logic output pins routed
away from the analog pins. In the application, similar
care in the layout is required, keeping resistors, R
FILT
,
R
NOSIG
, and R
SET
close to their respective pins, in
particular routing signal CSYNC away from pins 1, 2
and 12.
Evaluation circuit
An evaluation circuit is available, designed to provide
demonstration of the ZXFV4583 function using 50 ⍀
test instruments. The schematic diagram is shown in
Figure 5 and the printed circuit layout is shown in
Figures 6, 7 and 8. The circuit includes the Zetex
ZXFV4089DC RestorationCircuit, which isdescribed in
the data sheet for that part. The ZXFV4089 uses the
Back Porch output from the ZXFV4583 in order to
control and stabilize the black level of a video
waveform.
BNC connector sockets allow connection of the
analog video and output to laboratory test
instruments via 50 ⍀ BNC cables. The circuit can be
adapted for 75 ⍀ use. The output circuit includes a
resistor matching circuit to present a load of 150 ⍀ to
the amplifier and simultaneously provide 50 ⍀ output
impedance. The attenuation of this matching circuit is
15.45 dB. As the amplifier is configured for a voltage
gain of 2, the overall gain in a 50 ⍀ system is:
6 - 15.45 = -9.45 dB.
Thesynchronizedlogicoutputsarebrought toaheader
for examination using oscilloscope probes. A set of
jumper links allow the selection of operation with or
without the built in color carrier filter. The selection is
depicted on the board itself.
Parts List
QTY CCTREF VALUE DESCRIPTION
Resistors, surface mount
1R151⍀ 0805
1 R2 22k⍀ 0805
1 R3 82k⍀ 0805
1 R4 681k⍀ 0805
2 R5, R12 2.2k⍀ 0805
3R6,R7,R81k⍀ 0805
1 R9 130⍀ 0805
1 R10 33⍀ 0805
1 R11 24⍀ 0805
Capacitors, surface mount
5
C1, C2,
C3, C5, C6
100nF ceramic X7R 50V 0805
1 C4 1nF ceramic NPO 50V 0805
1 C7 10nF ceramic X7R 50V 0805
2 C8, C9 10F
tantalum elec 16V
size C
Integrated circuits
1 U1 - ZXFV4583N16 - Zetex
1 U2 - ZXFV4089N8 - Zetex
Miscellaneous
2 J1, J2 -
Socket BNC PCB
straight flange e.g.
Tyco B35N14H999X99
1J3 -
Terminal block 3-way
IMO 20.501/3SB
1 PL1 -
Header 8 way single
row 2.54mm, Harwin
M20-9990805
1 PL2 -
Header 8 way double
row 2.54mm, Harwin M
3
TP1, TP2,
TP3
-
Test terminal, W.
Hughes 200-207
2 LK1, LK2 -
Jumper Link, Harwin
M7567-05
ZXFV4583
SEMICONDUCTORS
ISSUE 3 - NOVEMBER 2003
10
