The EL4583 extracts timing from video sync in NTSC, PAL,
and SECAM systems, and non standard formats, or from
computer graphics operating at higher scan rates. Timing
adjustment is via an external resistor. Input without valid
vertical interval (no serration pulses) produces a default
vertical output.
Outputs are: composite sync, vertical sync, filter, burst/back
porch, horizontal, no signal detect, level, and odd/even
output (in interlaced scan formats only).
The EL4583 sync slice level is set to the mid-point between
sync tip and the blanking level. This 50% point is determined
by two internal sample and hold circuits that track sync tip
and back porch levels. It provides hum and noise rejection
and compensates for input levels of 0.5V to 2.0V
P-P
.
A built in filter attenuates the chroma signal to prevent color
burst from disturbing the 50% sync slice. Cut off frequency is
set by a resistor to ground from the Filter Cut Off pin.
Additionally, the filter can be by-passed and video signal fed
directly to the Video Input.
The level output pin provides a signal with twice the sync
amplitude which may be used to control an external AGC
function. A TTL/CMOS compatible No Signal Detect Output
flags a loss or reduction in input signal level. A resistor sets
the Set Detect Level.
The EL4583 is manufactured using Intersil’s high
performance analog CMOS process.
Ordering Information
PART
PART NUMBER
EL4583CNEL4583CN-16 Ld PDIPMDP0031
EL4583CSEL4583CS-16 Ld SO (0.150”) MDP0027
EL4583CS-T7EL4583CS7”16 Ld SO (0.150”) MDP0027
EL4583CS-T13 EL4583CS13”16 Ld SO (0.150”) MDP0027
EL4583CSZ
(Note)
EL4583CSZ-T7
(Note)
EL4583CSZ-T13
(Note)
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are RoHS compliant and
compatible with both SnPb and Pb-free soldering operations. Intersil
Pb-free products are MSL classified at Pb-free peak reflow
temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.
MARKING
EL4583CSZ-16 Ld SO (0.150”)
EL4583CSZ7”16 Ld SO (0.150”)
EL4583CSZ13”16 Ld SO (0.150”)
TAPE &
REELPACKAGE
(Pb-free)
(Pb-free)
(Pb-free)
PKG.
DWG. #
MDP0027
MDP0027
MDP0027
FN7173.2
Features
• NTSC, PAL, and SECAM sync separation
• Single supply, +5V operation
• Precision 50% slicing
• Built-in programmable color burst filter
• Decodes non-standard vertical
• Horizontal sync output
• Sync. pulse amplitude output
• Same socket can be used for 8 Ld EL4581
• Low-power CMOS
• Detects loss of signal
• Resistor programmable scan rate
• Few external components
• Available in 16 Ld PDIP and 16 Ld SO (0.150”) packages
• Pb-free plus anneal available (RoHS compliant)
Applications
• Video special effects
• Video test equipment
• Video distribution
•Multimedia
• Displays
•Imaging
• Video data capture
• Video triggers
Pinout
EL4583
(16 LD SO, PDIP)
TOP VIEW
FILTER CUT OFF
SET DETECT LEVEL
COMPOSITE SYNC OUT
FILTER INPUT
VERTICAL SYNC OUT
DIGITAL GND
FILTER OUTPUT
COMPOSITE VIDEO INPUT
*NOTE: R
1
2
3
4
5
6
7
89
must be a 1% register
SET
ANALOG GND
16
HORIZONTAL SYNC OUT
15
VDD
14
ODD/EVEN OUTPUT
13
RSET*
12
BURST/BACK PORCH OUTPUT
11
NO SIGNAL DETECT OUTPUT
10
LEVEL OUTPUT
1
All other trademarks mentioned are the property of their respective owners.
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
| Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2002, 2003, 2005, 2006. All Rights Reserved
Manufactured under License, U.S. Patents 5,486,869; 5,754,250.
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: TJ = TC = T
DC Electrical Specifications V
= 25°C)
A
= 5V, TA = 25°C, R
DD
CC
Operating Temperature Range . . . . . . . . . . . . . . . . .-40°C to +85°C
Level Out, Pin 9Input voltage = 1V
Vertical Sync Default Time, t
VSD
(Note 4)273657µs
P-P
pin 4500600700mV
P-P,
405060%
405060
Loss of Signal Time-OutPin 10400600800µs
Burst/Back Porch Delay, t
BD
(See Figure 4)250400ns
NOTES:
1. Width is a function of R
2. C/S, vertical, back porch and H are all active low, V
3. Attenuation is a function of R
.
SET
. See filter typical characteristics.
F
= 0.8V; vertical is 3H lines wide of NTSC signal.
OH
4. Vertical pulse width in absence of serrations on input signal.
2
FN7173.2
May 5, 2006
EL4583
Pin Descriptions
PIN
NUMBERPIN NAMEPIN FUNCTION
1Filter Cut-Off A resistor R
increases the filter 3.58MHz color burst attenuation. See the typical performance characteristics.
2Set Detect
Level
A resistor R
loss of signal output on pin 10. The relationship is V
sync pulse amplitude applied to pin 4. See the typical performance characteristics.
3Composite
This output replicates all the sync inputs on the input video.
Sync Output
4Filter InputThe filter is a 3 pole active filter with a gain of 2, designed to produce a constant phase delay of nominally 260ns with
signal amplitude. Resistor RF on pin 1 controls the filter cut-off. An internal clamp sets the minimum voltage on pin
4 at 1.55V when the input becomes low impedance. Above the clamp voltage, an input current of 1µA charges the
input coupling capacitor. With loss of signal, the current source switches to a value of 10µA, for faster signal recovery .
5Vertical Sync
Output
The vertical sync output is synchronous with the first serration pulse rising edge in the vertical interval of the input
signal and ends on the trailing edge of the first equalizing Output pulse after the vertical interval. It will therefore be
slightly more than 3H lines wide.
6Digital
This is the ground return for digital buffer outputs.
Ground
7Filter Output Output of the active 3 pole filter which has its input on pin 4. It is recommended to ac couple the output to pin 8.
8Video InputThis input can be directly driven by the signal if it is desired to bypass the filter, for example, in the case of strong
clean signals. This input is 6dB less sensitive than the filter input.
9Level Output This pin provides an analog voltage which is nominally equal to twice the sync pulse amplitude of the video input
signal applied to pin 4. It therefore provides an indication of signal strength.
10No Signal
Detect
Output
11Burst/Back
Porch Output
This is a digital output which goes high when either a) loss of input signal or b) the input signal level falls below a
predetermined amplitude as set by R
initiated.
The start of back porch output is triggered on the trailing edge of normal H sync, and on the rising edge of serration
pulses in the vertical interval. The pulse is timed out internally to produce a one-shot output. The pulse width is a
function of R
12R
SET
The current through the resistor R
the sampling of the sync pulse 50% point, back porch output and the 2H eliminator. For faster scan rates, the resistor
needs to be reduced inversely. For NTSC 15.7kHz scan rate R
13Odd/Even
Output
14V
DD
15Horizontal
Sync Output
Odd-even output is low for even field and high for odd field. The operation of this circuit has been improved for
rejecting spurious noise pulses such as those present in VCR signals.
5VThe internal circuits are designed to have a high immunity to supply variations, although as with most I.C.s a 0.1µF
decoupling capacitor is advisable.
This output produces only true H pulses of nominal width 5µs. The leading edge is triggered from the leading edge
of the input H sync, with the same prop. delay as the composite sync. The half line pulses present in the input signal
during vertical blanking are eliminated with an internal 2H eliminator circuit.
16Analog
This is the ground return for the signal paths in the chips, R
Ground
connected between this input and ground determines the input filter characteristic. Increasing RF
F
connected between pin 2 and ground determines the value of the minimum signal which triggers the
LV
on pin 2. There will be several horizontal lines delay before the output is
LV
. This output can be used for d.c. restore functions where the back porch level is a known reference.
SET
determines the timing of the functions within the I.C. These functions include
SET
MIN = 0.75RLV/R
P
SET
, RF and RLV.
SET
, where VPMIN is the minimum detected
SET
is 681k 1%. R
must be a 1% resistor.
SET
3
FN7173.2
May 5, 2006
Typical Performance Curves
R
vs
SET
Horizontal Frequency
EL4583
Back Porch Clamp
On Time vs R
SET
Vertical Default Delay
Time vs R
SET
Filter 3dB BW vs R
F
Filter Attenuation vs RF @
f = 3.58MHz
Level Out (Pin 9) vs
Sync. Tip Amplitude
Minimum Signal Detect
vs R
LV
Note 1: For RLV < 1000kΩ, no signal detect output (pin 10) will default high at
minimum signal sensitivity specification, or at complete loss of signal.
4
FN7173.2
May 5, 2006
Typical Performance Curves (Continued)
EL4583
Package Power Dissipation vs Ambient
Temperature
JEDEC JESD51-3 Low Effective Thermal
Conductivity Test Board
1.8
1.54W
1.6
1.4
1.136W
1.2
1
6
S
1
O
0.8
0.6
Power Dissipation (W)
0.4
0.2
=
θ
A
J
0
0255075100125150
P
1
D
6
P
I
θ
=
C
8
°
W
/
1
J
A
)
(
0
.
1
”
5
0
W
/
°
1
C
0
1
Ambient Temperature (°C)
85
Package Power Dissipation vs Ambient
Temperature
JEDEC JESD51-7 High Effective Thermal
Conductivity Test Board
2
1.8
1.786W
1.6
1.563W
1.4
1.2
1
SO16 (0.150”)
θJA=80°C/W
0.8
0.6
Power Dissipation (W)
0.4
0.2
0
0255075100125150
Ambient Temperature (°C)
PDIP16
θJA=70°C/W
5
FN7173.2
May 5, 2006
Timing Diagram
EL4583
NOTES:
b. The composite sync output reproduces all the video input sync pulses, with a propagation delay.
c. Vertical sync leading edge is coincident with the first vertical serration pulse leading edge, with a propagation delay.
d. Odd-even output is low for even field, and high for odd field.
e. Back porch goes low for a fixed pulse width on the trailing edge of video input sync pulses. Note that for serration pulses during
vertical, the back porch starts on the rising edge of the serration pulse (with propagation delay).
f. Horizontal sync output produces the true “H” pulses of nominal width of 5µs. It has the same delay as the composite sync.
FIGURE 1.
6
FN7173.2
May 5, 2006
EL4583
FIGURE 2.
FIGURE 3.
7
FN7173.2
May 5, 2006
EL4583
FIGURE 4. STANDARD (NTSC INPUT) H. SYNC DETAIL
Description of Operation
A simplified block schematic is shown in Figure 1. The
following description is intended to provide the user with
sufficient information to understand the effects of the
external components and signal conditions on the outputs of
the integrated circuit.
The video signal is AC coupled to pin 4 via the capacitor C
nominally 0.1µF. The clamp circuit A1 will prevent the input
signal on pin 4 going more negative than 1.5V, the value of
reference voltage V
. Thus the sync tip, the most negative
R1
part of the video waveform, will be clamped at 1.5V. The
current source I
, nominally 6µA, charges the coupling
1
capacitor during the remaining portion of the H line,
approximately 58µs for a 15.75kHz timebase. From I • t = C • V ,
the video time-constant can be calculated. It is important to
note that the charge taken from the capacitor during video
8
1
must be replaced during the sync tip time, which is much
shorter, (ratio of x 12.5). The corresponding current to
restore the charge during sync will therefore be an order of
magnitude higher, and any resistance in series with C
will
I
cause sync tip crushing. For this reason, the internal series
resistance has been minimized and external high resistance
values in series with the input coupling capacitor should be
,
avoided. The user can exercise some control over the value
of the input time constant by introducing an external pull-up
resistance from pin 4 to the 5V supply. The maximum
voltage across the resistance will be V
less 1.5V , for black
DD
level. For a net discharge current greater than zero, the
resistance should be greater than 450k. This will have the
effect of increasing the time constant and reducing the
degree of picture tilt. The current source I
reference current I
and thus increases with scan rate
TR
directly tracks
1
adjustment, as explained later.
FN7173.2
May 5, 2006
EL4583
The signal is processed through an active 3 pole filter (F1)
designed for minimum ripple with constant phase delay. The
filter attenuates the color burst by 12dB and eliminates fast
transient spikes without sync crushing. An external filter is
not necessary. The filter also amplifies the video signal by
6dB to improve the detection accuracy. The filter cut-off
frequency is controlled by an external resistor from pin 1 to
ground.
Internal reference voltages (block V
) with high immunity
REF
to supply voltage variation are derived on the chip.
Reference V
with op-amp A2 forces pin 12 to a reference
R4
voltage of 1.7V nominal. Consequently, it can be seen that
the external resistance R
reference current I
. The internal resistance R3 is only
TR
about 6kΩ, much less than R
functions on the chip are referenced to I
will determine the value of the
SET
. All the internal timing
SET
and have
TR
excellent supply voltage rejection.
To improve noise immunity, the output of the 3 pole filter is
brought out to pin 7. It is recommended to AC couple the
output to pin 8, the video input pin. In case of strong clean
video signal, the video input pin, pin 8, can be driven by the
signal directly.
Comparator C2 on the input to the sample and hold block
(S/H) compares the leading and trailing edges of the sync.
pulse with a threshold voltage V
fixed level above the clamp voltage V
which is referenced at a
R2
. The output of C2
R1
initiates the timing one-shots for gating the sample and hold
circuits. The sample of the sync tip is delayed by 0.8µs to
enable the actual sample of 2µs to be taken on the optimum
section of the sync. pulse tip. The acquisition time of the
circuit is about three horizontal lines. The double poly CMOS
technology enables long time constants to be achieved with
small high quality on-chip capacitors. The back porch
voltage is similarly derived from the trailing edge of sync,
which also serves to cut off the tip sample if the gate time
exceeds the tip period. Note that the sample and hold gating
times will track R
through IOT.
SET
The 50% level of the sync tip is derived through the resistor
divider R1 and R2, from the sample and held voltages V
and V
and applied to the plus input of comparator C1.
BP
TIP
This comparator has built in hysteresis to avoid false
triggering. The output of C2 is a digital 5V signal which feeds
the C/S output buffer B1, the vertical, back porch and
odd/even functions.
The vertical circuit senses C/S edges and initiates an
integrator which is reset by the shorter horizontal sync
pulses but times out with the longer vertical sync. pulse
widths. The internal timing circuits are referenced to I
V
, the time-out period being inversely proportional to the
R3
OT
and
timing current. The vertical output pulse is started on the first
serration pulse in the vertical interval and is then self-timed
out. In the absence of a serration pulse, an internal timer will
default the start of vertical.
The horizontal circuit senses C/S edges and produces the
true horizontal pulses of nominal width 5µs. The leading
edge is triggered from the leading edge of the input H sync,
with the same prop. delay as composite sync. The half line
pulses present in the input signal during vertical blanking are
removed with an internal 2H eliminator circui t . The 2H
eliminator initiates a time out period after a horizontal pulse
is generated. The time out period is a function of I
is set by R
SET
.
OT
which
The back porch is triggered from the sync tip trailing edge
and initiates a one-shot pulse. The period of this pulse is
again a function of I
and will therefore track the scan rate
OT
set by RESET.
The odd/even circuit (O/E) tracks the relationship of the
horizontal pulses to the leading edge of the vertical output
and will switch on every field at the start of vertical. Pin 13 is
high during an odd field.
Loss of video signal can be detected by monitoring the No
Signal Detect Output pin 10. The VTIP voltage held by the
sample and hold is compared with a voltage level set by R
LV
on pin 2. Pin 10 output goes high when the VTIP falls below
R
set value.
LV
VTIP voltage is also passed through an amplifier with gain of
2 and buffed to pin 9. This provides an indication of signal
strength. This signal (Level Output) can be used for AGC
applications.
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implicat ion or oth erwise u nde r any p a tent or p at ent r ights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
9
FN7173.2
May 5, 2006
Block Diagram
EL4583
10
* NOTE: R
FIGURE 5. STANDARD (NTSC INPUT) H. SYNC DETAIL
must be a 1% resistor.
SET
FN7173.2
May 5, 2006
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