1
®
FN7173.3
EL4583
Sync Separator, 50% Slice, S-H, Filter,
HOUT
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 2.0VP-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.
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
Ordering Information
PART NUMBER
PART
MARKING
TAPE &
REEL PACKAGE
PKG.
DWG. #
EL4583CN EL4583CN - 16 Ld PDIP MDP0031
EL4583CS EL4583CS - 16 Ld SO (0.150”) MDP0027
EL4583CS-T7 EL4583CS 7” 16 Ld SO (0.150”) MDP0027
EL4583CS-T13 EL4583CS 13” 16 Ld SO (0.150”) MDP0027
EL4583CSZ
(Note)
EL4583CSZ - 16 Ld SO (0.150”)
(Pb-free)
MDP0027
EL4583CSZ-T7
(Note)
EL4583CSZ 7” 16 Ld SO (0.150”)
(Pb-free)
MDP0027
EL4583CSZ-T13
(Note)
EL4583CSZ 13” 16 Ld SO (0.150”)
(Pb-free)
MDP0027
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.
1
2
3
4
16
15
14
13
5
6
7
12
11
10
8 9
FILTER CUT OFF
SET DETECT LEVEL
COMPOSITE SYNC OUT
FILTER INPUT
VERTICAL SYNC OUT
DIGITAL GND
FILTER OUTPUT
COMPOSITE VIDEO INPUT
ANALOG GND
HORIZONTAL SYNC OUT
VDD
ODD/EVEN OUTPUT
RSET*
BURST/BACK PORCH OUTPUT
NO SIGNAL DETECT OUTPUT
LEVEL OUTPUT
EL4583
(16 LD SO, PDIP)
TOP VIEW
*NOTE: RSET must be a 1% register
Data Sheet November 12, 2010
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 trademark owned by Intersil Corporation or one of its subsidiaries.
Copyright Intersil Americas Inc. 2002, 2003, 2005, 2006, 2010. All Rights Reserved
All other trademarks mentioned are the property of their respective owners. Manufactured under U.S. Patent 5,528,303.
2FN7173.3
November 12, 2010
Absolute Maximum Ratings (TA = 25°C)
VCC Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7V
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Pin Voltages . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to VCC +0.5V
Operating Temperature Range . . . . . . . . . . . . . . . . .-40°C to +85°C
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Curves
Die Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
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 = TA
DC Electrical Specifications VDD = 5V, TA = 25°C, RSET = 681kΩ, RF = 22kΩ, RLV = 82kΩ
PARAMETER DESCRIPTION MIN TYP MAX UNIT
IDD VDD = 5V (Note 1) 2.5 4 mA
Clamp Voltage Pins 4, 8, unloaded 1.3 1.55 1.8 V
Discharge Current Pins 4, 8, with signal (VIN = 2V) 3 6 12 µA
Discharge Current Pins 4, 8, no signal (Note 2) 10 µA
Clamp Charge Current Pins 4, 8, VIN = 1V 234mA
Ref. Voltage VREF Pin 12, VDD = 5V (Note 3) 1.5 1.75 2 V
Filter Reference Voltage, VRF Pin 1 0.35 0.5 0.65 V
Level Reference Current Pin 2 (Note 4) 1.5 2.5 3.5 µA
VOL Output Low Voltage IOL = 1.6mA 350 800 mV
VOH Output High Voltage IOH = -40µA 4 V
IOH = -1.6mA 2.4 4 V
NOTES:
1. No video signal, outputs unloaded.
2. At loss of signal (pin 10 high) the pull down current source switches to a value of 10µA.
3. Tested for VDD 5V ±5%.
4. Current sourced from pin 2 is VREF/RSET.
Dynamic Specifications RF = 22kΩ, RSET = 681kΩ, VDD = 5V, Video Input = 1VP-P
, TA = 25°C, CL = 15pF, IOH = -1.6mA, IOL =1.6mA
PARAMETER DESCRIPTION MIN TYP MAX UNIT
Horizontal Pulse Width, Pin 15, tH(Note 1) 3.8 5 6.2 µs
Vertical Sync Width, Pin 5, tVS (Note 2) 195 µs
Burst/Back Porch Width, Pin 11, tB(Note 1) 2.7 3.7 4.7 µs
Filter Attenuation FIN = 3.6MHz (Note 3) 12 dB
Comp. Sync Prop. Delay, tCS VIN (Pin 4) - comp sync 250 400 ns
Input Dynamic Range p-p NTSC signal 0.4 2 V
Slice Level Input voltage = 1VP-P 40 50 60 %
VSLICE/VBLANK 40 50 60
Level Out, Pin 9 Input voltage = 1VP-P, pin 4 500 600 700 mV
Vertical Sync Default Time, tVSD (Note 4) 27 36 57 µs
Loss of Signal Time-Out Pin 10 400 600 800 µs
Burst/Back Porch Delay, tBD (See Figure 4) 250 400 ns
NOTES:
1. Width is a function of RSET.
2. C/S, vertical, back porch and H are all active low, VOH = 0.8V; vertical is 3H lines wide of NTSC signal.
3. Attenuation is a function of RF
. See filter typical characteristics.
4. Vertical pulse width in absence of serrations on input signal.
EL4583
3FN7173.3
November 12, 2010
Pin Descriptions
PIN
NUMBER PIN NAME PIN FUNCTION
1 Filter Cut-Off A resistor RF connected between this input and ground determines the input filter characteristic. Increasing RF
increases the filter 3.58MHz color burst attenuation. See the typical performance characteristics.
2 Set Detect
Level
A resistor RLV connected between pin 2 and ground determines the value of the minimum signal which triggers the
loss of signal output on pin 10. The relationship is VPMIN = 0.75RLV/RSET
, where VPMIN is the minimum detected
sync pulse amplitude applied to pin 4. See the typical performance characteristics.
3 Composite
Sync Output
This output replicates all the sync inputs on the input video.
4 Filter Input The 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.
5 Vertical 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
Ground
This is the ground return for digital buffer outputs.
7 Filter 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.
8 Video Input This 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.
9 Level 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.
10 No Signal
Detect
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 RLV on pin 2. There will be several horizontal lines delay before the output is
initiated.
11 Burst/Back
Porch Output
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 RSET
. This output can be used for d.c. restore functions where the back porch level is a known reference.
12 RSET The current through the resistor RSET determines the timing of the functions within the I.C. These functions include
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 RSET is 681k 1%. RSET must be a 1% resistor.
13 Odd/Even
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.
14 VDD 5V The 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.
15 Horizontal
Sync Output
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.
16 Analog
Ground
This is the ground return for the signal paths in the chips, RSET
, RF and RLV.
EL4583
4FN7173.3
November 12, 2010
Typical Performance Curves
RSET vs
Horizontal Frequency
Back Porch Clamp
On Time vs RSET
Vertical Default Delay
Time vs RSET
Filter 3dB BW vs RFLevel Out (Pin 9) vs
Sync. Tip Amplitude
Minimum Signal Detect
vs RLV
Filter Attenuation vs RF @
f = 3.58MHz
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.
EL4583
5FN7173.3
November 12, 2010
Typical Performance Curves (Continued)
Package Power Dissipation vs Ambient
Temperature
JEDEC JESD51-3 Low Effective Thermal
Conductivity Test Board
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
0255075100125150
Ambient Temperature (°C)
Power Dissipation (W)
85
1.54W
PDIP16
θ
JA
=81°C/W
1.136W
SO16 (0.150”)
θ
JA
=110°C/W
2
1.8
1.6
1.4
1.2
1
0.8
0.4
0.2
0
Power Dissipation (W)
0.6
0255075100125150
Ambient Temperature (°C)
Package Power Dissipation vs Ambient
Temperature
JEDEC JESD51-7 High Effective Thermal
Conductivity Test Board
1.786W
1.563W
SO16 (0.150”)
θJA=80°C/W
PDIP16
θJA=70°C/W
EL4583
6FN7173.3
November 12, 2010
Timing Diagram
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.
EL4583
7FN7173.3
November 12, 2010
FIGURE 2.
FIGURE 3.
EL4583
8FN7173.3
November 12, 2010
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 C1,
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 VR1. Thus the sync tip, the most negative
part of the video waveform, will be clamped at 1.5V. The
current source I1, nominally 6µA, charges the coupling
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
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 CI will
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 VDD less 1.5V, for black
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 I1 directly tracks
reference current ITR and thus increases with scan rate
adjustment, as explained later.
FIGURE 4. STANDARD (NTSC INPUT) H. SYNC DETAIL
EL4583
9
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 implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
FN7173.3
November 12, 2010
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 VREF) with high immunity
to supply voltage variation are derived on the chip.
Reference VR4 with op-amp A2 forces pin 12 to a reference
voltage of 1.7V nominal. Consequently, it can be seen that
the external resistance RSET will determine the value of the
reference current ITR. The internal resistance R3 is only
about 6kΩ, much less than RSET
. All the internal timing
functions on the chip are referenced to ITR and have
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 VR2 which is referenced at a
fixed level above the clamp voltage VR1. The output of C2
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 RSET through IOT
.
The 50% level of the sync tip is derived through the resistor
divider R1 and R2, from the sample and held voltages VTIP
and VBP and applied to the plus input of comparator C1.
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 IOT and
VR3, the time-out period being inversely proportional to the
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 circuit. The 2H
eliminator initiates a time out period after a horizontal pulse
is generated. The time out period is a function of IOT which
is set by RSET
.
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 IOT and will therefore track the scan rate
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 RLV
on pin 2. Pin 10 output goes high when the VTIP falls below
RLV set value.
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.
EL4583
10 FN7173.3
November 12, 2010
Block Diagram
FIGURE 5. STANDARD (NTSC INPUT) H. SYNC DETAIL
* NOTE: RSET must be a 1% resistor.
EL4583
