Intersil EL4543IU Triple differential twisted-pair driver with common-mode sync encoding Datasheet

EL4543
®
Data Sheet
October 26, 2005
Triple Differential Twisted-Pair Driver with
Common-Mode Sync Encoding
The EL4543 is a high bandwidth triple differential amplifier
with integrated encoding of video sync signals. The inputs
are suitable for handling high speed video or other
communications signals in either single-ended or differential
form, and the common-mode input range extends all the way
to the negative rail enabling ground-referenced signalling in
single supply applications. The high bandwidth enables
differential signalling onto standard twisted-pair or coax with
very low harmonic distortion, while internal feedback
ensures balanced gain and phase at the outputs reducing
radiated EMI and harmonics.
Embedded logic encodes standard video horizontal and
vertical sync signals onto the common mode of the twisted
pair(s), transmitting this additional information without the
requirement for additional buffers or transmission lines. The
EL4543 enables significant system cost savings when
compared with discrete line driver alternatives.
The EL4543 is available in a 24 Ld QSOP package and is
specified for operation over the -40°C to +85°C temperature
range.
TABLE 1. SYNC SIGNAL ENCODING
H
V
COMMON
MODE A
(RED)
COMMON
MODE B
(GREEN)
COMMON
MODE C
(BLUE)
Low
High
3.0
2.0
2.5
Low
Low
2.5
3.0
2.0
High
Low
2.0
3.0
2.5
High
High
2.5
2.0
3.0
TABLE 2. INPUT LOGIC THRESHOLD (+5V SUPPLY)
VLO, max
0.8V
VHI, min
2V
FN7325.5
Features
• Fully differential inputs, outputs, and feedback
• 350MHz -3dB bandwidth
• 1200V/µs slew rate
• -75dB distortion at 5MHz
• Single 5V to 12V operation
• 50mA minimum output current
• Low power - 36mA total typical supply current
• Pb-free plus anneal available (RoHS compliant)
Applications
• Twisted-pair drivers
• Differential line drivers
• VGA over twisted-pair
• Transmission of analog signals in a noisy environment
Ordering Information
PART
NUMBER
PART
TAPE &
MARKING REEL
PACKAGE
PKG.
DWG. #
EL4543IU
EL4543IU
-
24 Ld QSOP
MDP0040
EL4543IU-T7
EL4543IU
7”
24 Ld QSOP
MDP0040
EL4543IU-T13
EL4543IU
13”
24 Ld QSOP
MDP0040
EL4543IUZ
(See Note)
EL4543IUZ
-
24 Ld QSOP
(Pb-Free)
MDP0040
EL4543IUZ-T7
(See Note)
EL4543IUZ
7”
24 Ld QSOP
(Pb-Free)
MDP0040
EL4543IUZ-T13 EL4543IUZ
(See Note)
13”
24 Ld QSOP
(Pb-Free)
MDP0040
EL4543IL
4543IL
-
20 Ld 4x4 QFN* MDP0046
EL4543IL-T7
EL4543IL-T13
4543IL
7”
20 Ld 4x4 QFN* MDP0046
4543IL
13”
20 Ld 4x4 QFN* MDP0046
EL4543ILZ
(See Note)
4543ILZ
-
20 Ld 4x4 QFN* MDP0046
(Pb-Free)
EL4543ILZ-T7
(See Note)
4543ILZ
7”
20 Ld 4x4 QFN* MDP0046
(Pb-Free)
EL4543ILZ-T13 4543ILZ
(See Note)
13”
20 Ld 4x4 QFN* MDP0046
(Pb-Free)
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.
*20 Ld 4x4 QFN, exposed pad 2.7 x 2.7mm
1
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. 2004, 2005. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
EL4543
Pinouts
20 VS-
HSYNC 6
19 NC
18 VOUTB+
NC 7
VINB+ 8
+
-
17 VOUTB16 NC
VINB- 9
15 VOUTC+
NC 10
VINC+ 11
+
-
16 VOUTA-
17 VOUTA+
HSYNC 2
14 VSTHERMAL
PAD
NC 3
13 NC
VINB+ 4
12 VOUTB+
VINB- 5
11 VOUTBVOUTC+ 10
VSYNC 5
VOUTC- 9
21 VS+
15 VS+
NC 8
NC 4
VSYNC 1
VINC- 7
22 NC
VINA- 3
18 EN
23 VOUTA-
VINC+ 6
VINA+ 2
+
-
20 VINA-
24 VOUTA+
EN 1
19 VINA+
EL4543
(20 LD QFN)
TOP VIEW
EL4543
(24 LD QSOP)
TOP VIEW
14 VOUTC13 NC
VINC- 12
2
FN7325.5
October 26, 2005
EL4543
Absolute Maximum Ratings (TA = 25°C)
Supply Voltage (VS+ & VS-). . . . . . . . . . . . . . . . . . . . . . . . . . . .+12V
Maximum Output Continuous Current . . . . . . . . . . . . . . . . . . ±70mA
Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C
Operating Junction Temperature . . . . . . . . . . . . . . . . . . . . . . +135°C
Ambient Operating Temperature . . . . . . . . . . . . . . . .-40°C to +85°C
VIN+, VINB . . . . . . . . . . . . . . . VS- + 0.8V (min) to VS+ - 0.8V (max)
VIN- - VINB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±5V
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. Typ values are for information purposes only. Unless otherwise noted, all tests are
at the specified temperature and are pulsed tests, therefore: TJ = TC = TA
Electrical Specifications
PARAMETER
VS+ = +5V, VS- = 0V, TA = 25°C, VIN = 0V, RL = 150Ω, unless otherwise specified.
DESCRIPTION
CONDITIONS
MIN
TYP
MAX
UNIT
AC PERFORMANCE
BW (-3dB)
-3dB Bandwidth
VOUT = 2VP-P
SR
Differential Slew Rate
RL = 200Ω
TSTL
350
MHz
1000
V/µs
Settling Time to 0.1%
13.6
ns
GBW
Gain Bandwidth Product
700
MHz
HD2
2nd Harmonic Distortion
f = 20MHz, RL = 200Ω
-70
dBc
HD3
3rd Harmonic Distortion
f = 20MHz, RL = 200Ω
-70
dBc
dP
Differential Phase @ 3.58MHz
0.01
°
dG
Differential Gain @ 3.58MHz
0.01
%
600
INPUT CHARACTERISTICS
VOS
Input Referred Offset Voltage
-10
2
10
mV
IIN
Input Bias Current (VIN+, VIN+)
-30
-15
-10
µA
ZIN
Differential Input Impedance
VDIFF
Differential Input Range
VCM
Input Common Mode Voltage Range
VN
Input Referred Voltage Noise
CMRR
Input Common Mode Rejection Ratio
EN
Threshold
180
kΩ
±0.75
V
0
VCM = 0 to 2V
2.3
V
27
nV/√Hz
80
dB
1.4
V
40
60
mA
1.82
1.96
60
OUTPUT CHARACTERISTICS
IOUT
Output Peak Current
DC PERFORMANCE
AV
Voltage Gain
VIN = 0.8VP-P
2.05
V/V
12
V
16.2
mA
SUPPLY CHARACTERISTICS
VSUPPLY
Supply Operating Range
IS
Power Supply Current (per Channel)
PSRR
Power Supply Rejection Ratio
3
VS+ to VS-
5
12.3
14.5
70
80
dB
FN7325.5
October 26, 2005
EL4543
Pin Descriptions
PIN NUMBER
PIN NAME
1
EN
PIN DESCRIPTION
EQUIVALENT CIRCUIT
Disables video inputs and outputs
EN
VSM
CIRCUIT 1
2
VINA+
Non-inventing input
3
VINA-
Inverting input
4, 7, 10, 13, 16, 19, 22
NC
Not connected
5
VSYNC
Vertical sync logic input
SYNC
VSM
CIRCUIT 2
6
HSYNC
Horizontal sync logic input
8
VINB+
Non-inverting input
9
VINB-
Inverting input
11
VINC+
Non-inverting input
12
VINC-
Inverting input
14
VOUTC-
Inverting output
15
VOUTC+
Non-inverting output
17
VOUTB-
Inverting output
18
VOUTB+
Non-inverting output
20
VS-
Negative supply
21
VS+
Positive supply
23
VOUTA-
Non-inverting output
24
VOUTA+
Inverting output
4
Reference Circuit 2
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
-42
GREEN CM
OUT (CH B
RED CM
OUT (CH C
VOLTAGE
(2.5V/DIV)
VSYNC
BALANCE ERROR (dB)
VOLTAGE
(0.5V/DIV)
BLUE CM
OUT (CH A
BALANCE ERROR=
20 LOG(∆VO,CM/∆VO,DIFF)
-46
-50
-54
-58
HSYNC
-62
100K
TIME (0.5ms/DIV)
1M
10M
100M
FREQUENCY (Hz)
FIGURE 1. COMMON MODE OUTPUT
4
CL=0pF
RL=500Ω
RL=200Ω
2
NORMALIZED GAIN (dB)
NORMALIZED GAIN (dB)
4
FIGURE 2. BALANCE ERROR
0
RL=100Ω
-2
RL=50Ω
-4
-6
100K
1M
100M
10M
RL=200Ω
8.2pF
0
2.2pF
-2
-4
-6
100K
1G
FIGURE 3. DIFFERENTIAL FREQUENCY RESPONSE FOR
VARIOUS RL - DIFF
0
12pF
8.2pF
2
4.7pF
0
2.2pF
-2
-4
-6
100K
1M
10M
100M
1G
FREQUENCY RESPONSE (Hz)
FIGURE 5. DIFFERENTIAL FREQUENCY RESPONSE FOR
VARIOUS CL - DIFF
5
10M
100M
1G
FIGURE 4. DIFFFERENTIAL FREQUENCY RESPONSE FOR
VARIOUS CL - DIFF
NORMALIZED GAIN (dB)
NORMALIZED GAIN (dB)
RL=100Ω
CL=2.2pF
1M
FREQUENCY RESPONSE (Hz)
FREQUENCY RESPONSE (Hz)
4
22pF
12pF
2
RL=200Ω
20
40
60
80
100
100K
1M
10M
100M
1G
FREQUENCY RESPONSE (Hz)
FIGURE 6. CMRR
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
(Continued)
4
THRESHOLD (V)
RELATIVE TO NEGATIVE SUPPLY
12
10
CMIR (V)
8
6
4
2
0
5
6
7
8
9
10
11
3.5
3
2.5
VSWITCH
2
1.5
1
0.5
0
12
5
6
7
SUPPLY VOLAGE (V)
8
9
10
11
12
SUPPLY VOLAGE (V)
FIGURE 7. COMMON MODE INPUT RANGE vs SUPPLY
VOLTAGE
FIGURE 8. HSYNC & VSYNC THRESHOLD vs SUPPLY VOLTAGE
0
0.04
0.035
0.03
CURRENT (A)
PSRR (dB)
-20
-40
-60
0.025
0.02
0.015
0.01
-80
0.005
-100
0
100K
10K
10M
1M
0
100M
RL=200Ω
5
6
FREQUENCY
7
8
9
10
11
12
SUPPLY VOLAGE (V)
FIGURE 10. ISUPPLY vs VSUPPLY
FIGURE 9. PSRR vs FREQUENCY
3
VOLTAGE (2V/DIV)
ENABLE DISABLE PIN (V)
3.5
2.5
2
1.5
1
2.5V
212ns
ENABLE
OUTPUT
SIGNAL
0.5
0
5
6
7
8
9
10
11
12
TIME (200ns/DIV)
SUPPLY VOLAGE (V)
FIGURE 11. ENABLE DISABLE vs SUPPLY VOLTAGE
6
FIGURE 12. ENABLE RESPONSE
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
(Continued)
RL=200Ω DIFF
CL=0pF
VOLTAGE (2V/DIV)
2.5V
VOLTAGE (120mV/DIV)
ENABLE
900ns
OUTPUT
SIGNAL
RISE
∆t=25ns
FALL
∆t=1.94ns
TIME (200ns/DIV)
TIME (20ns/DIV)
FIGURE 13. DISABLE RESPONSE
FIGURE 14. DIFFERENTIAL SMALL SIGNAL TRANSIENT
RESPONSE
9
RISE
∆t=2.81ns
COMMON MODE DC LEVEL (V)
VOLTAGE (235mV/DIV)
RL=200Ω DIFF
CL=0pF
FALL
∆t=2.31ns
LOGIC HSYNC=0V
8 VSYNC=0V
7
N
EE
GR
-B
CM
ED
-A R
CM
UE
C BL
C M-
6
5
4
3
2
1
0
TIME (20ns/DIV)
5
6
7
8
9
10
11
12
SUPPLY VOLAGE (V)
FIGURE 15. DIFFERENTIAL LARGE SIGNAL TRANSIENT
RESPONSE
FIGURE 16. COMMON MODE DC LEVEL vs SUPPLY
VOLTAGE
9
LOGIC HSYNC=0V
8 VSYNC=3V
7
COMMON MODE DC LEVEL (V)
COMMON MODE DC LEVEL (V)
9
D
RE
-A
CM
L UE
-C B
CM
EEN
B GR
C M-
6
5
4
3
2
1
0
5
6
7
8
9
10
11
12
SUPPLY VOLAGE (V)
FIGURE 17. COMMON MODE DC LEVEL vs SUPPLY VOLTAGE
7
LOGIC HSYNC=3V
8 VSYNC=0V
7
N
EE
GR
-B
M
C
L UE
-C B
CM
D
A RE
C M-
6
5
4
3
2
1
0
5
6
7
8
9
10
11
12
SUPPLY VOLAGE (V)
FIGURE 18. COMMON MODE DC LEVEL vs SUPPLY VOLTAGE
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
(Continued)
50
LOGIC HSYNC=3V
8 VSYNC=3V
7
C
6
M- C
OUTPUT IMPEDANCE (Ω)
COMMON MODE DC LEVEL (V)
9
UE
BL
ED
-A R
CM
N
REE
BG
C M-
5
4
3
2
AV=+2
40
30
20
10
1
0
5
6
7
8
9
10
11
0
10K
12
100K
FIGURE 19. COMMON MODE DC LEVEL vs SUPPLY VOLTAGE
100M
FIGURE 20. OUTPUT IMPEDANCE
10K
0
RL=200Ω DIFF
-20
1K
CROSSTALK (dB)
VOLTAGE NOISE (nV/√Hz),
CURRENT NOISE (pA/√Hz)
10M
FREQUENCY (Hz)
SUPPLY VOLAGE (V)
100
10
1
1M
-40
-60
-80
5
6
7
8
9
10
12
FREQUENCY (Hz)
-100
100K
1M
10M
100M
400M
FREQUENCY (Hz)
FIGURE 21. INPUT VOLTAGE AND CURRENT NOISE
FIGURE 22. CHANNEL ISOLATION vs FREQUENCY
NORMALIZED GAIN (dB)
5
3
1
VOP-P=200mV
-1
VOP-P=2V
-3
-5
100K
1M
10M
100M
1G
FREQUENCY (Hz)
FIGURE 23. FREQUENCY RESPONSE vs OUTPUT
AMPLITUDE
8
FIGURE 24. GAIN vs FREQUENCY - 2 CHANNELS
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
(Continued)
FIGURE 25. GAIN vs FREQUENCY - 2 CHANNELS
FIGURE 26. GAIN vs FREQUENCY - 2 CHANNELS
FIGURE 27. PHASE vs FREQUENCY - 2 CHANNELS
FIGURE 28. PHASE vs FREQUENCY - 2 CHANNELS
FIGURE 29. PHASE vs FREQUENCY - 2 CHANNELS
FIGURE 30. HARMONIC DISTORTION
9
FN7325.5
October 26, 2005
EL4543
Typical Performance Curves
(Continued)
FIGURE 31. HARMONIC DISTORTION
JEDEC JESD51-7 HIGH EFFECTIVE
THERMAL CONDUCTIVITY TEST BOARD
1.2
1.136W
1.2
1
θ
JA
=
0.8
0.6
POWER DISSIPATION (W)
POWER DISSIPATION (W)
1.4
FIGURE 32. HARMONIC DISTORTION
Q
SO
P
88 24
°C
/W
0.4
0.2
0
0
25
50
75 85 100
125
JEDEC JESD51-3 LOW EFFECTIVE
THERMAL CONDUCTIVITY TEST BOARD
1 870mW
0.8
θ
JA
=
0.6
0
24
W
0
25
50
75 85 100
125
150
FIGURE 34. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
0.8
JEDEC JESD51-3 AND SEMI G42-88 (SINGLE
LAYER) TEST BOARD
0.7 667mW
2.500W
POWER DISSIPATION (W)
POWER DISSIPATION (W)
C/
AMBIENT TEMPERATURE (°C)
JEDEC JESD51-7 HIGH EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD - QFN EXPOSED
DIEPAD SOLDERED TO PCB PER JESD51-5
(4
m QF
m N
θ
2
JA
=4 x 4 0
0 ° mm
C
/W )
2
1.5
1
0.5
0
OP
5°
0.2
150
FIGURE 33. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
2.5
11
0.4
AMBIENT TEMPERATURE (°C)
3
QS
0.6
(4 Q
m
F
JA m x N2
0
=
θ
0.5
15 4m
0°
C m)
/W
0.4
0.3
0.2
0.1
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
FIGURE 35. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
10
0
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
FIGURE 36. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
FN7325.5
October 26, 2005
EL4543
Operational Description and Application
Information
Introduction
The EL4543 is designed to differentially drive composite
RGB video signals onto twisted pair lines, while
simultaneously encoding horizontal and vertical sync signals
as common mode output. The entire video signal plus sync
can therefore be transmitted on 3 twisted pairs of wire. When
utilizing CAT-5 cable, the 4th available twisted pair can be
used for transmission of audio, data or control information.
The distribution of composite video over standard CAT-5
cable enables enormous cost and labor savings compared
with traditional coaxial cable, when considering both the
relative low price and ease of pulling CAT-5 cable.
Functional Description
ENABLE/DISABLE
The EL4543 provides three fully differential high-speed
amplifiers, suitable for driving high-resolution composite
video signals onto twisted pair or standard coaxial cable.
The input common-mode range extends to the negative rail,
allowing simple ground-referenced input termination to be
used with a single supply. The amplifiers provide a fixed gain
of +2 to compensate for standard video cable termination
schemes. Horizontal and Vertical sync signals (HSYNC and
VSYNC) are passed to an internal Logic Encoding Block to
encode the sync information as three discrete signals of
different voltage levels. Generally, in differential amplifiers an
external VREF pin is used to control the common mode level
of the differential output; in the case of the EL4543 the VREF
of each of the three internal amplifier channels receives a
signal from the Logic Encoding Block with encoded HSYNC
and VSYNC information. The final output consists of three
fully differential video signals, with sync encoded on the
common mode of each of the three RGB differential signals.
HSYNC and VSYNC can easily be separated from the
differential output signals, decoded and transmitted along
with the RGB video signals to the video monitor.
VSYNC
HSYNC
EN
+
INA
-
+
OUTA
-
VREF
RCM
LOGIC
DECODING
EN
+
-
+
INB
-
EN
+
-
+
OUTB
-
VREF
+
INC
-
EN
+
VREF
FIGURE 37. BLOCK DIAGRAM EL4543
11
The EL4543 encodes HSYNC and VSYNC signals on the
common mode output of the differential video signals; Red,
Green and Blue respectively. Data Sheet Figure 16, 17 and 18
clearly illustrate that the sum of the common mode voltages
results in a fixed average DC level with no AC content and
illustrates the logic levels. This eliminates EMI radiation into
any common mode signal along the twisted pairs of CAT 5
cable.
Extract Common Mode Sync and Decode HSYNC &
VSYNC
HSYNC and VSYNC can be regenerated from the Common
Mode sync output voltages. The relationships between
HSYNC, VSYNC and the 3 common mode levels are given by
Table 1. The common mode levels are easily separated from
the differential outputs of the EL4543 using this simple
resistor network at the cable receiver input of each
differential channel; see Figure 38.
Twisted Pair Termination
The schematic in Figure 38 illustrates a termination scheme
for 50Ω series termination and a 100Ω twisted pair cable.
Note RCM is the common mode termination to allow
measurement of VCM and should not be too small since it
loads the EL4543; a little over a 100Ω is recommended for
RCM.
TYPICAL EL4543 TERMINATION DRIVER
50Ω
+
50Ω
TWISTED
PAIR
ZO =100Ω
VREF
+
50Ω
VCM
50Ω
-
120Ω
(RCM: SHOULD BE >100Ω)
(FOR LOADING
CONSIDERATIONS)
FIGURE 38. TWISTED PAIR TERMINATION EL4543
Video Transmission
The EL4543 is a twisted pair differential line driver directed
at the transmission of Video Signals through cables up to
100 feet; however, as signal losses increase with
transmission line length the EL4543 will need additional
support to equalize video signals along longer twisted pair
transmission lines. A full solution to accomplish this is the
SXGA Video Transmission System presented in the EL4543
Data Sheet. Note the inclusion of the EL9110 for signal
equalization of up to 1000ft of CAT-5 cable and common
mode extraction; see Data Sheet for additional information
on the EL9110.
Long Distance Video Transmission
GCM
BCM
Sync Transmission
+
OUTC
-
The SXGA Video Transmission System makes it possible to
transmit Red, Green and Blue (RGB) video plus sync up to
1000 feet through CAT-5 cable. The input to the SXGA Video
Transmission System is the output of a video source
transmitting RGB video signals plus sync. The signals are
received initially by the EL4543; which converts the single
FN7325.5
October 26, 2005
EL4543
ended input RGB signals to three fully differential waveforms
with sync encoded on the discrete common modes of each
color channel and then drives the signals through a length of
CAT-5 cable. The signal is received by the EL9110, which
can provide 6-pole equalization for both high and low
frequency signal transmission line losses. Then the EL9110
converts the differential RGB video signals back into single
ended format while extracting the common mode component
for decoding. The single ended RGB signal is taken directly
from the output of the El9110 and is ready for the output
device. The Common Mode Decoder Circuit receives the
common mode signals directly from each of the three
EL9110's common mode output pin, decodes and transmits
HSYNC and VSYNC to the output device.
Sync Transmission
The EL4543 encodes HSYNC and VSYNC signals onto the
common mode output of the differential video signals; Red,
Green and Blue respectively. Data Sheet Figure 8 clearly
illustrates that the sum of the common mode voltages results
in a fixed DC level with no AC content; thus eliminating EMI
interference.
Output Drive Protection
The EL4543 has internal short circuit protection set typically
at 60mA. if the output is shorted for extended periods of time
the increased power dissipation will eventually destroy the
part. To realize maximum reliability the output current should
never exceed 60mA. The 50Ω series back load matching
resistor provides additional protection.
Supply Voltage
While the EL4543 can be operated on ±5V split rails, single
supply 0V to 5V is the most common usage. It is very
important to note that the input logic thresholds are relative
to the negative supply pin, and therefore single supply,
ground referenced logic will not work when driving the
EL4543 on split rails. The amplifiers have an input common
mode range from 0V to 3.5V with a 0V to 5V supply. The
common mode output DC level range is a linear function of
the power supply, see Data Sheet Figures 15, 16, 17 &18.
The common mode input switching threshold as well as the
Enable/Disable input is a linear function of the supply
voltage, see Data Sheet Figure 1.
Disable and Power Down
The EL4543 provides an enable disable function which
powers down, logic input high, in 900ns and powers up, logic
input low, in 212ns. Disabled the amplifiers supply current is
reduced to 1.8mA (Positive Supply) and 0mA (Negative
Supply). Note that Enable/Disable threshold is a linear
function of the supply voltage levels. The Enable/Disable
threshold voltage level is compatible with standard
TTL/CMOS and referenced to the lowest supply potential.
12
Proper Layout Technique
A critical concern with any PCB layout is the establishment
of a “healthy” ground plane. It is imperative to provide
ground planes terminated close to inputs to minimize input
capacitance. Additionally, the ground plane can be
selectively removed from inputs to prevent load and supply
currents from flowing near the input nodes.
In general the following guidelines apply to all PCB layout:
• Keep all traces as short as possible.
• Keep power supply bypass components as close to the
chip as possible - extremely close.
• Create a healthy ground with low impedance and
continuous ground pathways available to all grounded
components board-wide.
• In high frequency applications on multi-level boards try to
keep one level of board with continuous ground plane and
minimum via cutouts - providing it is affordable.
• Provide extremely short loops from power pin to ground.
• If it is affordable, a ferrite bead is always of benefit to
isolate device from Power Supply noise and the rest of the
circuit from the noise of the device.
Power Dissipation Calculation
When switching at high speeds, or driving heavy loads, the
EL4543 drive capability is ultimately limited by the rise in die
temperature brought about by internal power dissipation. For
reliable operation die temperature must be kept below TJMAX
(125°C). It is necessary to calculate the power dissipation for
a given application prior to selecting package type. Power
dissipation may be calculated:
4
2
2
PD = ( V S × I S ) × Σ ( C INT × V S × f ) + ( C L × V OUT × f )
1
where:
• VS is the total power supply to the EL4543 (from VS+ to VS-)
• VOUT is the swing on the output (VH - VL)
• CL is the load capacitance
• CINT is the internal load capacitance (80pF max)
• IS is the quiescent supply current (40mA max)
• f is frequency
Having obtained the application's power dissipation, the
maximum junction temperature can be calculated:
T JMAX = T MAX + Θ JA × PD
FN7325.5
October 26, 2005
EL4543
where:
converted to differential mode signals with HSYNC and
VSYNC encoded on the common-mode of the three
differential signals, respectively. The 50Ω output-terminated
EL4543 drives the differential RGB with sync encoded
common-mode to CAT-5 twisted pair cables. Note this
system, without signal frequency equalization, will
satisfactorily transmit along up to 200 feet of CAT-5 twistedpair. For longer cable lengths, frequency and gain
equalization to compensate for signal degradation is
recommended (EL9110) and a delay line technology
(EL9115) to adjust for phase mismatch between signals at
the receiving end.
• TJMAX is the maximum junction temperature (125°C)
• TMAX is the maximum ambient operating temperature
• PD is the power dissipation calculated above
• θJA is the thermal resistance, junction to ambient, of the
application (package + PCB combination). Refer to the
Package Power Dissipation curves.
Application Circuit
Video Transmission Along CAT-5 Cable
VGA input RGB plus sync is connected with 75Ω termination
to the inputs of the EL4543. Single-ended RGB video is
RED
EN
2
EL4543 QSOP
24
OUTA+
INA+
OUTA-
INA-
N.C.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
GREEN
4
N.C.
VS+
5
RVSYNC 1K
VSYNC
VS-
6
EL4543IU
3
HSYNC
RHSYNC 1K
7
N.C.
8
22
9
INB-
N.C.
10
11
BLUE
N.C.
OUTC+
INC+
OUTC-
INC-
N.C.
2
C34
0.1uf
+VS
R31 75
7
_
+VS
0.1uf
C35
3
18
RJOUTB+
49.9
6
_
4
16
15
RED
GREEN
C35a
200pF
EL8201IS
BLUE
U3
R30
2K
R29
2K
RJOUTB49.9
RJOUTC+
49.9
HSYNC
VSYNC
Blue Out Differential
14
13
5
VS-
Green Out Differential
17
RJC+ 75
12
8
VS+
19
RJB+ 75
INPUT
75
1
RJOUTA49.9
20
OUTB+
OUTB-
R32
Red Out Differential
21
N.C.
INB+
CAT2
RJOUTA+
49.9
23
RJA+ 75
8
7
6
5
4
3
2
1
CAT1
1
1
2
3
4
5
6
7
8
EL4543 & EL9110 Sync Extraction
RJOUTC49.9
OUTPUT
UJ1
-VS
+VS
DIODE D9
DIODE D10
DIODE D11
DIODE D12
-VS
+VS
+VS
-VS
DIODE D1
DIODE D2
DIODE D3
DIODE D4
-VS
-VS
+VS
DIODE D5
DIODE D6
C5
1uf
-VS
C17
0.1uf
C18
1uf
49.9
C24
51 C33
1uf
R33
NL
R29
NL
C25
VGAN
1
2
3
4
5
6
7
8
Ctrl-ref
Vctrl
Vinp
Vinm
Vsm
Cmout
Vgain
Logic-ref
1uf
C30
5
16
15
14
13
12
11
10
9
Cmext
Vsp
Enbl
Vspo
Vout
Vsmo
0V
X2
0.1uf
C31
0.1uf
C32
INDUCTOR 6
51
R32
0.1uf
R28
49.9
75 R25
RED
NL
R27
1K
R31
+VS
-VS
5
R23
Rred4
3000
R26
5
R25
R32
INDUCTOR3
C16
1uf
5
R12
NL
C23
R26
49.9
EL9110 GREEN B
R20
330
VGAN
INDUCTOR 4
75 R24
51
R22
NL
R18
R31
330
EL9110
0.1uf
NL
C14
16
15
14
13
12
11
10
9
Cmext
Vsp
Enbl
Vspo
Vout
Vsmo
0V
X2
C22
C13
R17
49.9
Ctrl-ref
Vctrl
Vinp
Vinm
Vsm
Cmout
Vgain
Logic-ref
Red In Differential
0.1uf
C11
0.1uf
49.9
+VS
GREEN
1
2
3
4
5
6
7
8
EL9110
51
R21
R29
INDUCTOR 1
C7
1uf
NL
R16
R30 1K
VadjRed
VCRTL
1uf
330
INDUCTOR 2
NL
C12
R15
49.9
EL9110 BLUE C
R9
330
C6
0.1uf
VGAN
16
15
14
13
12
11
10
9
Cmext
Vsp
Enbl
Vspo
Vout
Vsmo
0V
X2
C10
51
R11
NL
R4
NL
C3
Ctrl-ref
Vctrl
Vinp
Vinm
Vsm
Cmout
Vgain
Logic-ref
0.1uf
C4
0.1uf
1uf
C2
1
2
3
4
5
6
7
8
EL9110
51
R10
R5
R3
49.9
5
R14
BLUE
NL
R2
R6 1K
C20
VCRTL
Green InDifferential
1uf
75
R13
NL
C1
R1
49.9
DIODE D8
R19
R8
C9
Blue In Differential
49.9
-VS
DIODE D7
3000
R7
330
+VS
C21
0.1uf
VadjBlu
1uf
VCRTL
C15
+VS
+VS
EL9110 RED A
R27
330
C27
0.1uf
C26
1uf
C19
0.1uf
-VS
INDUCTOR 5
5
C28
1uf
R28
C29
0.1uf
C8
0.1uf
+VS
+VS
+VS
+VS
+VS
NL = Not Loaded
R33
3.6K
Inductor =Ferrite 68 Ohms
R34
3.6K
BANANA JACK
R35
3.6K
GND
BANANA JACK
R36
R37
VadjBlue
1K Pot
1K Pot
VGAN
R38
1K Pot
VCRTL
-VS
+ C36
+ C38
4.7uf
+VS
C37
4.7uf
R39
3.6K
0.1uF
C39
R40
1K Pot
0.1uF
VadjRed
-VS
BANANA JACK
13
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
FN7325.5
October 26, 2005
EL4543
EL4543/EL5375/EL8201 CAT-5 RGB +
Sync Video Transmission System
compensation network can be manipulated to provide some
measure of cable prop delay skew compensation for slight
differences in cable lengths between CAT-5 pairs. Cable
skew can best be done around the 300 ft range by under
compensating the shortest color pair (color on the left side of
a vertical line) and over compensate the longest color pair
(color on the right side of a vertical line). Around 450 ft only
the shortest color pair can be under compensated.
Introducing a low cost turn-key system for transmitting
component video over short to moderate CAT-5 cable
lengths (1 to 500 feet) with selectable cable loss and skew
compensation. Using only 3 of the 4 pairs in standard CAT-5
the 4th pair is available for audio, function control or data
transmission; an additional benefit.
The board for the driver and receiver should use strip lines
or strip line waveguides for the inputs and outputs of the
drivers and receivers. The 75Ω input and output strip lines
waveguide on 0.06 inch epoxy board with ground back plain
should be 0.016 inch wide with 0.01 inch space to ground
area around them. The diff pair strip line waveguides should
be two 0.045 inch 50Ω lines spaced 0.01 inch apart and
spaced 0.01 inch to ground area around them. This is a
general guide and size values may very for many reasons.
RGB video plus sync (5 channels) is received at the VGA
terminal and presented single ended to the EL4543. The
EL4543 converts single ended RGB into fully differential
signals on three twisted pairs. Sync is encoded on the three
RGB differential signals as differential common mode and
then drives the differential signals with encoded sync
through CAT-5 cable. The common mode of the signals is
extracted from the differential signals with a passive network
of resistors and passed to the EL8201 for sync decoding.
The differential signal is passed directly to the EL5375 where
it is amplified, converted back into single ended format.
Signal attenuation occurs in all transmission lines as a
function of increasing cable length; this application system
utilizes individual channel 2-pole compensation for cable
lengths of 150, 300 and 500 feet. Additionally, the
The receiver feedback and gain resistor network which goes
directly to the minus input should be connected very close
with minimal trace length and minimal capacitance to
ground. The ground plane on the backside of the board, in
back of these resistors and the minus input pin should be
removed as well.
Output +5V
R34
Open
R35
1
U2
REF1
NC
INP1
FB1
24
R40
2K
0
2
3
R36
Open
499
2K
499
R28
R28
2K
R24
R13
57
R25
Output +5V
R12
57
R37
4
5
INN1
OUT1
NC
NC
REF2
VSP
23
R41
2K
22
R14
49.9
Output +5V
R38
Open
499
R30
2K
2K
R26
R21
1K
R27
C2
0.1uF
499
R31
7
R39
8
9
20
11
Red In
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
24
OUTA+
INA-
N.C.
N.C.
VS+
VSYNC
VS-
22
5
R2 1K
6
7
HSYNC
OUTB+
INB+
OUTB-
C3
0.1uF
C1
0.1uf
20
18
9
10
Blue In
11
R5
INB-
N.C.
N.C.
OUTC+
INC+
OUTC-
16
R9
49.9
15
R10
49.9
INC-
NC
OUT3
R56
33K
R44
2K
R49
500
Compensation Control Switch
On
Off
1
12
2
11
3
10
4
9
5
8
6
7
R50
1K
15
14
150 Feet Comp
R57
300 Feet Comp
10K
C12
10p
C11
36p
R58
68K
R59
C13
68p
3.9K
C14
22p
R60
33K
SW DIP-6
13
R51
1K
R46
2K
R52
500
300 Feet Comp
R61 3.9K
C15 C16
68p 22p
150 Feet Comp
R63
R62
33K
C17
36p
10K
C18
10p
R64
68K
R63
75
R65
75
75
R66 75
R18
55
R19
55
R67 75
C19
0.1uF
1
R20
49.9
14
N.C.
13
2
R11
49.9
C4
0.1uF
R23
1K
C4a
220pF
VS+
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
OUTPUT
8
7
_
Output +5V
6
_
5
VS-
EL8201IS
U3
Input -5V
JB1
JB2
+VS In
-VS In
Csup1
4.7uF
JP+
JUMPER
+
+
JB3
C10
22p
R64
EL4543IU
Input +5V
C21
~4pF
16
R22
1K
Blue Out Differential
75
12
FB3
3.9K
17
R8
49.9
17
R4 75
INPUT
INN3
R55
C9
68p
19
N.C.
N.C.
EN
C22
~4pF
Green Out Differential
8
OUT2
INP3
R45
2K
R7
49.9
21
R3 1K
Green In
FB2
REF3
R17
49.9
Input +5V
4
NC
300 Feet Comp
R54
68K
R43
2K
18Output -5V
EL5375
23
OUTA-
NC
10K
C6
0.1uF
19
R6
49.9
Red Out Differential
INA+
INN2
150 Feet Comp
C7 C8
36p 10p
499
3
EL4543 QSOP
EN
12
499
R33
2
R16
57
R32
1
R1
75
VSN
R48
1K
R53
0
10
R15
57
INP2
R47
500
C5
0.1uF
0
6
C20
~4pF
21
Output +5V
Csup2
4.7uF
Ground
JUMPER
JPJUMPER
Output +5V
JB4
2
2
1
1
2
1
GND
Output -5V
JB5
-VS Out
+ Csup3
4.7uF
+
+VS Out
Csup4
4.7uF
JB6
14
8
7
6
5
4
3
2
1
1
2
3
4
5
6
7
8
GND
OUTPUT
INPUT
FN7325.5
October 26, 2005
EL4543
QSOP Package Outline Drawing
15
FN7325.5
October 26, 2005
EL4543
QFN Package Outline Drawing
NOTE: The package drawings shown here may not be the latest version. To check the latest revision, please refer to the Intersil website at
http://www.intersil.com/design/packages/index.asp
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
16
FN7325.5
October 26, 2005
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