INTERSIL EL5292A

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Data Sheet
Dual 600MHz Current Feedback Amplifier
with Enable
The EL5292 and EL5292A represent
dual current feedback amplifiers with a
very high bandwidth of 600MHz. This
makes these amplifiers ideal for today’s high speed video
and monitor applications.
With a supply current of just 6mA per amplifier and the ability
to run from a single supply voltage from 5V to 10V, these
amplifiers are also ideal for hand held, portable or battery
powered equipment.
EL5292, EL5292A
January 22, 2004
FN7192
Features
• 600MHz -3dB bandwidth
• 6mA supply current (per amplifier)
• Single and dual supply operation, from 5V to 10V
• Fast enable/disable (EL5292A only)
• Single (EL5192) and triple (EL5392) available
• High speed, 1GHz product available (EL5191)
• Low power, 4mA, 300MHz product available (EL5193,
EL5293, and EL5393)
The EL5292A also incorporates an enable and disable
function to reduce the supply current to 100µA typical per
amplifier. Allowing the CE pin to float or applying a low logic
level will enable the amplifier.
Applications
The EL5292 is offered in the industry-standard 8-pin SO
package and the space-saving 8-pin MSOP package. The
EL5292A is available in a 10-pin MSOP package and all
operate over the industrial temperature range of -40°C to
+85°C.
• RGB amplifiers
• Video amplifiers
• Cable drivers
• Test equipment
• Instrumentation
• Current to voltage converters
Pinouts
EL5292
(8-PIN SO, MSOP)
TOP VIEW
Ordering Information
PACKAGE
TAPE &
REEL
PKG. NO.
EL5292CS
8-Pin SO
-
MDP0027
EL5292CS-T7
8-Pin SO
7”
MDP0027
EL5292CS-T13
8-Pin SO
13”
MDP0027
EL5292CY
8-Pin MSOP
-
MDP0043
EL5292CY-T7
8-Pin MSOP
7”
MDP0043
EL5292CY-T13
8-Pin MSOP
13”
MDP0043
EL5292ACY
10-Pin MSOP
-
MDP0043
EL5292ACY-T7
10-Pin MSOP
7”
MDP0043
EL5292ACY-T13
10-Pin MSOP
13”
MDP0043
PART NUMBER
OUTA 1
INA- 2
8 VS+
+
7 OUTB
INA+ 3
6 INB+
VS- 4
5 INB+
EL5292A
(10-PIN MSOP)
TOP VIEW
INA+ 1
CEA 2
10 INA+
8 VS+
VS- 3
CEB 4
9 OUTA
+
-
7 OUTB
6 INB-
INB+ 5
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2004. All Rights Reserved. Elantec is a registered trademark of Elantec Semiconductor, Inc.
All other trademarks mentioned are the property of their respective owners.
EL5292, EL5292A
Absolute Maximum Ratings (TA = 25°C)
Supply Voltage between VS+ and VS- . . . . . . . . . . . . . . . . . . . . . 11V
Maximum Continuous Output Current . . . . . . . . . . . . . . . . . . . 50mA
Operating Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . 125°C
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Curves
Pin Voltages. . . . . . . . . . . . . . . . . . . . . . . . . VS- -0.5V to VS+ +0.5V
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . -65°C to +150°C
Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°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
Electrical Specifications
VS+ = +5V, VS- = -5V, RF = 750Ω for AV = 1, RF = 375Ω for AV = 2, RL = 150Ω, TA = 25°C unless otherwise
specified.
PARAMETER
DESCRIPTION
CONDITIONS
MIN
TYP
MAX
UNIT
AC PERFORMANCE
BW
-3dB Bandwidth
AV = +1
600
MHz
AV = +2
300
MHz
25
MHz
2300
V/µs
BW1
0.1dB Bandwidth
SR
Slew Rate
VO = -2.5V to +2.5V, AV = +2
tS
0.1% Settling Time
VOUT = -2.5V to +2.5V, AV = -1
9
ns
CS
Channel Separation
f = 5MHz
60
dB
eN
Input Voltage Noise
4.1
nV/√Hz
iN-
IN- Input Current Noise
20
pA/√Hz
iN+
IN+ Input Current Noise
50
pA/√Hz
dG
Differential Gain Error (Note 1)
AV = +2
0.015
%
dP
Differential Phase Error (Note 1)
AV = +2
0.04
°
2000
DC PERFORMANCE
VOS
Offset Voltage
TCVOS
Input Offset Voltage Temperature
Coefficient
ROL
Transimpediance
-10
Measured from TMIN to TMAX
1
10
mV
5
µV/°C
200
400
kΩ
INPUT CHARACTERISTICS
CMIR
Common Mode Input Range
±3
±3.3
V
CMRR
Common Mode Rejection Ratio
42
50
dB
+IIN
+ Input Current
-60
3
60
µA
-IIN
- Input Current
-35
4
35
µA
RIN
Input Resistance
37
kΩ
CIN
Input Capacitance
0.5
pF
OUTPUT CHARACTERISTICS
RL = 150Ω to GND
±3.4
±3.7
V
RL = 1kΩ to GND
±3.8
±4.0
V
Output Current
RL = 10Ω to GND
95
120
mA
ISON
Supply Current - Enabled
No load, VIN = 0V
5
6
7.5
mA
ISOFF
Supply Current - Disabled
No load, VIN = 0V
100
150
µA
VO
IOUT
Output Voltage Swing
SUPPLY
2
EL5292, EL5292A
Electrical Specifications
VS+ = +5V, VS- = -5V, RF = 750Ω for AV = 1, RF = 375Ω for AV = 2, RL = 150Ω, TA = 25°C unless otherwise
specified. (Continued)
PARAMETER
DESCRIPTION
CONDITIONS
MIN
TYP
75
PSRR
Power Supply Rejection Ratio
DC, VS = ±4.75V to ±5.25V
55
-IPSR
- Input Current Power Supply Rejection
DC, VS = ±4.75 to ±5.25V
-2
MAX
UNIT
dB
2
µA/V
ENABLE (EL5292A ONLY)
tEN
Enable Time
40
ns
tDIS
Disable Time
600
ns
IIHCE
CE Pin Input High Current
CE = VS+
0.8
6
µA
IILCE
CE Pin Input Low Current
CE = VS-
0
-0.1
µA
VIHCE
CE Input High Voltage for Power-down
VILCE
CE Input Low Voltage for Power-down
NOTE:
1. Standard NTSC test, AC signal amplitude = 286mVP-P, f = 3.58MHz
3
VS+ - 1
V
VS+ - 3
V
EL5292, EL5292A
Typical Performance Curves
Non-Inverting Frequency Response (Gain)
Non-Inverting Frequency Response (Phase)
6
90
AV=2
0
-2
-90
AV=1
AV=2
Phase (°)
Normalized Magnitude (dB)
AV=1
2
AV=5
-6
AV=5
AV=10
-180
AV=10
-10
-270
-14
1M
RF=750Ω
RL=150Ω
10M
100M
-360
1M
1G
RF=750Ω
RL=150Ω
10M
Frequency (Hz)
Inverting Frequency Response (Gain)
90
AV=-1
2
AV=-2
AV=-1
0
Phase (°)
-2
AV=-5
-6
-10
-90
AV=-2
AV=-5
-180
-270
-14
1M
RF=375Ω
RL=150Ω
10M
100M
-360
1M
1G
RF=375Ω
RL=150Ω
10M
Frequency (Hz)
100M
Frequency Response for Various CIN-
Frequency Response for Various RL
6
RL=150Ω
Normalized Magnitude (dB)
2pF added
6
1pF added
2
-2
-6
-10
1M
1G
Frequency (Hz)
10
Normalized Magnitude (dB)
1G
Inverting Frequency Response (Phase)
6
Normalized Magnitude (dB)
100M
Frequency (Hz)
0pF added
AV=2
RF=375Ω
RL=150Ω
10M
100M
Frequency (Hz)
4
1G
RL=100Ω
2
RL=500Ω
-2
-6
-10
-14
1M
AV=2
RF=375Ω
10M
100M
Frequency (Hz)
1G
EL5292, EL5292A
Typical Performance Curves
(Continued)
Frequency Response for Various CL
Frequency Response for Various RF
14
6
Normalized Magnitude (dB)
Normalized Magnitude (dB)
250Ω
10
12pF added
6
8pF added
2
-2
-6
1M
0pF added
AV=2
RF=375Ω
RL=150Ω
10M
100M
475Ω
-2
620Ω
-6
750Ω
-10
-14
1M
1G
AV=2
RG=RF
RL=150Ω
10M
Frequency (Hz)
100M
1G
Frequency (Hz)
Group Delay vs Frequency
Frequency Response for Various Common-Mode
Input Voltages
3.5
6
2.5
Normalized Magnitude (dB)
3
Group Delay (ns)
375Ω
2
AV=2
RF=375Ω
2
1.5
1
AV=1
RF=750Ω
0.5
0
1M
10M
100M
VCM=3V
-2
VCM=-3V
-6
-10
-14
1M
1G
VCM=0V
2
AV=2
RF=375Ω
RL=150Ω
10M
Frequency (Hz)
100M
1G
Frequency (Hz)
Transimpedance (ROL) vs Frequency
PSRR and CMRR vs Frequency
10M
20
0
Phase
100k
-180
10k
-270
Gain
1k
PSRR/CMRR (dB)
0
-90
Phase (°)
Magnitude (Ω)
1M
PSRR+
-20
PSRR-40
-60
CMRR
-360
100
1k
10k
100k
1M
10M
Frequency (Hz)
5
100M
1G
-80
10k
100k
1M
10M
Frequency (Hz)
100M
1G
EL5292, EL5292A
Typical Performance Curves
(Continued)
-3dB Bandwidth vs Supply Voltage for Inverting
Gains
-3dB Bandwidth vs Supply Voltage for NonInverting Gains
800
350
300
600
-3dB Bandwidth (MHz)
-3dB Bandwidth (MHz)
RF=750Ω
RL=150Ω
AV=1
400
AV=2
200
AV=5
AV=10
AV=-1
250
AV=-2
200
AV=-5
150
100
50
0
RF=375Ω
RL=150Ω
0
5
6
8
7
9
5
10
6
Peaking vs Supply Voltage for Non-Inverting Gains
9
10
4
RF=750Ω
RL=150Ω
Peaking (dB)
3
2
1
RF=375Ω
RL=150Ω
AV=-1
AV=1
3
Peaking (dB)
8
Peaking vs Supply Voltage for Inverting Gains
4
AV=-2
2
1
AV=2
AV=10
AV=-5
0
0
5
6
7
8
9
5
10
Total Supply Voltage (V)
-3dB Bandwidth vs Temperature for Non-Inverting
Gains
7
8
9
10
-3dB Bandwidth vs Temperature for Inverting
Gains
500
RF=750Ω
RL=150Ω
AV=1
-3dB Bandwidth (MHz)
1200
6
Total Supply Voltage (V)
1400
-3dB Bandwidth (MHz)
7
Total Supply Voltage (V)
Total Supply Voltage (V)
1000
800
600
400
AV=2
AV=5
AV=10
400
300
RF=375Ω
RL=150Ω
AV=-1
AV=-2
200
AV=-5
100
200
0
-40
10
60
110
Ambient Temperature (°C)
6
160
0
-40
10
60
110
Ambient Temperature (°C)
160
EL5292, EL5292A
Typical Performance Curves
(Continued)
Peaking vs Temperature
Voltage and Current Noise vs Frequency
2
1k
Peaking (dB)
1.5
Voltage Noise (nV/√Hz)
Current Noise (pA/√Hz)
RL=150Ω
AV=1
1
AV=-1
0.5
AV=-2
0
100
in+
in-
10
en
AV=2
-0.5
-50
0
-50
50
1
100
100
1k
Ambient Temperature (°C)
10
10
8
1
0.1
0.01
0.001
100
10M
6
4
2
0
1k
10k
1M
100k
10M
Frequency (Hz)
100M
1G
0
2
4
6
8
Supply Voltage (V)
10
12
Two-Tone 3rd Order
Input Referred Intermodulation Intercept (IIP3)
2nd and 3rd Harmonic Distortion vs Frequency
-20
30
-40
-50
Input Power Intercept (dBm)
AV=+2
VOUT=2VP-P
RL=100Ω
-30
Harmonic Distortion (dBc)
1M
Supply Current vs Supply Voltage
100
Supply Current (mA)
Output Impedance (Ω)
Closed Loop Output Impedance vs Frequency
10k
100k
Frequency (Hz)
2nd Order
Distortion
-60
-70
3rd Order
Distortion
-80
-90
-100
1
10
Frequency (MHz)
7
100
AV=+2
RL=150Ω
25
20
15
10
5
0
-5
-10
-15
10
AV=+2
RL=100Ω
100
Frequency (MHz)
200
EL5292, EL5292A
Typical Performance Curves
(Continued)
Differential Gain/Phase vs DC Input
Voltage at 3.58MHz
Differential Gain/Phase vs DC Input
Voltage at 3.58MHz
0.03
0.03
AV=2
RF=RG=375Ω
RL=150Ω
dG (%) or dP (°)
0.01
dP
0.01
0
dG
-0.01
-0.02
0
-0.03
-0.04
-0.05
0
0.5
dG
-0.02
-0.04
-0.5
-0.06
-1
1
dP
-0.01
-0.03
-0.05
-1
AV=1
RF=750Ω
RL=500Ω
0.02
dG (%) or dP (°)
0.02
-0.5
DC Input Voltage
Output Voltage Swing vs Frequency
THD<1%
0.5
1
Output Voltage Swing vs Frequency
THD<0.1%
9
10
RL=500Ω
8
7
Output Voltage Swing (VPP)
Output Voltage Swing (VPP)
0
DC Input Voltage
RL=150Ω
6
5
4
3
2
1
AV=2
0
RL=500Ω
8
RL=150Ω
6
4
2
AV=2
0
1
10
Frequency (MHz)
100
1
Small Signal Step Response
10
Frequency (MHz)
Large Signal Step Response
VS=±5V
RL=150Ω
AV=2
RF=RG=375Ω
200mV/div
VS=±5V
RL=150Ω
AV=2
RF=RG=375Ω
1V/div
10ns/div
8
100
10ns/div
EL5292, EL5292A
Typical Performance Curves
(Continued)
Settling Time vs Settling Accuracy
Transimpedance (RoI) vs Temperature
25
500
AV=2
RF=RG=375Ω
RL=150Ω
VSTEP=5VP-P output
450
15
RoI (kΩ)
Settling Time (ns)
20
10
400
350
5
0
0.01
0.1
300
-40
1
10
Settling Accuracy (%)
PSRR and CMRR vs Temperature
110
160
110
160
ICMR and IPSR vs Temperature
90
2.5
80
PSRR
2
ICMR/IPSR (µA/V)
70
PSRR/CMRR (dB)
60
Die Temperature (°C)
60
CMRR
50
40
30
ICMR+
1.5
1
IPSR
0.5
0
ICMR-
-0.5
20
10
-40
10
60
110
-1
-40
160
10
Die Temperature (°C)
60
Die Temperature (°C)
Offset Voltage vs Temperature
Input Current vs Temperature
3
60
40
Input Current (µA)
VOS (mV)
2
1
0
20
IB0
-20
IB+
-40
-1
-60
-2
-40
10
60
Die Temperature (°C)
9
110
160
-80
-40
10
60
Temperature (°C)
110
160
EL5292, EL5292A
Typical Performance Curves
(Continued)
Positive Input Resistance vs Temperature
Supply Current vs Temperature
50
8
45
7
Supply Current (mA)
40
RIN+ (kΩ)
35
30
25
20
15
10
6
5
4
3
2
1
5
0
-40
60
10
110
0
-40
160
60
10
Temperature (°C)
110
160
Temperature (°C)
Positive Output Swing vs Temperature for Various
Loads
Negative Output Swing vs Temperature for Various
Loads
4.2
-3.5
4.1
-3.6
150Ω
1kΩ
-3.7
VOUT (V)
VOUT (V)
4
3.9
3.8
3.7
-3.8
-3.9
1kΩ
-4
150Ω
3.6
-4.1
3.5
-40
10
50
110
-4.2
-40
160
10
60
Temperature (°C)
110
160
110
160
Temperature (°C)
Output Current vs Temperature
Slew Rate vs Temperature
135
4600
4400
4200
Sink
Slew Rate (V/µS)
IOUT (mA)
130
125
Source
120
4000
3800
3600
3400
3200
115
-40
10
60
Die Temperature (°C)
10
110
160
3000
-40
AV=2
RF=RG=375Ω
RL=150Ω
10
60
Die Temperature (°C)
EL5292, EL5292A
Typical Performance Curves
(Continued)
Channel-to-Channel Isolation vs Frequency
Enable Response
0
Gain (dB)
-20
500mV/div
-40
-60
5V/div
-80
-100
100k
1M
10M
100M
400M
20ns/div
Frequency (Hz)
Package Power Dissipation vs Ambient Temperature
JEDEC JESD51-3 Low Effective Thermal Conductivity
Test Board
Disable Response
0.7
8
0.5
0
16
/W
°C
500mV/div
SO
Power Dissipation (W)
0.6 625mW
0.4
0.3
0.2
0.1
5V/div
0
0
400ns/div
25
50
75 85 100
Ambient Temperature (°C)
0.6
Package Power Dissipation vs Ambient Temperature
JEDEC JESD51-3 Low Effective Thermal Conductivity
Test Board
486mW
Power Dissipation (W)
0.5
M
SO
P8
20
/1
0
6°
C/
W
0.4
0.3
0.2
0.1
0
0
25
50
75 85
Ambient Temperature (°C)
11
100
125
125
150
EL5292, EL5292A
Pin Descriptions
8-PIN
SO/MSOP
10-PIN
MSOP
PIN NAME
1
9
OUTA
FUNCTION
EQUIVALENT CIRCUIT
Output, channel A
VS+
OUT
VSCircuit 1
2
10
INA-
Inverting input, channel A
VS+
IN+
IN-
VSCircuit 2
3
1
INA+
Non-inverting input, channel A
2
CEA
Chip enable, channel A
(see circuit 2)
VS+
CE
VSCircuit 3
4
3
VS-
Negative supply
4
CEB
Chip enable, channel B
(see circuit 3)
5
5
INB+
Non-inverting input, channel B
(see circuit 2)
6
6
INB-
Inverting input, channel B
(see circuit 2)
7
7
OUTB
Output, channel B
(see circuit 1)
8
8
VS+
Positive supply
Applications Information
Product Description
The EL5292 is a current-feedback operational amplifier that
offers a wide -3dB bandwidth of 600MHz and a low supply
current of 6mA per amplifier. The EL5292 works with supply
voltages ranging from a single 5V to 10V and they are also
capable of swinging to within 1V of either supply on the
output. Because of their current-feedback topology, the
EL5292 does not have the normal gain-bandwidth product
associated with voltage-feedback operational amplifiers.
Instead, its -3dB bandwidth to remain relatively constant as
closed-loop gain is increased. This combination of high
bandwidth and low power, together with aggressive pricing
make the EL5292 the ideal choice for many low-power/highbandwidth applications such as portable, handheld, or
battery-powered equipment.
12
For varying bandwidth needs, consider the EL5191 with
1GHz on a 9mA supply current or the EL5193 with 300MHz
on a 4mA supply current. Versions include single, dual, and
triple amp packages with 5-pin SOT23, 16-pin QSOP, and 8pin or 16-pin SO outlines.
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high frequency device, good printed circuit
board layout is necessary for optimum performance. Low
impedance ground plane construction is essential. Surface
mount components are recommended, but if leaded
components are used, lead lengths should be as short as
possible. The power supply pins must be well bypassed to
reduce the risk of oscillation. The combination of a 4.7µF
tantalum capacitor in parallel with a 0.01µF capacitor has
been shown to work well when placed at each supply pin.
EL5292, EL5292A
For good AC performance, parasitic capacitance should be
kept to a minimum, especially at the inverting input. (See the
Capacitance at the Inverting Input section) Even when
ground plane construction is used, it should be removed
from the area near the inverting input to minimize any stray
capacitance at that node. Carbon or Metal-Film resistors are
acceptable with the Metal-Film resistors giving slightly less
peaking and bandwidth because of additional series
inductance. Use of sockets, particularly for the SO package,
should be avoided if possible. Sockets add parasitic
inductance and capacitance which will result in additional
peaking and overshoot.
Disable/Power-Down
The EL5292A amplifier can be disabled placing its output in
a high impedance state. When disabled, the amplifier supply
current is reduced to < 300µA. The EL5292A is disabled
when its CE pin is pulled up to within 1V of the positive
supply. Similarly, the amplifier is enabled by floating or
pulling its CE pin to at least 3V below the positive supply. For
±5V supply, this means that an EL5292A amplifier will be
enabled when CE is 2V or less, and disabled when CE is
above 4V. Although the logic levels are not standard TTL,
this choice of logic voltages allows the EL5292A to be
enabled by tying CE to ground, even in 5V single supply
applications. The CE pin can be driven from CMOS outputs.
Capacitance at the Inverting Input
Any manufacturer’s high-speed voltage- or current-feedback
amplifier can be affected by stray capacitance at the
inverting input. For inverting gains, this parasitic capacitance
has little effect because the inverting input is a virtual
ground, but for non-inverting gains, this capacitance (in
conjunction with the feedback and gain resistors) creates a
pole in the feedback path of the amplifier. This pole, if low
enough in frequency, has the same destabilizing effect as a
zero in the forward open-loop response. The use of largevalue feedback and gain resistors exacerbates the problem
by further lowering the pole frequency (increasing the
possibility of oscillation.)
The EL5292 has been optimized with a 375Ω feedback
resistor. With the high bandwidth of these amplifiers, these
resistor values might cause stability problems when
combined with parasitic capacitance, thus ground plane is
not recommended around the inverting input pin of the
amplifier.
Feedback Resistor Values
The EL5292 has been designed and specified at a gain of +2
with RF approximately 375Ω. This value of feedback resistor
gives 300MHz of -3dB bandwidth at AV=2 with 2dB of
peaking. With AV=-2, an RF of 375Ω gives 275MHz of
bandwidth with 1dB of peaking. Since the EL5292 is a
current-feedback amplifier, it is also possible to change the
value of RF to get more bandwidth. As seen in the curve of
Frequency Response for Various RF and RG, bandwidth and
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peaking can be easily modified by varying the value of the
feedback resistor.
Because the EL5292 is a current-feedback amplifier, its
gain-bandwidth product is not a constant for different closedloop gains. This feature actually allows the EL5292 to
maintain about the same -3dB bandwidth. As gain is
increased, bandwidth decreases slightly while stability
increases. Since the loop stability is improving with higher
closed-loop gains, it becomes possible to reduce the value
of RF below the specified 375Ω and still retain stability,
resulting in only a slight loss of bandwidth with increased
closed-loop gain.
Supply Voltage Range and Single-Supply
Operation
The EL5292 has been designed to operate with supply
voltages having a span of greater than 5V and less than 10V.
In practical terms, this means that the EL5292 will operate
on dual supplies ranging from ±2.5V to ±5V. With singlesupply, the EL5292 will operate from 5V to 10V.
As supply voltages continue to decrease, it becomes
necessary to provide input and output voltage ranges that
can get as close as possible to the supply voltages. The
EL5292 has an input range which extends to within 2V of
either supply. So, for example, on ±5V supplies, the EL5292
has an input range which spans ±3V. The output range of the
EL5292 is also quite large, extending to within 1V of the
supply rail. On a ±5V supply, the output is therefore capable
of swinging from--4V to +4V. Single-supply output range is
larger because of the increased negative swing due to the
external pull-down resistor to ground.
Video Performance
For good video performance, an amplifier is required to
maintain the same output impedance and the same
frequency response as DC levels are changed at the output.
This is especially difficult when driving a standard video load
of 150Ω, because of the change in output current with DC
level. Previously, good differential gain could only be
achieved by running high idle currents through the output
transistors (to reduce variations in output impedance.)
These currents were typically comparable to the entire 6mA
supply current of each EL5292 amplifier. Special circuitry
has been incorporated in the EL5292 to reduce the variation
of output impedance with current output. This results in dG
and dP specifications of 0.015% and 0.04°, while driving
150Ω at a gain of 2.
Video performance has also been measured with a 500Ω
load at a gain of +1. Under these conditions, the EL5292 has
dG and dP specifications of 0.03% and 0.05°, respectively.
Output Drive Capability
In spite of its low 6mA of supply current, the EL5292 is
capable of providing a minimum of ±95mA of output current.
With a minimum of ±95mA of output drive, the EL5292 is
EL5292, EL5292A
capable of driving 50Ω loads to both rails, making it an
excellent choice for driving isolation transformers in
telecommunications applications.
Driving Cables and Capacitive Loads
When used as a cable driver, double termination is always
recommended for reflection-free performance. For those
applications, the back-termination series resistor will
decouple the EL5292 from the cable and allow extensive
capacitive drive. However, other applications may have high
capacitive loads without a back-termination resistor. In these
applications, a small series resistor (usually between 5Ω and
50Ω) can be placed in series with the output to eliminate
most peaking. The gain resistor (RG) can then be chosen to
make up for any gain loss which may be created by this
additional resistor at the output. In many cases it is also
possible to simply increase the value of the feedback
resistor (RF) to reduce the peaking.
PDMAX for each amplifier can be calculated as follows:
V OUTMAX
PD MAX = ( 2 × V S × I SMAX ) + ( V S - V OUTMAX ) × ---------------------------R
L
where:
VS = Supply voltage
ISMAX = Maximum supply current of 1A
VOUTMAX = Maximum output voltage (required)
RL = Load resistance
Current Limiting
The EL5292 has no internal current-limiting circuitry. If the
output is shorted, it is possible to exceed the Absolute
Maximum Rating for output current or power dissipation,
potentially resulting in the destruction of the device.
Power Dissipation
With the high output drive capability of the EL5292, it is
possible to exceed the 125°C Absolute Maximum junction
temperature under certain very high load current conditions.
Generally speaking when RL falls below about 25Ω, it is
important to calculate the maximum junction temperature
(TJMAX) for the application to determine if power supply
voltages, load conditions, or package type need to be
modified for the EL5292 to remain in the safe operating area.
These parameters are calculated as follows:
T JMAX = T MAX + ( θ JA × n × PD MAX )
where:
TMAX = Maximum ambient temperature
θJA = Thermal resistance of the package
n = Number of amplifiers in the package
PDMAX = Maximum power dissipation of each amplifier in
the package
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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
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