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EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Features
* * * * * * * * Gain selectable (+1, -1, +2) 400MHz -3dB BW (AV = 1, 2) 9mA supply current Fast enable/disable (EL5196AC only) Single and dual supply operation, from 5V to 10V Available in SOT23 packages Triple (EL5396C) available 200MHz, 4mA product available (EL5197C, EL5397C)
General Description
The EL5196C and the EL5196AC are fixed gain amplifiers with a bandwidth of 400MHz, making these amplifiers ideal for today's high speed video and monitor applications. These amplifiers feature internal gain setting resistors and can be configured in a gain of +1, -1 or +2. The same bandwidth is seen in both gain-of-1 and gain-of-2 applications. The EL5196AC also incorporates an enable and disable function to reduce the supply current to 100A typical per amplifier. Allowing the CE pin to float or applying a low logic level will enable the amplifier. The EL5196C is offered in the 5-pin SOT23 package and the EL5196AC is available in the 6-pin SOT23 as well as the industrystandard 8-pin SO packages. Both operate over the industrial temperature range of -40C to +85C.
Applications
* * * * * * Video amplifiers Cable drivers RGB amplifiers Test equipment Instrumentation Current to voltage converters
Pin Configurations
NC 1 IN- 2 IN+ 3
Outline # MDP0038 MDP0038 MDP0038 MDP0038 MDP0027 MDP0027 MDP0027
8 CE + 6 OUT 5 NC EL5196ACS (8-Pin SO) 7 VS+
Ordering Information
Part No EL5196CW-T7 EL5196CW-T13 EL5196ACW-T7 EL5196ACW-T13 EL5196ACS EL5196ACS-T7 EL5196ACS-T13 Package 5-Pin SOT23 5-Pin SOT23 6-Pin SOT23 6-Pin SOT23 8-Pin SO 8-Pin SO 8-Pin SO Tape & Reel 7" 13" 7" 13" 7" 13"
VS- 4
OUT 1 VS- 2 + IN+ 3 EL5196ACW (6-Pin SOT23) -
6 VS+ 5 CE 4 IN-
OUT 1 VS- 2 + IN+ 3 EL5196CW (5-Pin SOT23) -
5 VS+
4 IN-
February 11, 2002
Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a "controlled document". Current revisions, if any, to these specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.
(c) 2002 Elantec Semiconductor, Inc.
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Absolute Maximum Ratings (T
A=
25C)
Values beyond absolute maximum ratings can cause the device to be prematurely damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. Supply Voltage between VS+ and VS11V Maximum Continuous Output Current 50mA
Operating Junction Temperature Power Dissipation Pin Voltages Storage Temperature Operating Temperature
125C See Curves VS- - 0.5V to VS+ +0.5V -65C to +150C -40C to +85C
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 = T C = TA .
Electrical Characteristics
VS+ = +5V, VS- = -5V, RL = 150, T A = 25C unless otherwise specified. Parameter AC Performance BW -3dB Bandwidth AV = +1 AV = -1 AV = +2 BW1 SR tS eN iN iN + dG dP VOS TC VOS AE RF, RG CMIR +IIN -IIN RIN CIN VO IOUT Supply ISON ISOFF PSRR -IPSR Supply Current - Enabled Supply Current - Disabled Power Supply Rejection Ratio - Input Current Power Supply Rejection No load, VIN = 0V No load, VIN = 0V DC, VS = 4.75V to 5.25V DC, VS = 4.75V to 5.25V 55 -2 8 9 100 75 2 11 150 mA A dB A/V 0.1dB Bandwidth Slew Rate 0.1% Settling Time Input Voltage Noise IN- Input Current Noise IN+ Input Current Noise Differential Gain Error Differential Phase Error Offset Voltage Input Offset Voltage Temperature Coefficient Gain Error Internal RF and RG Common Mode Input Range + Input Current - Input Current Input Resistance Input Capacitance Output Voltage Swing Output Current RL = 150 to GND RL = 1k to GND RL = 10 to GND 3.4V 3.8V 95 at IN + Measured from TMIN to TMAX VO = -3V to +3V -2 320 3V -120 -40
[1] [1]
Description
Conditions
Min
Typ 400 400 400 35
Max
Unit MHz MHz MHz MHz V/s ns nV/Hz pA/Hz pA/Hz %
VO = -2.5V to +2.5V, AV = +2 VOUT = -2.5V to +2.5V, AV = -1
2400
2900 9 3.8 25 55
AV = +2 AV = +2 -15
0.035 0.04 1 5 1.3 400 3.3V 40 4 27 0.5 3.7V 4.0V 120 120 40 2 480 15
DC Performance mV V/C % V A A k pF V V mA
Input Characteristics
Output Characteristics
2
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Electrical Characteristics
VS+ = +5V, VS- = -5V, RL = 150, T A = 25C unless otherwise specified. Parameter Enable (EL5196AC only) tEN tDIS IIHCE IILCE VIHCE VILCE Enable Time Disable Time CE Pin Input High Current CE Pin Input Low Current CE Input High Voltage for Power-down CE Input Low Voltage for Power-down CE = VS+ CE = VSV S+ - 1 VS+ - 3 40 600 0.8 0 6 -0.1 ns ns A A V V Description Conditions Min Typ Max Unit
1. Standard NTSC test, AC signal amplitude = 286mVP-P , f = 3.58MHz
3
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Frequency Response (Gain) SOT23 Package 6 AV=-1 90
Frequency Response (Phase) SOT23 Package
Normalized Magnitude (dB)
2
0 All Gains Phase ()
-2
AV=2 AV=1
-90
-6
-180
-10 RL=150 -14 1M 10M 100M Frequency (Hz) Frequency Response for Various CL 14 AV=2 RL=150 1G
-270 RL=150 -360 1M 10M 100M Frequency (Hz) Group Delay vs Frequency, All Gains -3.5 RL=150 -3 8pF added 4pF added Delay (ns) -2.5 -2 -1.5 -1 All Gains 1G
Normalized Magnitude (dB)
10
6
2
-2
0pF added -0.5
-6 1M
10M
100M Frequency (Hz)
1G
0 1M
10M
100M Frequency (Hz)
1G
Frequency Response for Various Common-Mode Input Voltages 6 VCM=3V Normalized Magnitude (dB) 2 Magnitude () 1M 10M
Transimpedance (ROL) vs Frequency
0 Phase -90 Phase ()
-2
100k -180 10k Gain -270
-6
VCM=-3V
-10 AV=2 RL=150 -14 1M 10M VCM=0V 100M Frequency (Hz) 1G
1k -360 100 1k 10k 100k 1M 10M Frequency (Hz) 100M 1G
4
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
PSRR and CMRR vs Frequency 20 450
-3dB Bandwidth vs Supply Voltage
AV=1 0 PSRR/CMRR (dB) -3dB Bandwidth (MHz) PSRR+
AV=-1
400
-20 PSRR1 -40 CMRR
AV=2
350
-60
RL=150 -80 10k 300 100k 1M 10M Frequency (Hz) 100M 1G 5 6 7 8 9 10 Total Supply Voltage (V) -3dB Bandwidth vs Temperature 600 500 -3dB Bandwidth (MHz) 3 Peaking (dB) AV=1 2 AV=2 1 RL=150 0 5 6 7 8 9 10 Total Supply Voltage (V) Peaking vs Temperature 0.6 RL=150 0.5 0.4 0.3 0.2 0.1 0 -40 1 100 Voltage Noise (nV/Hz) Current Noise (pA/Hz) 100 inin+ 1k 0 -40 AV =-1 400 300 200 100 RL=150 10 60 Ambient Temperature (C) Voltage and Current Noise vs Frequency 110 160
Peaking vs Supply Voltage 4
Peaking (dB)
10
en
10
60 Ambient Temperature (C)
110
160
1k
10k 100k Frequency (Hz)
1M
10M
5
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Closed Loop Output Impedance vs Frequency 100 10 8 Supply Current (mA) 6 4 2 0 -2 10k 1M Frequency (Hz) 100M 1G
Supply Current vs Supply Voltage
10 Output Impedance ()
1
0.1
0.01
0.001 100
0
2
4
6 8 Supply Voltage (V)
10
12
2nd and 3rd Harmonic Distortion vs Frequency -10 -20 Harmonic Distortion (dBc) -30 -40 -50 -60 -70 -80 -90 1 10 Frequency (MHz) 100 200 3rd Order Distortion AV=+2 VOUT=2VP-P RL=100 30 25 Input Power Intercept (dBm) 20 15 10 5 0 -5 -10
Two-Tone 3rd Order Input Referred Intermodulation Intercept (IIP3)
2nd Order Distortion
AV =+2 RL=100 100 Frequency (MHz) 200
-15 10
Differential Gain/Phase vs DC Input Voltage at 3.58MHz 0.03 0.02 0.01 dG (%) or dP () 0 -0.01 -0.02 -0.03 -0.04 -0.05 -1 -0.5 0 DC Input Voltage 0.5 1 dG AV=2 RF=RG=250 RL=150 dP 0.03 0.02 0.01 dG (%) or dP () 0 -0.01 -0.02 -0.03
Differential Gain/Phase vs DC Input Voltage at 3.58MHz AV=1 RF=375 RL=500
dP
dG
-0.04 -1
-0.5
0 DC Input Voltage
0.5
1
6
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Output Voltage Swing vs Frequency THD<1% 10 RL=500 Output Voltage Swing (VPP) Output Voltage Swing (VPP) 8 RL=150 6 8 10
Output Voltage Swing vs Frequency THD<0.1% RL=500
RL=150 6
4
4
2 AV=2 0 1 10 Frequency (MHz) 100 200
2 AV=2 0 1 10 Frequency (MHz) 100
Small Signal Step Response VS=5V RL=150 AV=2
Large Signal Step Response VS=5V RL=150 AV=2
200mV/div
1V/div
10ns/div
10ns/div
Settling Time vs Settling Accuracy 25 AV=2 RL=150 VSTEP=5VP-P output 375 350 325 RoI (k) 15 300 275 250 5 225 0 0.01
Transimpedance (RoI) vs Temperature
20 Settling Time (ns)
10
0.1 Settling Accuracy (%)
1
200 -40
10
60 Die Temperature (C)
110
160
7
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Frequency Response (Gain) SO8 Package 6 AV =2, -1 Normalized Magnitude (dB) 2 0 90
Frequency Response (Phase) SO8 Package
-6
Phase ()
-2
AV=1
-90
-180
-10 RL=150 -14 1M 10M 100M Frequency (Hz) PSRR and CMRR vs Temperature 90 PSRR 70 ICMR/IPSR (A/V) 1G
-270 RL=150 -360 1M 10M 100M Frequency (Hz) ICMR and IPSR vs Temperature 2.5 2 1.5 1 0.5 0 -0.5 ICMRIPSR ICMR+ 1G
PSRR/CMRR (dB)
50 CMRR 30
10 -40
10
60 Die Temperature (C)
110
160
-1 -40
10
60 Die Temperature (C)
110
160
Offset Voltage vs Temperature 2 140 120 100 Input Current (A) 1 VOS (mV) 80 60 40 20
Input Current vs Temperature
IB+
0
IB0 -1 -40 10 60 Die Temperature (C) 110 160 -20 -40 10 60 Die Temperature (C) 110 160
8
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Positive Input Resistance vs Temperature 35 30 Supply Current (mA) 25 RIN (k) 20 15 10 5 0 -40 10
Supply Current vs Temperature
9
10
60 Die Temperature (C)
110
160
8 -40
10
60 Die Temperature (C)
110
160
Positive Output Swing vs Temperature for Various Loads 4.2 4.1 1k 4 VOUT (V) VOUT (V) 3.9 3.8 3.7 3.6 3.5 -40 150 -3.7 -3.8 -3.9 -4 -4.1 -3.5 -3.6
Negative Output Swing vs Temperature for Various Loads
150
1k
10
60 Die Temperature (C)
110
160
-4.2 -40
10
60 Die Temperature (C)
110
160
Output Current vs Temperature 140 Sink 4500 Slew Rate (V/S) 5000
Slew Rate vs Temperature AV=2 RF=RG=250 RL=150
135
IOUT (mA)
130
4000
125 Source 120
3500
115 -40
10
60 Die Temperature (C)
110
160
3000 -40
10
60 Die Temperature (C)
110
160
9
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Typical Performance Curves
Enable Response
Disable Response
500mV/div
500mV/div
5V/div 5V/div
20ns/div
400ns/div
Package Power Dissipation vs Ambient Temperature JEDEC JESD51-3 Low Effective Thermal Conductivity Test Board 0.7 0.6 625mW
8 SO
Power Dissipation (W)
0.5 0.4 391mW 0.3 0.2 0.1 0 0 25
16
C/ 0
25
Ambient Temperature (C)
W
SO 6C T2 3 /W
50
75 85 100
125
150
10
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Pin Descriptions
EL5196AC 8-Pin SO 1, 5 2 4 4 EL5196C EL5196AC 5-Pin SOT23 6-Pin SOT23 Pin Name NC INFunction Not connected Inverting input Equivalent Circuit
RG IN+ RF IN-
Circuit 1
3 4 6
3 2 1
3 2 1
IN+ V SOUT
Non-inverting input Negative supply Output
(See circuit 1)
OUT RF
Circuit 2
7 8
5
6 5
V S+ CE
Positive supply Chip enable
VS+
CE
VSCircuit 3
11
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Applications Information
Product Description
The EL5196C is a current-feedback operational amplifier that offers a wide -3dB bandwidth of 600MHz and a low supply current of 6mA per amplifier. The EL5196C 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 currentfeedback topology, the EL5196C does not have the normal gain-bandwidth product associated with voltagefeedback 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 EL5196C the ideal choice for many low-power/highbandwidth applications such as portable, handheld, or battery-powered equipment. For varying bandwidth needs, consider the EL5191C with 1GHz on a 9mA supply current or the EL5193C with 300MHz on a 4mA supply current. Versions include single, dual, and triple amp packages with 5-pin SOT23, 16-pin QSOP, and 8-pin or 16-pin SO outlines. 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 EL5196AC amplifier can be disabled placing its output in a high impedance state. When disabled, the amplifier supply current is reduced to < 150A. The EL5196AC 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 EL5196AC 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 EL5196AC 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 currentfeedback 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 openloop response. The use of large-value feedback and gain resistors exacerbates the problem by further lowering the pole frequency (increasing the possibility of oscillation.) The EL5196C has been optimized with a 375 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.
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 4.7 F tantalum capacitor in parallel with a 0.01 F capacitor has been shown to work well when placed at each supply pin. 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,
12
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Feedback Resistor Values
The EL5196C has been designed and specified at a gain of +2 with RF approximately 375. This value of feedback resistor gives 300MHz of -3dB bandwidth at A V=2 with 2dB of peaking. With AV=-2, an RF of 375 gives 275MHz of bandwidth with 1dB of peaking. Since the EL5196C 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 peaking can be easily modified by varying the value of the feedback resistor. Because the EL5196C is a current-feedback amplifier, its gain-bandwidth product is not a constant for different closed-loop gains. This feature actually allows the EL5196C 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 R F below the specified 375 and still retain stability, resulting in only a slight loss of bandwidth with increased closed-loop gain.
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 150, 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 EL5196C amplifier. Special circuitry has been incorporated in the EL5196C 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 150 at a gain of 2. Video performance has also been measured with a 500 load at a gain of +1. Under these conditions, the EL5196C 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 EL5196C is capable of providing a minimum of 120mA of output current. With a minimum of 120mA of output drive, the EL5196C is capable of driving 50 loads to both rails, making it an excellent choice for driving isolation transformers in telecommunications applications.
Supply Voltage Range and Single-Supply Operation
The EL5196C 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 EL5196C will operate on dual supplies ranging from 2.5V to 5V. With single-supply, the EL5196C 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 EL5196C has an input range which extends to within 2V of either supply. So, for example, on 5V supplies, the EL5196C has an input range which spans 3V. The output range of the EL5196C 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.
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 EL5196C 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 5 and 50) 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.
13
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
Current Limiting
The EL5196C 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 EL5196C, it is possible to exceed the 125C Absolute Maximum junction temperature under certain very high load current conditions. Generally speaking when RL falls below about 25, it is important to calculate the maximum junction temperature (T JMAX ) for the application to determine if power supply voltages, load conditions, or package type need to be modified for the EL5196C to remain in the safe operating area. These parameters are calculated as follows:
T J M AX = TM AX + ( J A x n x PD M AX )
where:
PDMAX for each amplifier can be calculated as follows:
V O UT M AX PD M A X = ( 2 x VS x I SM A X ) + ( VS - VOUT M A X ) x ---------------------------R
L
where:
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ecnatsiser daoL = LR )deriuqer( egatlov tuptuo mumixaM = XAMTUOV A1 fo tnerruc ylppus mumixaM = XAMSI eg atlov y lppuS = S V
14
EL5196C, EL5196AC
EL5196C, EL5196AC
Single 400MHz Fixed Gain Amplifier with Enable
General Disclaimer
Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.
WARNING - Life Support Policy
February 11, 2002
Elantec Semiconductor, Inc.
675 Trade Zone Blvd. Milpitas, CA 95035 Telephone: (408) 945-1323 (888) ELANTEC Fax: (408) 945-9305 European Office: +44-118-977-6020 Japan Technical Center: +81-45-682-5820
15
Elantec, Inc. products are not authorized for and should not be used within Life Support Systems without the specific written consent of Elantec, Inc. Life Support systems are equipment intended to support or sustain life and whose failure to perform when properly used in accordance with instructions provided can be reasonably expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. Products in Life Support Systems are requested to contact Elantec, Inc. factory headquarters to establish suitable terms & conditions for these applications. Elantec, Inc.'s warrant y is limited to replacement of defective components and does not cover injury to persons or property or other consequential damages.
Printed in U.S.A.

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