Datasheet EL5191CW-T7, EL5191CW-T13, EL5191CS-T7, EL5191CS-T13, EL5191CS Datasheet (ELANT)

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Features

• 1GHz -3dB bandwidth

• 9mA supply current

• Single and dual sup p l y op er a tion,

from 5V to 10V supply span

• Available in 5-pin SOT23 package

• High speed, 600MHz product

available (EL519 2C, EL5292C,
and EL5392C)

• Lower power, 300MHz product
available (EL519 3C, EL5293C,
EL5393C)

Applications

• Video Amplifiers

• Cable Drivers

• RGB Amplifiers

• Test Equipment

• Instrumentation

• Current to Voltage Converters

Ordering Information

Part No Package

EL5191CW-T7 5-Pin SOT23 7” MDP0038 EL5191CW-T13 5-Pin SOT23 13” MDP0038 EL5191CS 8-Pin SO - MDP0027 EL5191CS-T7 8-Pin SO 7” MDP0027 EL5191CS-T13 8-Pin SO 13” MDP0027

Tape &

Reel Outline #

General Description

The EL5191C amplifier is of the current feedback variety and exhibits
a very high bandwidth of 1GHz. This makes this amplifier ideal for
today’s high speed video and monitor applications, as well as a num­ber of RF and IF frequen cy designs.

With a supply current of just 9mA and the ability to run from a single
supply voltage from 5V to 10V, these amplifiers offer very high per­formance for little power consumption.

For applications where board space is critical, the EL5191C is offered
in the 5-pin SOT23 package, as well as an industry standard 8-pin SO.
The EL5191C operates over the industrial temperature range of -40°C
to +85°C.

Pin Configurations

8-Pin SO

1

2

-

+

3

-

4

EL5191CS

8

NC*

7

VS+

OUT

6

NC

5

OUT

VS-

IN+

1

2

3

5-Pin SOT23

-+

EL5191CW

VS+

5

IN-

4

NC

IN-

IN+

V

S

* This pin must be left disconnected

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 . W e recommend checking the revision level befo re finalization of your design documentation.

© 2001 Elantec Semiconductor, Inc.

April 12, 2001

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Absolute Maximum Ratings (T

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 V
Maximum Continuous Output Current 50mA

+ and VS-11V

S

= 25°C)

A

Operating Junction Temperature 125°C
Power Dissipation See Curves
Pin Voltages V

- - 0.5V to VS+ +0.5V

S

Storage Temperature -65°C to +150°C
Operating Temperature -40°C to +85°C

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: T

= TC = TA.

J

Electrical Characteristics

VS+ = +5V, VS- = -5V, RF = 392Ω for AV = 1, RF = 250Ω for AV = 2, RL = 150Ω, TA = 25°C unless otherwise specified.

Parameter Description Conditions Min Typ Max Unit

AC Performance

BW -3dB Bandwidth A

BW1 0.1dB Bandwidth 30 MHz
SR Slew Rate V
ts 0.1% Settling Time V
e

n

i

- IN- input current noise 25 pA/√Hz

n

i

+ IN+ input current noise 55 pA/√Hz

n

dG Differential Gain Error
dP Differential Phase Error

Input Voltage Noise 3.8 nV/√Hz

[1]

[1]

DC Performance

V
T
R

OS
CVOS
OL

Offset Voltage -15 1 15 mV
Input Offset Voltage Temperature Coefficient Measured from T
Transimpedance 150 300 kΩ

Input Characteristics

CMIR Common Mode Input Range ±3 ±3.3 V CMRR Common Mode Rejection Ratio 42 50 dB

-ICMR - Input Current Common Mode Rejection -6 6 µA/V
+I

IN

-I

IN

R

IN

C

IN

+ Input Current -120 40 120 µA

- Input Current -40 5 40 µA
Input Resistance 27 kΩ
Input Capacitance 0.5 pF

Output Characteristics

V

I

OUT

O

Output Voltage Swing RL = 150Ω to GND ±3.4 ±3.7 V

Output Current RL = 10Ω to GND 95 120 mA

Supply

Is

ON

Supply Current No Load, V

PSRR Power Supply Rejection Ratio DC, V

-IPSR - Input Current Power Supply Rejection DC, V

1. Standard NTSC test, AC signal amplitude = 286mV

P-P

= +1 1000 MHz

V

A

= +2 600 MHz

V

= -2.5V to +2.5V, AV = [phone] V/µs

O

= -2.5V to +2.5V, AV = -1 7 ns

OUT

AV = +2 0.035 % AV = +2 0.04 °

to T

MIN

MAX

R

= 1KΩ to GND ±3.8 ±4.0 V

L

= 0V 8 9 10.5 mA

IN

= ±4.75V to ±5.25V 55 75 dB

S

= ±4.75V to ±5.25V -2 2 µA/V

S

5µV/°C

, f = 3.58MHz

2

Typical Performance Curves

EL5191C

EL5191C

1GHz Current Feedback Amplifier

Non-Inverting Frequency Response (Gain)
SOT23 Package

6

2

-2

-6

Normalized Magnitude (dB)

-10
RF=390Ω

RL=150Ω

-14

1M 10M 100M 1G

Frequency (Hz)

Inverting Frequency Response (Gain)
SOT23 Package

6

2

-2

-6

Normalized Magnitude (dB)

-10
RF=250Ω

RL=150Ω

-14

1M 10M 100M 1G

Frequency (Hz)

AV=1

AV=5

AV=10

AV=-2

AV=-5

AV=-1

AV=2

Non-Inverting Frequency Response (Phase)

90

0

-90

Phase (°)

-180

-270
RF=390Ω

RL=150Ω

-360

1M 10M 100M 1G

Inverting Frequency Response (Phase)

90

0

-90

Phase (°)

-180

-270
RF=250Ω

RL=150Ω

-360

1M 10M 100M 1G

AV=5

AV=10

Frequency (Hz)

AV=-2

AV=-5

Frequency (Hz)

AV=1

AV=2

AV=-1

Frequency Response for Various CIN-

10

6

2

-2

Normalized Magnitude (dB)

AV=2

-6
RF=250Ω

RL=150Ω

-10
1M 10M 1G

2pF added

1pF added

0pF added

100M

Frequency (Hz)

Frequency Response for Various R

6

2

-2

-6

Normalized Magnitude (dB)

-10
AV=2

RF=250Ω

-14

1M 10M 100M 1G

RL=100Ω

RL=500Ω

Frequency (Hz)

L

RL=150Ω

3

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Typical Performance Curves

Frequency Response for Various C

14

10

6

2

Normalized Magnitude (dB)

AV=2

-2
RF=250Ω

RL=150Ω

-6

1M 10M 100M 1G

Group Delay vs Frequency

3.5

3

2.5

2

1.5

Group Delay (ns)

1

0.5

0

1M 10M 1G

6pF added

4pF added

0pF added

Frequency (Hz)

AV=2

=250Ω

R

F

100M

Frequency (Hz)

L

AV=1

=390Ω

R

F

Frequency Response for Various R

6

2

-2

-6

Normalized Magnitude (dB)

AV=2

-10
RG=R

F

RL=150Ω

-14

1M 10M 100M 1G

Frequency Response for Various Common-mode
Input Voltages

6

2

-2

-6

Normalized Magnitude (dB)

AV=2

-10

RF=250Ω
RL=150Ω

-14

1M 10M 1G

150Ω

375Ω

500Ω

Frequency (Hz)

VCM=3V VCM=0V

VCM=-3V

100M

Frequency (Hz)

F

250Ω

Transimpedance (ROL) vs Frequency

10M

1M

)

Ω

100k

10k

Magnitude (

1k

100

1k

10k 100k 1M 10M 100M 1G

Phase

Gain

Frequency (Hz)

0

-90

-180

-270

-360

PSRR and CMRR vs Frequency

20

0

-20

Phase (°)

-40

PSRR/CMRR (dB)

-60

-80

10k

PSRR-

100k 1M 10M 1G100M

Frequency (Hz)

PSRR+

CMRR

4

Typical Performance Curves

EL5191C

EL5191C

1GHz Current Feedback Amplifier

-3dB Bandwidth vs Supply Voltage for Non­inverting Gains

1200

RF=390Ω
RL=150Ω

1000

800

600

400

-3dB Bandwidth (MHz)
200

0

56 10

Peaking vs Supply Voltage for Non-inverting Gains

4

3.5
3

2.5
2

Peaking (dB)

1.5
1

0.5
0

56 10879

AV=1

AV=2

AV=5

8

79

Total Supply Voltage (V)

AV=1

AV=2

AV=10

Total Supply Voltage (V)

AV=10

RF=390Ω

=150Ω

R

L

-3dB Bandwidth vs Supply Voltage for Inverting
Gains

600

500

400

300

200

-3dB Bandwidth (MHz)
100

RF=250Ω
RL=150Ω

0

56 10

Peaking vs Supply Voltage for Inverting Gains

4

3

2

Peaking (dB)

1

RF=250Ω

=150Ω

R

L

0

56 10879

AV=-1

AV=-5

Total Supply Voltage (V)

Total Supply Voltage (V)

AV=-2

79

8

AV=-1

AV=-2

AV=-5

Non-inverting Frequency Response (Gain)
SO8 Package

6

2

-2

-6

Normalized Magnitude (dB)

-10
RF=392Ω

RL=150Ω

-14

1M 10M 1G

AV=1 AV=2

AV=5

AV=10

100M 1.6G

Frequency (Hz)

Non-inverting Frequency Response (Phase)
SO8 Package

90

0

-90

Phase (°)

-180

-270
RF=392Ω

RL=150Ω

-360

1M 10M 1G

AV=1 AV=2

AV=5

AV=10

100M

Frequency (Hz)

5

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Typical Performance Curves

Inverting Frequency Response (Gain)
SO8 Package

6

2

-2

-6

Normalized Magnitude (dB)

-10
RF=250Ω

RL=150Ω

-14

1M 10M

-3dB Bandwidth vs Temperature for Non-inverting
Gains

2000

1500

1000

-3dB Bandwidth (MHz)

500

0

-40 10 60 160

AV=2

Ambient Temperature (°C)

AV=-1 AV=-2

AV=-5

100M 1G

Frequency (Hz)

AV=1

AV=5 AV=10

RF=250Ω
RL=150Ω

110

Inverting Frequency Response (Phase)
SO8 Package

90

0

-90

Phase (°)

-180

-270
RF=250Ω

RL=150Ω

-360

1M 10M

-3dB Bandwidth vs Temperature for Inverting
Gains

700

600

500

400

300

200

-3dB Bandwidth (MHz)
RF=250Ω

100

=150Ω

R

L

0

-40 10 60 160

AV=-1 AV=-2

AV=-5

100M 1G

Frequency (Hz)

AV=-1

AV=-2

AV=-5

Ambient Temperature (°C)

110

Peaking vs Temperature

3

2.5

2

1.5

Peaking (dB)

1

0.5

0

-40 10 60 160

AV=1

AV=-1

AV=-2

Ambient Temperature (°C)

RL=150Ω

110

Voltage and Current Noise vs Frequency

1000

Hz)

Hz)

√

100

√

10

Voltage Noise (nV/

, Current Noise (pA/

1

100

in+

in-

e

n

1000 10k 100k 10M1M

Frequency ()

6

Typical Performance Curves

EL5191C

EL5191C

1GHz Current Feedback Amplifier

Closed Loop Output Impedance vs Frequency

100

10

)

Ω

1

0.1

Output Impedance (

0.01

0.001
100

2nd and 3rd Harmonic Distortion vs Frequency

-10

-20

-30

-40

-50

-60

-70

Harmonic Distortion (dBc )

-80

-90

-100
1

10k 100M1M

1k 10M 1G100k

AV=+2
V

=2V

OUT

P-P

RL=100Ω

2nd Order
Distortion

Frequency (Hz)

3rd Order
Distortion

10 100 200

Frequency (MHz)

Supply Current vs Supply Voltage

10

8

6

4

Supply Current (mA)

2

0

0

Two-tone 3rd Order
Input Referred Intermodulation Intercept (IIP3)

30
25
20
15
10

5
0

Input Power Intercept (dBm)

-5
AV=+2

=100Ω

R

L

-10

-15
10

Supply Voltage (V)

Frequency (MHz)

12210864

100 200

Differential Gain/Phase vs DC Input
Voltage at 3.58MHz

0.03
AV=2

RF=RG=250Ω
RL=150Ω

0.01

-0.01

dG (%) or dP (°)

-0.03

-0.05

-1 -0.5 0 0.5 1
DC Input Voltage

Differential Gain/Phase vs DC Input
Voltage at 3.58MHz

0.03

dP

dG

AV=1

0.02

RF=375Ω
RL=500Ω

0.01

0

-0.01

dG (%) or dP (°)

-0.02

-0.03

-0.04

-1 -0.5 0 0.5 1
DC Input Voltage

dP

dG

7

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Typical Performance Curves

)

PP

Output Voltage Swing (V

200mV/div

Output Voltage Swing vs Frequency
THD<1%

10

RL=500Ω

8

6

4

2

0

RL=150Ω

AV=2 AV=2

1

Small Signal Step Response Large Signal Step Response

10 100 200

Frequency (MHz)

VS=±5V

=150Ω

R

L

AV=2
R

=250Ω

F=RG

Output Voltage Swing vs Frequency
THD<0.1%

10

RL=500Ω

8

)

PP

Output Voltage Swing (V

1V/div

RL=150Ω

6

4

2

0

1

Frequency (MHz)

10 100

VS=±5V

=150Ω

R

L

AV=2
R

=250Ω

F=RG

10ns/div

Settling Time vs Settling Accuracy

25

20

15

10

Settling Time (ns)

5

0

0.01 0.1 1
Settling Accuracy (%)

AV=2
RF=RG=250Ω
RL=150Ω
V

STEP

=5V

P-P

output

10ns/div

Transimpedance (RoI) vs Temperature

375

350

325

)

300

Ω

275

RoI (k

250

225

200

-40 10 60 110 160
Die Temperature (°C)

8

Typical Performance Curves

EL5191C

EL5191C

1GHz Current Feedback Amplifier

PSRR and CMRR vs Temperature

90

70

50

PSRR/CMRR (dB)

30

10

-40 10 60 110 160
Die Temperature (°C)

Offset Voltage vs Temperature

2

1

(mV)

OS

V

0

-1

-40 10 60 110 160
Die Temperature (°C)

PSRR

CMRR

ICMR and IPSR vs Temperature

2.5

2

1.5

1

0.5

ICMR/IPSR (µA/V)

0

-0.5

-1

-40 10 60 110 160

Input Current vs Temperature

140
120
100

80
60
40

Input Current (µA)

20

0

-20

-40 10 60 110 160

ICMR+

IPSR

ICMR-

Die Temperature (°C)

IB+

IB-

Temperature (°C)

Positive Input Resistance vs Temperature

35

30

25

)

20

Ω

(k

IN

15

R

10

5

0

-40 10 60 110 160

Temperature (°C)

Supply Current vs Temperature

10

9

Supply Current (mA)

8

-40 10 60 110 160
Temperature (°C)

9

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Typical Performance Curves

Positive Output Swin g v s T emper atu re for Var iou s
Loads

4.2

4.1

4

3.9

(V)

OUT

3.8

V

3.7

3.6

3.5

-40 10 60 110 160

Output Current vs Temperature

140

135

130

(mA)

OUT

I

125

120

115

-40 10 60 110 160

1kΩ

150Ω

Temperature (°C)

Sink

Source

Die Temperature (°C)

Negative Output Swing vs T emperature for Vari ous
Loads

-3.5

-3.6

-3.7

-3.8

(V)

OUT

-3.9

V

-4

-4.1

-4.2

-40 10 60 110 160

Slew Rate vs Temperature

5000

4500

4000

Slew Rate (V/µS)

3500

3000

-40 10 60 110 160

150Ω

1kΩ

Temperature (°C)

Die Temperature (°C)

AV=2
RF=RG=250Ω
RL=150Ω

Maximum Power Dissipation vs Ambient
Temperature

1.4

1.2

1

0.8

0.6

0.4

Power Dissipation (W)

0.2

0

-50 0 50 100

SO8

SOT23

Ambient Temperature (°C)

Package Power Dissipation vs Ambient Temp.

JEDEC JESD51-3 Low Effectiv e Therm al Conductivity Test Board

0.7

T

=150°C

JMAX

625mW

0.6

0.5
391mW

0.4

0.3

0.2

Power Dissipation (W)

0.1

0

0 50 100 150

SO

160°

8

C/W

S

O

T

2

3

5

2

L

5

6

°

C

/

W

25 75 125

Ambient Temperature (°C)

10

Pin Descriptions

EL5191C

8-Pin SO

1,5 NC Not connected

EL5191C

5-Pin SOT23

2 4 IN- Inverting input

Pin Name Function Equivalent Circuit

EL5191C

EL5191C

1GHz Current Feedback Amplifier

VS+

IN-IN+

3 3 IN+ Non-inverting input (See circuit 1)
42V
6 1 OUT Output

75V
8 NC Not connected (leave this pin disconnected)

- Negative supply

S

+ Positive supply

S

Circuit1

VS-

VS+

OUT

VS-

Circuit 2

11

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Applications Information

Product Description

The EL5191C is a current-feedback operational ampli­fier that offers a wide -3 dB bandwidth of 1 GHz and a
low supply current of 9mA per amplifier. The EL5191C
works with supply voltages ranging from a single 5V to
10V and they are also capabl e of swi ngi ng t o wi thin 1 V
of either supply on the output. Because of their current­feedback topolo gy , t he EL 5 19 1C do es not hav e t he nor ­mal gain-bandwidth product associated with voltage­feedback operational amp lifiers. Instead, its -3dB band­width to remain relatively c onstant as c losed-loop gain is
increased. This combination of high bandwidth and low
power, together with aggressive pricing make the
EL5191C the ideal choice for many low-power/high­bandwidth applications such as portable, handheld, or
battery-powered equipment.

For varying bandwidth needs, con sider the EL5192C
with 600MHz on a 6mA supply current or the EL5193C
with 300MHz on a 4mA supply current. Versions
include single, dua l, a nd tri ple amp pa cka ges w ith 5-p in
SOT23, 16-pin QSOP, and 8-pin or 16-pin SO outlines.

Power Supply Bypassing and Printed Circuit
Board Layout

As with any hig h fr e que ncy d evi ce , good pr in te d c irc uit
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 pi ns must be well
bypassed to reduce the risk of os cilla tion. The co mbin a­tion of a 4.7µF tantalum capacitor in parallel with a

0.01µ F capacitor has been shown to work well when
placed at each supply pin.

For good AC performance, parasitic capacitan ce should
be kept to a minimum, especially at the inverting input.
(See the Capacitance at the Inverting Input section) Even
when ground plane construction i s 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 ind uctance and c apaci­tance which will result in additional peaking and
overshoot.

Capacitance at the Inverting Input

Any manufacturer’s high-speed voltage- or current­feedback amplifier can b e affected by stra y capacitan ce
at the inverting input. For inverting gains, this parasitic
capacitance has little e ffect because t he inverting i nput is
a virtual ground. But fo r no n- inv e rtin g g ai ns, this c apa c ­itance (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 ze ro 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 EL5191C has been optimized with a 250Ω 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 recommende d aroun d the inv erting in put pi n
of the amplifier.

Feedback Resistor Values

The EL5191C has been des ig ned and spec ifi ed at a gai n
of +2 with R
back resistor gives 600MHz of -3dB bandwidth at A
with about 2dB of peaking. With A
gives 450MHz of bandwidth with 0.6dB of peaking.
Since the EL5191C is a cu rrent-fee dback amp lifier, it i s
also possible to change the value of R
width. As seen in the curve of Frequency Response for
Various RF and RG, bandwidth and peaki ng can be eas­ily modified by varying the val ue of the feedback
resistor.

Because the EL5191C is a current-feedback amplifier,
its gain-bandwidth product is not a constant for different
closed-loop gains. This feature actually allows the
EL5191C to maintain about the same -3dB bandwidth.
As gain is increased, bandwidth decreases slightly while

approximately 250Ω. This value of feed-

F

=-2, that same R

V

to get more band-

F

=2

V

F

12

EL5191C

1GHz Current Feedback Amplifier

EL5191C

stability increases. Since the loop stability is improving
with higher closed-loop gains, it becomes possible to
reduce the value of R
still retain stability, resulting in only a slight loss of
bandwidth with inc reased closed-loop ga in.

below the specified 250Ω and

F

Supply Voltage Range and Single-Supply
Operation

The EL5191C 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 EL5191C
will operate on dual supplies ranging from ±2.5V to
±5V. With single-supply, the EL5191C 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
EL5191C has an input ran ge which e xtends to with in 2V
of either supply. So, for example, on ±5V supplies, the
EL5191C has an input ran ge wh ic h span s ±3V. The out­put range of the EL5191C 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-sup ply output range is larger because of the
increased negative swing due to the external pull-down
resistor t o gr o u n d.

Video Performance

For good video performance, an amplifier is required to
maintain the same output impedance and the same fre­quency response as DC level s are changed at the output .
This is especially difficult when driving a standard vid eo
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 9mA supply current of each EL5191C
amplifier. Special circuitry has been incorporated in the
EL5191C to reduce the variation of output impedance
with current output. This results in dG and dP specifica­tions of 0.035% and 0.04°, while driving 150 Ω at a gain
of 2.

Video performance has also been measured with a 500Ω
load at a gain of +1. Under these conditions, the
EL5191C has dG and dP specifications of 0.02% and

0.02°, respectively.

Output Drive Capability

In spite of its low 9mA of supply current, the EL5191C
is capable of providin g a minimu m of ±95mA of ou tput
current. With a minimum of ±95mA of output drive, the
EL5191C is 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 perfo rmance.
For those applications, the back-term ina tion series re sis­tor will decouple the EL5191C from the c ab le an d allo w
extensive capacitive drive. However, other applications
may have high capaci tiv e loa ds wit hout a b ack -te rmina­tion resistor. In these applications, a small series resist or
(usually between 5Ω and 50Ω) can be placed in series
with the output to eliminate most peaking. The gain
resistor (R
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 (R
the peaking.

) can then be c hosen to make up for any ga in

G

) to reduce

F

Current Limiting

The EL5191C has no internal current-limiting circuitry.
If the output is shorted, it is possible to ex ceed the Abso ­lute Maximum Rating for o utput current or power
dissipation, potentially resultin g in the d estr uctio n o f th e
device.

Power Dissipation

With the high output drive ca p ability of the EL5191C, it
is possible to exceed the 125°C Absolute Maximum
junction temperature under certain very high load cur­rent conditions. Generally speaking when R
about 25Ω, it is important to calculate the maximum
junction temperature (T
determine if power supply voltages, load conditions, or
package type need t o be modified for the EL 5191C to

) for the application to

JMAX

falls below

L

13

EL5191C

1GHz Current Feedback Amplifier

EL5191C

remain in the safe operating area. These parameters are
calculated as follows:

T

JMAXTMAXθJA

nPD

××()+=

where:

 0D[LPXP$PELHQW7HPSHUDWXUH

7

0$;

θ

 7KHUPDO5HVLVWDQFHRIWKH3DFNDJH

-$

Q 1XPEHURI$PSOLILHUVLQWKH3DFNDJH

 0D[LPXP3RZHU'LVVLSDWLRQRI(DFK

3'

0$;

$PSOLILHULQWKH3DFNDJH

PD

for each amplifier can be calculated as follows:

MAX

PD

MAX

2( VSI

SMAX

) VS( V

OUTMAX

where:

96 6XSSO\9ROWDJH

 0D[LPXP6XSSO\&XUUHQWRI$

,

60$;

9

2870$;

5

/

 0D[LPXP2XWSXW9ROWDJH5HTXLUHG

 /RDG5HVLVWDQFH

MAX

V

----------------------------

)

×–+××=

OUTMAX

R

L

14

Typical Application Circuits

Inverting 200mA Output Current Distribution Amplifier

EL5191C

EL5191C

1GHz Current Feedback Amplifier

+5V

IN+

IN-

-5V

+5V

IN+

IN-

-5V

250Ω 250Ω

V

IN

Fast-Settling Precision Amplifier

250Ω 250Ω

250Ω

0.1µF

V

+

S

OUT

VS-

0.1µF

250Ω 5Ω

0.1µF

V

+

S

OUT

-

V

S

0.1µF

VS+

VS-

0.1µF

OUT

0.1µF

+5V

IN+

IN-

-5V

V

OUT

5Ω

VS+

VS-

0.1µF

0.1µF

OUT

V

OUT

250Ω

V

IN

+5V

IN+

IN-

-5V

15

EL5191C

1GHz Current Feedback Amplifier

EL5191C

Typical Application Circuits

Differential Line Driver/Receiver

V

IN

+5V

IN+

IN-

-5V
250Ω 120Ω

+5V

IN+

IN-

-5V

250Ω 250Ω

VS+

VS-

VS+

VS-

0.1µF

0.1µF

0.1µF

0.1µF

OUT

OUT

120Ω

ReceiverTransmitter

250Ω

VS+

VS-

VS+

VS-

0.1µF

0.1µF

0.1µF

0.1µF

OUT

OUT

V

OUT

+5V

IN+

IN-

V

+

OUT

V

-

OUT

0.1µF

1kΩ

240Ω

0.1µF

1kΩ

-5V

250Ω

+5V

IN+

IN-

-5V

250Ω 250Ω

16

EL5191C

1GHz Current Feedback Amplifier

EL5191C

General Disclaimer

Specifications contained in this data sheet are in effect as of the publicat ion date shown. Elantec, Inc. re serves the r ight to make changes in th e cir­cuitry or specifications cont ained herein at a ny time without notice. Elantec , Inc. assumes no res ponsibili ty for t he us e of an y circuits descr ibed
herein and makes no representations that they are free from patent infringement.

WARNING - Life Support Policy

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 intend ed to sup-

Elantec Semiconductor, Inc.

675 Trade Zone Blvd.
Milpitas, CA 95035
Telephone: [phone]

Fax: [phone]
European Office: [phone]
Japan Technical Center: [phone]

April 12, 2001

(888) ELANTEC

port 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 applicatio n of Elantec, Inc. P roducts in Li fe Support
Systems are requested to contact Elantec, Inc. factory headquarters
to establish suitable terms & conditions for these applications. Elan­tec, Inc. ’s warranty is limited to replacement of defective
components and does not cov er injury to persons or prop erty or
other consequential damages.

17

Printed in U.S.A.