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.

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Features

· Voltage noise of only 0.83nV/

· Current noise of only 2.4pA/

· Low offset voltage

200µV

· 180MHz -3dB BW for A

=10

· Low supply current - 10mA
· SOT23 package available
· ±2.5V to ±15V operation

Applications

· Ultrasound input amplifiers
· Wideband instrumentation
· Communication equipment
· AGC & PLL active filters
· Wideband sensors

Ordering Information

Part No

Package

Tape & Reel

Outline #

EL2125CW

5-Pin SOT23

MDP0038

EL2125CS

8-Pin SO

MDP0027

EL2125CN

8-Pin PDIP

MDP0031

General Description

The EL2125C is an ultra-low noise, wideband amplifier that runs on
half the supply current of competitive parts. It is intended for use in
systems such as ultrasound imaging where a very small signal needs to
be amplified by a large amount without adding significant noise. Its
low power dissipation enables it to be packaged in the tiny SOT23
package, which further helps systems where many input channels cre-
ate both space and power dissipation problems.

The EL2125C is stable for gains of 10 and greater and uses traditional
voltage feedback. This allows the use of reactive elements in the feed-
back loop, a common requirement for many filter topologies. It
operates from ±2.5V to ±15V supplies and is available in a 5-pin
SOT23 package and 8-pin SO and 8-pin PDIP packages.

The EL2125C is fabricated in Elantec's proprietary complementary
bipolar process, and is specified for operation from -45°C to +85°C.

Connection Diagrams

EL2125CS

(8-Pin SO and 8-Pin PDIP)

EL2125CW

(5-Pin SOT23)

VS+

IN-

IN+

VS-

OUT

IN-

IN+

VS-

VS+

OUT

EL2125C - Preliminary

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EL2125C - Preliminary

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Absolute Maximum Ratings

= 25°C)

+ to V

33V

Continuous Output Current

40mA

Any Input

- - 0.3V to V

+ + 0.3V

Power Dissipation

See Curves

Operating Temperature

-45°C to +85°C

Storage Temperature

-60°C to +150°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

= T

Electrical Characteristics

= ±5V, T

= 25°C, R

= 180

, R

= 20

, R

= 500

unless otherwise specified.

Parameter

Description

Conditions

Min

Typ

Max

Unit

DC Performance
V

Input Offset Voltage (SO8 & PDIP8)

-0.2

Input Offset Voltage (SOT23-5)

CVOS

Offset Voltage Temperature Coefficient

TBD

µV/°C

Input Bias Current

-30

-21

µA

Input Bias Current Offset

0.2

µA

CIB

Input Bias Current Temperature Coefficient

TBD

nA/°C

Input Capacitance

2.2

VOL

Open Loop Gain

PSRR

Power Supply Rejection Ratio

[1]

CMRR

Common Mode Rejection Ratio

[2]

100

CMIR

Common Mode Input Range

OUT

Output Voltage Swing

No load, R

= 1k

3.5

3.8

OUTL

Output Voltage Swing

= 100

2.8

3.1

OUT

Output Short Circuit Current

[3]

100

Supply Current

10.1

AC Performance - R

= 20

, C

= 5pF

-3dB Bandwidth

175

MHz

BW ±0.1dB

±0.1dB Bandwidth

MHz

BW ±1dB

±1dB Bandwidth

150

MHz

Peaking

0.4

Slew Rate

OUT

= 2V

, measured at 20% to 80%

TBD

190

V/µs

Overshoot, 4Vpk-pk Output Square Wave

Positive

0.6

Negative

2.7

Settling Time to 0.1% of ±1V Pulse

TBD

Voltage Noise Spectral Density

0.83

nV/

Current Noise Spectral Density

2.4

pA/

HD2

2nd Harmonic Distortion

[4]

TBD

dBc

HD3

3rd Harmonic Distortion

[4]

TBD

dBc

THD

Total Harmonic Distortion

[5]

TBD

dBc

IMD

Intermodulation Distortion

[6]

TBD

1. Measured by moving the supplies from ±4V to ±6V
2. Measured by moving the inputs from +3.5V to -4.4V
3. Pulse test only
4. Frequency = 10MHz, V

OUT

= 1Vpk-pk, into 100

and 5pF load

5. Frequency = 20MHz, V

OUT

= -20dBm (0.0274V

RMS

) into 500

and 15pF load

6. Two-tone IMD, frequencies = 5MHz and 6MHz at -20dBm output level, R

LOAD

= 500

and 15pF

EL2125C - Preliminary

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Electrical Characteristics

= ±15V, T

= 25°C, R

= 180

, R

= 20

, R

= 500

unless otherwise specified.

Parameter

Description

Conditions

Min

Typ

Max

Unit

DC Performance
V

Input Offset Voltage (SO8 & PDIP8)

-0.2

Input Offset Voltage (SOT23-5)

CVOS

Offset Voltage Temperature Coefficient

TBD

µV/°C

Input Bias Current

-30

-21

µA

Input Bias Current Offset

0.16

µA

CIB

Input Bias Current Temperature Coefficient

TBD

nA/°C

Input Capacitance

2.2

VOL

Open Loop Gain

PSRR

Power Supply Rejection Ratio

[1]

CMRR

Common Mode Rejection Ratio

[2]

100

CMIR

Common Mode Input Range

TBD

OUT

Output Voltage Swing

No load, R

= 1k

13.5

OUTL

Output Voltage Swing

Positive, R

= 180

, R

= 500

12.1

Negative

-11.3

OUT

Output Short Circuit Current

[3]

100

150

Supply Current

10.8

AC Performance - R

= 20

, C

= 5pF

-3dB Bandwidth

220

MHz

BW ±0.1dB

±0.1dB Bandwidth

MHz

BW ±1dB

±1dB Bandwidth

MHz

Peaking

2.5

Slew Rate

OUT

= 2V

, measured at 20% to 80%

TBD

225

V/µs

Overshoot, 4Vpk-pk Output Square Wave

0.6

Settling Time to 0.1% of ±1V Pulse

TBD

Voltage Noise Spectral Density

0.95

nV/

Current Noise Spectral Density

2.1

pA/

HD2

2nd Harmonic Distortion

[4]

TBD

dBc

HD3

3rd Harmonic Distortion

[4]

TBD

dBc

THD

Total Harmonic Distortion

[5]

TBD

dBc

IMD

Intermodulation Distortion

[6]

TBD

1. Measured by moving the supplies from ±13.5V to ±16.5V
2. Measured by moving the inputs from +13.5V to -14.4V
3. Pulse test only
4. Frequency = 10MHz, V

OUT

= 1Vpk-pk, into 100

and 5pF load

5. Frequency = 20MHz, V

OUT

= -20dBm (0.0274V

RMS

) into 500

and 15pF load

6. Two-tone IMD, frequencies = 5MHz and 6MHz at -20dBm output level, R

LOAD

= 500

and 15pF

EL2125C - Preliminary

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Typical Performance Curves

Non-Inverting Frequency Response for Various R

-5

10M

100M

Frequency (Hz)

N
o
r
m

a
l
i
z
e
d

G

a
i
n

(
d
B
)

Inverting Frequency Response for Various R

-2

-6

-10

-14

10M

100M

Frequency (Hz)

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Inverting Frequency Response for Various R

-2

-6

-10

-14

10M

100M

Frequency (Hz)

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Non-Inverting Frequency Response for Various R

-5

10M

100M

Frequency (Hz)

N
o
r
m

a
l
i
z
e
d

G

a
i
n

(
d
B
)

=1k

=499

=180

=100

=1k

=180

=700

=100

=499

=±5V

=-10

=5pF

=1k

=350

=200

=97.6

=499

=±15V

=-10

=5pF

=1k

=350

=200

=499

=97.6

=±5V

=10

=500

=5pF

=±15V

=10

=500

=5pF

-5

10M

100M

Frequency (Hz)

N
o
r
m

a
l
i
z
e
d

G

a
i
n

(
d
B
)

Non-Inverting Frequency Response vs Gain

=±5V

=500

=5pF

=20

-5

N
o
r
m

a
l
i
z
e
d

G

a
i
n

(
d
B
)

Non-Inverting Frequency Response for Various Gain

=10

=20

=50

=±15V

=500

=5pF

=700

10M

100M

Frequency (Hz)

=10

=20

=50

EL2125C - Preliminary

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Typical Performance Curves

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Inverting Frequency Response vs Gain

-2

-6

-10

-14

N
o
r
m

a
l
i
z
e
d

G

a
i
n

(
d
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)

Inverting Frequency Response vs Gain

10M

100M

Frequency (Hz)

-14

=-10

=350k

=-50

=1.75k

=-20

=700k

=±5V

=500

=5pF

10M

100M

Frequency (Hz)

=-50

=-20

=-10

=±15V

=500

=5pF

=50

-5

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Non-Inverting Frequency Response for Various Output

Signal Levels

-14

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Inverting Frequency Response for Various Output Signal

Levels

10M

100M

Frequency (Hz)

=±5V

=10

=180

= 500

=5pF

30mV

500mV

10M

100M

Frequency (Hz)

=±5V

=-10

=350

= 500

=5pF

2.5V

500mV

3.3V

250mV

3mV

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Non-Inverting Frequency Response for Various C

-1

-3

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Non-Inverting Frequency Response for Various C

-5

10M

100M

Frequency (Hz)

=±5V

=10

=180

=500

=28.5pF

=16pF

=5pF

=1pF

-5

10M

100M

Frequency (Hz)

=±5V

=10

=700

=500

=17pF

=11pF

=1.2pF

=5pF

EL2125C - Preliminary

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o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Inverting Frequency Response for Various C

o
r
m

a
l
i
z
e
d

G
a
i
n

(
d
B
)

Inverting Frequency Response for Various C

-2

-6

-10

10M

100M

Frequency (Hz)

-14

=29.4pF

=16.4pF

=11.4pF

=5.1pF

=1.2pF

=±5V

=10

=350

=500

-14

10M

100M

Frequency (Hz)

=29.4pF

=16.4pF

=11.4pF

=5.1pF

=1.2pF

=±15V

=10

=500

O
p
e
n

L
o
o
p

G
a
i
n

(
d
B
)

10k

Open Loop Gain and Phase

10M

100

100k

100M

Frequency (Hz)

P
h
a
s
e

(
°
)

-250

-50

-150

150

250

Supply Voltage (±V)

S
u
p
p
l
y

C
u
r
r
e
n
t

(
m

A
)

Supply Current vs Supply Voltage

4.8

2.4

9.6

7.2

Peaking vs Supply Voltage

2.5

1.5

0.5

(±V)

P
e
a
k
i
n
g

(
d
B
)

=10

=-10

=50

=-50

=20

=-20

3dB Bandwidth vs Supply Voltage

250

200

150

100

(±V)

B
a
n
d
w

i
d
t
h

(
M

H
z
)

=10

=-10

=50

=-50

=20

=-20

400M

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Typical Performance Curves

10ns/div

2
0
m

V
/
d
i
v

Small Signal Step Response

=±5V

=500

=180

=10

=5pF

10ns/div

2
0
m

V
/
d
i
v

=±15V

=500

=180

=10

=5pF

Time (20ns/div)

O
u
t
p
u
t

V
o
l
t
a
g
e

(
0
.
5
V
/
d
i
v
)

Large-Signal Step Response

=±5V

=500

=180

=10

=5pF

Time (20ns/div)

O
u
t
p
u
t

V
o
l
t
a
g
e

(
0
.
5
V
/
d
i
v
)

Large-Signal Step Response

=±15V

=500

=180

=10

=5pF

1MHz Harmonic Distortion vs Output Swing

-40

-50

-60

-70

-90

-100

-110

OUT

)

i
s
t
o
r
t
i
o
n

(
d
B
c
)

1MHz Harmonic Distortion vs Output Swing

-30

-40

-60

-80

-90

-100

-110

OUT

)

i
s
t
o
r
t
i
o
n

(
d
B
c
)

-80

=±5V

=180

=10

=500

2nd H

3rd H

=±15V

=180

=10

=500

-50

-70

2nd H

3rd H

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Typical Performance Curves

Voltage and Current Noise vs Frequency

100

0.1

100

10k

100k

Frequency (Hz)

V
o
l
t
a
g
e

N

o
i
s
e

(
n
V
/

z
)
,

C
u
r
r
e
n
t

N
o
i
s
e

(
p
A
/

H
z
)

, V

=±15V

, V

=±5V

, V

=±15V

, V

=±5V

Settling Time vs Accuracy

0.1

Accuracy (%)

S
e
t
t
l
i
n
g

T
i
m

e

(
n
s
)

=±15V

=5V

=±5V

=5V

=±15V

=2V

=±5V

=2V

Total Harmonic Distortion vs Frequency

-30

-60

-80

-90

10k

100M

Frequency (Hz)

T
H

D

(
d
B
c
)

=±5V

=2V

=10

=180

=500

100k

10M

-40

-50

-70

-6

400

Frequency (MHz)

G
r
o
u
p

D
e
l
a
y

(
n
s
)

Group Delay

-2

100

=20

=10

=±15V

-110

-10

100M

Frequency (Hz)

C
M

(
d
B
)

CMRR

-70

-30

-50

-99

100

10M

10k

100k

P
S
R
R

(
d
B
)

10K

PSRR

10M

110

100K

100M

Frequency (Hz)

PSRR-

PSRR+

600M

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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 cir-
cuitry 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

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 sup-
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 con-
templating 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. Elan-
tec, Inc.'s warranty is limited to replacement of defective
components and does not cover injury to persons or property or
other consequential damages.

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Printed in U.S.A.

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

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: EL2125CW

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: EL2125CW