Features

1.1GHz small-signal bandwidth (A

= +2)

2500V/

s slew rate

0.03%, 0.02° D

, D

6ns settling time to 0.2%

3rd order intercept, 30dBm @ 70MHz

Dual ±5V or single 10V supply

High output current: 90mA

2.5dB noise figure

Applications

High performance RGB video

RF/IF amplifier

Instrumentation

Medical electronics

Active filters

High-speed A/D driver

High-speed D/A buffer

Typical Application

120MSPS High-Speed Flash ADC Driver

Pinout

DIP & SOIC

General Description

The CLC449 is an ultra-high-speed monolithic op amp, with a typ-
ical -3dB bandwidth of 1.1GHz at a gain of +2. This wideband op
amp supports rise and fall times less than 1ns, settling time of 6ns
(to 0.2%) and slew rate of 2500V/

s. The CLC449 achieves 2nd

harmonic distortion of -68dBc at 5MHz at a low supply current of
only 12mA. These performance advantages have been achieved
through improvements in National's proven current feedback
topology combined with a high-speed complementary bipolar
process.

The DC to 1.2GHz bandwidth of the CLC449 is suitable for many IF
and RF applications as a versatile op amp building block for replace-
ment of AC coupled discrete designs. Operational amplifier
functions such as active filters, gain blocks, differentiation, addition,
subtraction and other signal conditioning functions take full
advantage of the CLC449's unity-gain stable closed-loop
performance.

The CLC449 performance provides greater headroom for lower
frequency applications such as component video, high-resolution
workstation graphics, and LCD displays. The amplifier's 0.1dB
gain flatness to beyond 200MHz, plus 0.8ns 2V rise and fall times
are ideal for improved time domain performance.

addition, the 0.03%/0.02° differential gain/phase performance
allows system flexibility for handling standard NTSC and PAL
signals.

In applications using high-speed flash A/D and D/A converters, the
CLC449 provides the necessary wide bandwidth (1.1GHz), settling
(6ns to 0.2%) and low distortion into 50

loads to improve SFDR.

Frequency Response (A

= +2V/V)

CLC449
1.1GHz Ultra-Wideband Monolithic Op Amp

June 1999

CLC449

1.1GHz Ultra-Wideband Monolithic Op Amp

http://www.national.com

Printed in the U.S.A.

http://www.national.com

PARAMETERS

CONDITIONS TYP

MIN/MAX RATINGS

UNITS

NOTES

CLC449

+25°

0° to +70° -40° to +85°

FREQUENCY DOMAIN RESPONSE

-3dB bandwidth

small signal

<0.2V

1100

MHz

large signal

<2V

500

380

360

MHz

±0.1 dB bandwidth

<2V

200

MHz

gain flatness

peaking

DC to 200MHz

rolloff

DC to 200MHz

0.1

0.5

linear phase deviation

<200MHz

0.8

deg

differential gain

4.43MHz, R

=150

0.03

0.05

differential phase

4.43MHz, R

=150

0.02

0.05

deg

TIME DOMAIN RESPONSE

rise and fall time

2V step

0.8

1.1

settling time to 0.2%

2V step

settling time to 0.1%

2V step

overshoot

2V step

slew rate

4V step

2500

2000

DISTORTION AND NOISE RESPONSE

2nd harmonic distortion

, 5MHz

-63

dBc

, 20MHz

-52

-48

dBc

, 50MHz

-44

dBc

3rd harmonic distortion

, 5MHz

-84

dBc

, 20MHz

-73

-66

-64

dBc

, 50MHz

-62

dBc

3rd order intercept

70MHz

dBm

1dB gain compression @ 50MHz

dBm

equivalent input noise

non-inverting voltage

1MHz

2.2

2.9

nV/

inverting current

1MHz

20.0

pA/

non-inverting current

1MHz

5.0

pA/

STATIC DC PERFORMANCE

input offset voltage

average drift

V/°C

input bias current

non-inverting

average drift

nA/°C

input bias current

inverting

average drift

nA/°C

power supply rejection ratio

common-mode rejection ratio

supply current

13.5

MISCELLANEOUS PERFORMANCE

input resistance

non-inverting

400

200

150

input capacitance

non-inverting

1.3

output resistance

closed loop

0.1

0.15

0.25

output voltage range

3.3

3.1

=100

2.9

2.8

input voltage range

common-mode

2.4

2.2

2.1

1.9

output current

CLC449 Electrical Characteristics

= +2, R

= 250

= ±5V, R

= 100

; unless specified)

Absolute Maximum Ratings

±6V

out

is short circuit protected to ground

common-mode input voltage

±Vcc

maximum junction temperature

+150°C

operating temperature range

-40°C to +85°C

storage temperature range

-65°C to +150°C

lead temperature (soldering 10 sec)

+300°C

ESD (human body model)

500V

Notes

A) J-level: spec is 100% tested at +25°C.

Package Thermal Resistance

Package

Plastic (AJP)

90°C/W

105°C/W

Surface Mount (AJE)

110°C/W

130°C/W

Min/max ratings are based on product characterization and simulation. Individual parameters are tested as noted. Outgoing quality levels are
determined from tested parameters.

http://www.national.com

CLC449 Typical Performance Characteristics

= 25°C, V

= + 5V, R

= 250

, A

= +2, R

= 100

)

CLC449 OPERATION

Magnitude (1dB/div)

Input Offset Voltage, V

(mV)

Input Bias Current, I

, I

(

Settling Time (ns)

(ohms)

VSWR

Frequency (Hz)

1.9

1.8

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.0

0.9

Input VSWR

Non-Inverting

Inverting

100M

200M

300M

400M

500M

VSWR

Frequency (Hz)

2.8

2.6

2.4

2.2

2.0

1.8

1.6

1.4

1.2

1.0

0.8

Uncompensated

Compensated

100M

200M

300M

400M

500M

| (dB)

Frequency (Hz)

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

100M

200M

300M

400M

500M

Output VSWR

Reverse Isolation (S

)

Gain Compression

CLC449 Extended Application Information
The following design and application topics will supply
you with:

A comprehensive set of design parameters and
design parameter adjustment techniques.

A set of formulas that support design parameter
change prediction.

A series of common applications that the CLC449
supports.

A set of easy to use design guidelines for the
CLC449.

Additional design applications are possible with the
CLC449. If you have application questions, call 1-800-272-
9959 in the U.S. to contact a technical staff member.

DC Gain (Non-Inverting)
The non-inverting DC voltage gain for the configuration
shown in Figure 1 is:

Figure 1: Non-Inverting Gain

The normalized gain plots in the

Typical Performance

Characteristics section show different feedback resistors,
R

, for different gains. These values of R

are recom-

mended for obtaining the highest bandwidth with minimal
peaking. The resistor R

in Figure 1 provides DC bias for

the non-inverting input.

For A

5, calculate the recommended R

as follows:

340 - A

, where R

= 45

. For A

> 5, the

minimum recommended feedback resistor is R

= 100

Select R

to set the DC gain:

Accuracy of DC gain is usually limited by the tolerance of
the external resistors R

and R

DC Gain (Unity Gain Buffer)
Unity gain buffers are easily designed with a current-
feedback amplifier as long as the recommended feed-
back resistor R

= 402

is used and R

, i.e. open.

Parasitic capacitance at the inverting node may require a
slight increase of the feedback resistor R

to maintain a

flat frequency response.

DC Gain (Inverting)
The inverting DC voltage gain for the configuration shown
in Figure 2 is:

= +

CLC449

0.1

6.8

0.1

6.8

= -

http://www.national.com

Figure 2: Inverting Gain

The normalized gain plots in the

Typical Performance

Characteristics section show different feedback resistors,
R

, for different gains. These values of R

are recommended

for obtaining the highest bandwidth with minimal peaking.
The resistor R

in Figure 2 provides DC bias for the non-

inverting input.

For |Av|

4, calculate the recommended R

as follows:

295 - |A

, where R

= 45

. For |A

| > 4, the

minimum recommended feedback resistor is R

= 100

Select R

to set the DC gain:

At large gains, R

becomes small and will load the

previous stage.

This situation is resolved by driving

with a low impedance buffer like the CLC111,

or increasing R

and R

(see the

Bandwidth (Small

Signal) sub-section for the tradeoffs).

Accurate DC gain is usually limited by the tolerance of
the external resistors R

and R

Bandwidth (Small Signal)
The CLC449 current-feedback amplifier bandwidth is a
function of the feedback resistor (R

), not of the DC volt-

age gain (A

The bandwidth is approximately

proportional to 1/R

. As a rule, if R

doubles, the band-

width is cut in half. Other AC specifications will also be
degraded.

Decreasing R

from the recommended

value increases peaking and for very small values of
R

oscillation will occur.

With an inverting amplifier design, peaking is sometimes
observed. This is often the result of layout parasitics
caused by inadequate ground planes or long traces. If
this is observed, placing a 50 to 200

resistor between

the non-inverting pin and ground will usually reduce the
peaking.

Bandwidth (Minimum Slew Rate)
Slew rate influences the bandwidth for large signal
sinusoids. To determine an approximate value of slew
rate, necessary to support large sinusoids use the
following equation:

peak

is the peak output sinusoidal voltage, f is the

frequency of the sinusoid.
The slew rate of the CLC449 in inverting gains is always

higher than in non-inverting gains.

DC Design (Level Shifting)
Figure 3 shows a DC level shifting circuit for inverting
gain configurations. V

ref

produces a DC output level shift

which is independent of the DC output produced by V

Figure 3: Level Shifting Circuit

DC Design (Single Supply)
Figure 4 is a typical single-supply circuit. Resistors R

and R

form a voltage divider that sets the non-inverting

input DC voltage. This circuit has a DC gain of 1. The
coupling capacitor C

isolates the DC bias point from the

previous stage.

Both capacitors make a high pass

response; the high frequency gain is determined by R

and R

Figure 4: Single Supply Circuit

The complete gain equation for the circuit in Figure 4 is:

where s = j

= (R

|| R

)

, and

= R

DC Design (DC Offsets)
The DC offset model shown in Figure 5 is used to
calculate the output offset voltage. The equation for out-
put offset voltage is:

The current offset terms, I

and I

do not track each

other. The specifications are stated in terms of
magnitude only. Therefore, the terms V

, I

, and I

may have either positive or negative polarity. Matching
the equivalent resistance seen at both input pins does
not reduce the output offset voltage.

CLC449

0.1

6.8

0.1

6.8

| A |

-V

ref

eq2

CLC449

ref

eq1

CLC449

eq1

eq2

= -

(

)

(

)

1 s

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CLC449

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CLC449