Analog Devices AD844 Datasheet

60 MHz, 2000 V/ms

a

FEATURES
Wide Bandwidth: 60 MHz at Gain of –1

Wide Bandwidth: 33 MHz at Gain of –10

Very High Output Slew Rate: Up to 2000 V/ms
20 MHz Full Power Bandwidth, 20 V pk-pk, R
Fast Settling: 100 ns to 0.1% (10 V Step)
Differential Gain Error: 0.03% at 4.4 MHz
Differential Phase Error: 0.158 at 4.4 MHz
High Output Drive: 650 mA into 50 Ω Load
Low Offset Voltage: 150 mV max (B Grade)
Low Quiescent Current: 6.5 mA
Available in Tape and Reel in Accordance with

EIA-481A Standard

APPLICATIONS
Flash ADC Input Amplifiers
High Speed Current DAC Interfaces
Video Buffers and Cable Drivers
Pulse Amplifiers

PRODUCT DESCRIPTION

The AD844 is a high speed monolithic operational amplifier fab­ricated using Analog Devices’ junction isolated complementary
bipolar (CB) process. It combines high bandwidth and very fast
large signal response with excellent dc performance. Although
optimized for use in current to voltage applications and as an
inverting mode amplifier, it is also suitable for use in many non­inverting applications.

The AD844 can be used in place of traditional op amps, but its
current feedback architecture results in much better ac perfor­mance, high linearity and an exceptionally clean pulse response.

This type of op amp provides a closed-loop bandwidth which is
determined primarily by the feedback resistor and is almost in­dependent of the closed-loop gain. The AD844 is free from the
slew rate limitations inherent in traditional op amps and other
current-feedback op amps. Peak output rate of change can be
over 2000 V/µs for a full 20 V output step. Settling time is typi-
cally 100 ns to 0.1%, and essentially independent of gain. The
AD844 can drive 50 Ω loads to ±2.5 V with low distortion and
is short circuit protected to 80 mA.

The AD844 is available in four performance grades and three
package options. In the 16-pin SOIC (R) package, the AD844J
is specified for the commercial temperature range of 0°C to
+70°C. The AD844A and AD844B are specified for the indus­trial temperature range of –40°C to +85°C and are available in
the cerdip (Q) package. The AD844A is also available in an 8-pin
plastic mini-DIP (N). The AD844S is specified over the military
temperature range of –55°C to +125°C. It is available in the
8-pin cerdip (Q) package. “A” and “S” grade chips and devices
processed to MIL-STD-883B, REV. C are also available.

= 500 V

L

Monolithic Op Amp

AD844

CONNECTION DIAGRAMS

8-Pin Plastic (N),

and Cerdip (Q) Packages

PRODUCT HIGHLIGHTS

1. The AD844 is a versatile, low cost component providing an
excellent combination of ac and dc performance. It may be
used as an alternative to the EL2020 and CLC400/1.

2. It is essentially free from slew rate limitations. Rise and fall
times are essentially independent of output level.

3. The AD844 can be operated from ±4.5 V to ±18 V power
supplies and is capable of driving loads down to 50 Ω, as
well as driving very large capacitive loads using an external
network.

4. The offset voltage and input bias currents of the AD844 are
laser trimmed to minimize dc errors; V
1 µV/°C and bias current drift is typically 9 nA/°C.

5. The AD844 exhibits excellent differential gain and differen­tial phase characteristics, making it suitable for a variety of
video applications with bandwidths up to 60 MHz.

6. The AD844 combines low distortion, low noise and low drift
with wide bandwidth, making it outstanding as an input am­plifier for flash A/D converters.

16-Pin SOIC

(R) Package

drift is typically

OS

REV. C

Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] Fax: [phone]

AD844–SPECIFICATIONS

(@ TA = +258C and VS = 615 V dc, unless otherwise noted)

Model Conditions Min Typ Max Min Typ Max Min Typ Max Units

AD844J/A AD844B AD844S

INPUT OFFSET VOLTAGE

T

MIN–TMAX

1

50 300 50 150 50 300 µV
75 500 75 200 125 500 µV

vs. Temperature 1 1 5 1 5 µV/°C
vs. Supply 5 V–18 V

Initial 4 20 4 10 4 20 µV/V
T

MIN–TMAX

vs. Common Mode V

= +10 V

CM

4410 4 20 µV/V

Initial 10 35 10 20 10 35 µV/V
T

MIN–TMAX

INPUT BIAS CURRENT

–Input Bias Current
T

MIN–TMAX

1

10 10 20 10 35 µV/V

200 450 150 250 200 450 nA
800 1500 750 1100 1900 2500 nA

vs. Temperature 9 9 15 20 30 nA/°C
vs. Supply 5 V–18 V

Initial 175 250 175 200 175 250 nA/V
T

MIN–TMAX

vs. Common Mode V

= +10 V

CM

220 220 240 220 300 nA/V

Initial 90 160 90 110 90 160 nA/V
T

MIN–TMAX

+Input Bias Current
T

MIN–TMAX

1

110 110 150 120 200 nA/V
150 400 100 200 100 400 nA
350 700 300 500 800 1300 nA

vs. Temperature 3 3 7 7 15 nA/°C
vs. Supply 5 V–18 V

Initial 80 150 80 100 80 150 nA/V
T

MIN–TMAX

vs. Common Mode V

= ±10 V

CM

100 100 120 120 200 nA/V

Initial 90 150 90 120 90 150 nA/V
T

MIN–TMAX

130 130 190 140 200 nA/V

INPUT CHARACTERISTICS

Input Resistance

–Input 50 65 50 65 50 65 Ω
+Input 7 10 7 10 7 10 MΩ

Input Capacitance

–Input 2 2 2 pF
+Input 2 2 2 pF

Input Voltage Range
Common Mode ±10 ±10 ±10 V

INPUT VOLTAGE NOISE f ≥ 1 kHz 2 2 2 nV/√Hz
INPUT CURRENT NOISE

–Input f ≥ 1 kHz 10 10 10 pA/√Hz
+Input f ≥ 1 kHz 12 12 12 pA/√Hz

OPEN LOOP TRANSRESISTANCE V

T

MIN–TMAX

= ±10 V

OUT

= 500 Ω 2.2 3.0 2.8 3.0 2.2 3.0 MΩ

R

LOAD

1.3 2.0 1.6 2.0 1.3 1.6 MΩ

Transcapacitance 4.5 4.5 4.5 pF

DIFFERENTIAL GAIN ERROR

2

f = 4.4 MHz 0.03 0.03 0.03 %
DIFFERENTIAL PHASE ERROR2f = 4.4 MHz 0.15 0.15 0.15 Degree
FREQUENCY RESPONSE

Small Signal Bandwidth

3

Gain = –1 60 60 60 MHz

4

Gain = –10 33 33 33 MHz

TOTAL HARMOMIC DISTORTION f = 100 kHz,

2 V rms

5

0.005 0.005 0.005 %

SETTLING TIME

10 V Output Step ±15 V Supplies

Gain = –1, to 0.1%
Gain = –10, to 0.1%

2 V Output Step ±5 V Supplies

Gain = –1, to 0.1%
Gain = –10, to 0.1%

5

6

5

6

100 100 100 ns
100 100 100 ns

110 110 110 ns
100 100 100 ns

–2–

REV. C

AD844

Model Conditions Min Typ Max Min Typ Max Min Typ Max Units

AD844J/A AD844B AD844S

OUTPUT SLEW RATE Overdriven

Input 1200 2000 1200 2000 1200 2000 V/µs

FULL POWER BANDWIDTH

= 20 V p-p

V

OUT

= 2 V p-p

V

OUT

5

5

VS = ±15 V 20 20 20 MHz
VS = ±5 V 20 20 20 MHz
THD = 3%

OUTPUT CHARACTERISTICS

Voltage R

= 500 Ω 10 11 10 11 10 11 ±V

LOAD

Short Circuit Current 80 80 80 mA
T

MIN–TMAX

60 60 60 mA

Output Resistance Open Loop 15 15 15 Ω

POWER SUPPLY

Operating Range ±4.5 ±18 ±4.5 ±18 +4.5 ±18 V
Quiescent Current 6.5 7.5 6.5 7.5 6.5 7.5 mA
T

MIN–TMAX

NOTES

1

Rated performance after a 5 minute warmup at TA = 25°C.

2

Input signal 285 mV p-p carrier (40 IRE) riding on 0 mV to 642 mV (90 IRE) ramp. RL= 100 Ω; R1, R2 = 300 Ω.

3

Input signal 0 dBm, CL = 10 pF, RL = 500 Ω, R1 = 500 Ω, R2 = 500 Ω in Figure 26.

4

Input signal 0 dBm, CL =10 pF, RL = 500 Ω, R1 = 500 Ω, R2 = 50 Ω in Figure 26.

5

CL = 10 pF, RL = 500 Ω, R1 = 1 kΩ, R2 = 1 kΩ in Figure 26.

6

CL = 10 pF, RL = 500 Ω, R1 = 500 Ω, R2 = 50 Ω in Figure 26.

Specifications subject to change without notice. All min and max specifications are guaranteed.
Specifications shown in boldface are tested on all production units at final electrical test.

ABSOLUTE MAXIMUM RATINGS

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±18 V

Power Dissipation

2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.1 W

1

Output Short Circuit Duration . . . . . . . . . . . . . . . . . Indefinite

Common-Mode Input Voltage . . . . . . . . . . . . . . . . . . . . . . ±V

Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . .6 V

Inverting Input Current

Continuous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 mA

Transient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 mA

Storage Temperature Range (Q) . . . . . . . . . .–65°C to +150°C

Storage Temperature Range (N, R) . . . . . . . .–65°C to +125°C

Lead Temperature Range (Soldering 60 sec) . . . . . . . . +300°C

7.5 8.5 7.5 8.5 8.5 9.5 mA

NOTES

1

Stresses above those listed under “Absolute Maximum Ratings” may cause
permanent damage to the device at these or any other conditions above those
indicated in the operational sections of this specification is not implied. Exposure
to absolute maximum rating conditions for extended periods may affect device
reliability.

S

2

28-Pin Plastic Package: θ
8-Pin Cerdip Package: θJA = 110°C/Watt
16-Pin SOIC Package: θJA = 100°C/Watt

= 100°C/Watt

JA

METALIZATION PHOTOGRAPH

Contact factory for latest dimensions.

Dimension shown in inches and (mm).

ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000 V

ORDERING GUIDE

Temperature Package

Model Range Option*

AD844JR 0°C to +70°C R-16
AD844JR-REEL 0°C to +70°C Tape and Reel
AD844AN –40°C to +85°C N-8
AD844AQ –40°C to +85°C Q-8
AD844BQ –40°C to +85°C Q-8
AD844SQ –55°C to +125°C Q-8
AD844SQ/883B –55°C to +125°C Q-8
5962-8964401PA –55°C to +125°C Q-8
AD844A Chips –40°C to +85°C Die

AD844S Chips –55°C to +125°C Die

*N = Plastic DIP; Q = Cerdip; R = Small Outline IC (SOIC).

REV. C

–3–

AD844–Typical Characteristics

(TA = +258C and VS = 615 V, unless otherwise noted)

Figure 1. –3 dB Bandwidth vs.
Supply Voltage R1 = R2 = 500

Figure 4. Noninverting Input Voltage
Swing vs. Supply Voltage

Ω

Figure 2. Harmonic Distortion
vs. Frequency, R1 = R2 = 1 k

Figure 5. Output Voltage Swing
vs. Supply Voltage

Ω

Figure 3. Transresistance
vs. Temperature

Figure 6. Quiescent Supply Current
vs. Temperature and Supply Voltage

Figure 7. Inverting Input Bias Cur­rent (I
Bias Current (I

) and Noninverting Input

BN

) vs. Temperature

BP

Figure 8. Output Impedance vs.
Frequency, Gain = –1, R1 = R2 = 1 k

–4–

Figure 9. –3 dB Bandwidth vs.

Ω

Temperature, Gain = –1,
R1 = R2 = 1 k

Ω

REV. C