Analog Devices AD790SQ, AD790KN, AD790JR-REEL7, AD790JR-REEL, AD790JR Datasheet

Fast, Precision

a

FEATURES
45 ns max Propagation Delay
Single 5 V or Dual ⴞ15 V Supply Operation
CMOS or TTL Compatible Output
250 ␮V max Input Offset Voltage
500 ␮V max Input Hysteresis Voltage
15 V max Differential Input Voltage
Onboard Latch
60 mW Power Dissipation
Available in 8-Pin Plastic and Hermetic Cerdip

Packages

Available in Tape and Reel in Accordance with

EIA-481A Standard

APPLICATIONS
Zero-Crossing Detectors
Overvoltage Detectors
Pulse-Width Modulators
Precision Rectifiers
Discrete A/D Converters
Delta-Sigma Modulator A/Ds

CONNECTION DIAGRAMS

8-Pin Plastic Mini-DIP (N)

and Cerdip (Q) Packages

+V

1

S

+IN

2

–IN

3

–V

45

S

AD790

+

–

8-Pin SOIC (R) Package

V

LOGIC

+V

+IN

1

2

3

S

4

AD790

+

–

OUTPUT

Comparator

AD790

V

8

LOGIC

OUTPUT

7

6

GROUND

LATCH

GROUND

8

7

LATCH

–V

6

S

5

–IN

PRODUCT DESCRIPTION

The AD790 is a fast (45 ns), precise voltage comparator, with a
number of features that make it exceptionally versatile and easy
to use. The AD790 may operate from either a single 5 V supply
or a dual ±15 V supply. In the single-supply mode, the AD790’s
inputs may be referred to ground, a feature not found in other
comparators. In the dual-supply mode it has the unique ability
of handling a maximum differential voltage of 15 V across its in­put terminals, easing their interfacing to large amplitude and
dynamic signals.

This device is fabricated using Analog Devices’ Complementary
Bipolar (CB) process—which gives the AD790’s combination
of fast response time and outstanding input voltage resolution
(1 mV max). To preserve its speed and accuracy, the AD790
incorporates a “low glitch” output stage that does not exhibit
the large current spikes normally found in TTL or CMOS output
stages. Its controlled switching reduces power supply disturbances
that can feed back to the input and cause undesired oscillations.
The AD790 also has a latching function which makes it suitable
for applications requiring synchronous operation.

The AD790 is available in five performance grades. The
AD790J and the AD790K are rated over the commercial tem­perature range of 0°C to 70°C. The AD790A and AD790B are
rated over the industrial temperature range of –40°C to +85°C.
The AD790S is rated over the military temperature range of
–55°C to +125°C.

PRODUCT HIGHLIGHTS

1. The AD790’s combination of speed, precision, versatility
and low cost makes it suitable as a general purpose compara­tor in analog signal processing and data acquisition systems.

2. Built-in hysteresis and a low-glitch output stage minimize the
chance of unwanted oscillations, making the AD790 easier to
use than standard open-loop comparators.

3. The hysteresis combined with a wide input voltage range
enables the AD790 to respond to both slow, low level (e.g.,
10 mV) signals and fast, large amplitude (e.g., 10 V) signals.

4. A wide variety of supply voltages is acceptable for operation
of the AD790, ranging from single 5 V to dual +5 V/–12 V,
± 5 V, or +5 V/± 15 V supplies.

5. The AD790’s power dissipation is the lowest of any compara­tor in its speed range.

6. The AD790’s output swing is symmetric between V

LOGIC

and ground, thus providing a predictable output under a
wide range of input and output conditions.

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 that
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] www.analog.com
Fax: [phone] © Analog Devices, Inc., 2002

AD790–SPECIFICATIONS

DUAL SUPPLY

(Operation @ 25ⴗC and +VS = 15 V, –VS = –15 V, V

= 5 V unless otherwise noted.)

LOGIC

AD790J/A AD790K/B AD790S

Parameter Conditions Min Typ Max Min Typ Max Min Typ Max Unit

RESPONSE CHARACTERISTIC 100 mV Step

Propagation Delay, t

PD

5 mV Overdrive 40 45 40 45 40 45 ns
T

MIN

to T

MAX

45/50 45/50 60 ns

OUTPUT CHARACTERISTICS

Output HIGH Voltage, V

OH

1.6 mA Source 4.65 4.65 4.65

6.4 mA Source 4.3 4.45 4.3 4.45 4.3 4.45 V

Output LOW Voltage, V

OL

to T

T

MIN

MAX

1.6 mA Sink 0.35 0.35 0.35 V

4.3/4.3 4.3 4.3 V

6.4 mA Sink 0.44 0.5 0.44 0.5 0.44 0.5 V
T

INPUT CHARACTERISTICS

Offset Voltage

Hysteresis

1

2

to T

MIN

MAX

to T

T

MIN

MIN

to T

MAX

MAX

0.3 0.4 0.6 0.3 0.4 0.5 0.3 0.4 0.65 mV

T

0.5/0.5 0.5 0.5 V

0.2 1.0 0.05 0.25 0.2 1.0 mV

1.5 0.5 1.5 mV

Bias Current Either Input 2.5 5 1.8 3.5 2.5 5 µA

to T

T

MIN

MAX

6.5 4.5 7 µA

Offset Current 0.04 0.25 0.02 0.15 0.04 0.25 µA

to T

T

MIN

MAX

0.3 0.2 0.4 µA

Power Supply

Rejection Ratio DC V

± 20% 80 90 88 100 80 90 dB

S

to T

T

MIN

MAX

76 88 85 93 76 85 dB

Input Voltage Range

Differential Voltage V

≤± 15 V ⴞV

S

Common Mode –V

S

S

+VS–2 V –V

S

ⴞV

S

+VS–2 V –V

ⴞV

S

+VS–2 V V

V

S

Common Mode

Rejection Ratio –10 V<V

CM

80 95 88 105 80 95 dB

<+10 V

to T

T

MIN

MAX

76 90 85 100 76 88 dB

Input Impedance 20储220储220储2MΩ储pF

LATCH CHARACTERISTICS

Latch Hold Time, t
Latch Setup Time, t
LOW Input Level, V

H

S

IL

HIGH Input Level, V

T

to T

MIN

MIN

to T

MAX

MA X

IH

T

25 35 25 35 25 35 ns
510 510 510 ns

0.8 0.8 0.8 V

1.6 1.6 1.6 V

Latch Input Current 2.3 5 2.3 3.5 2.3 5 µA

T

SUPPLY CHARACTERISTICS

Diff Supply Voltage

3

Logic Supply T

V
T

to T

MIN

LOGIC

to T

MIN

to T

MIN

MAX

= 5 V

MAX

MAX

4.5 33 4.5 33 4.7 33 V

4.0 7 4.0 7 4.2 7 V

7 58µA

Quiescent Current

+V
–V
V

LOGIC

S

S

+VS = 15 V 8 10 8 10 8 10 mA
–VS = –15 V 4 5 4 5 4 5 mA
V

= 5 V 2 3.3 2 3.3 2 3.3 mA

LOGIC

Power Dissipation 242 242 242 mW

TEMPERATURE RANGE

Rated Performance T

NOTES

1

Defined as the average of the input voltages at the low to high and high to low transition points. Refer to Figure 6.

2

Defined as half the magnitude between the input voltages at the low to high and high to low transition points. Refer to Figure 6.

3

+VS must be no lower than (V

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

–0.5 V) in any supply operating conditions, except during power up.

LOGIC

MIN

to T

MAX

0 to 70/–40 to +85 0 to 70/–40 to +85 –55 to +125 °C

–2–

REV. C

AD790

SINGLE SUPPLY

(Operation @ 25ⴗC and +VS = V

= 5 V, –VS = 0 V unless otherwise noted.)

LOGIC

1

AD790J/A AD790K/B AD790S

Parameter Conditions Min Typ Max Min Typ Max Min Typ Max Unit

RESPONSE CHARACTERISTIC 100 mV Step

Propagation Delay, t

PD

5 mV Overdrive 45 50 45 50 45 50 ns
T

MIN

to T

MAX

50/60 50/60 65 ns

OUTPUT CHARACTERISTICS

Output HIGH Voltage, V

OH

1.6 mA Source 4.65 4.65 4.65

6.4 mA Source 4.3 4.45 4.3 4.45 4.3 4.45 V

Output LOW Voltage, V

OL

to T

T

MIN

MAX

1.6 mA Sink 0.35 0.35 0.35 V

4.3 4.3 4.3 V

6.4 mA Sink 0.44 0.5 0.44 0.5 0.44 0.5 V
T

INPUT CHARACTERISTICS

Offset Voltage

Hysteresis

2

3

to T

MIN

MAX

to T

T

MIN

MIN

to T

MAX

MAX

0.3 0.5 0.75 0.3 0.5 0.65 0.3 0.7 1.0 mV

T

0.5 0.5 0.5 V

0.45 1.5 0.35 0.6 0.45 1.5 mV

2.0 0.85 2.0 mV

Bias Current Either Input 2.7 5 2.0 3.5 2.7 5 µA

to T

T

MIN

MAX

7 58µA

Offset Current 0.04 0.25 0.02 0.15 0.04 0.25 µA

to T

T

MIN

MAX

0.3 0.2 0.4 µA

Power Supply

Rejection Ratio DC 4.5 V≤V

T

≤5.5 V 80 90 86 100 80 90 dB

S

MIN

to T

MAX

76/76 88 82 93 76 85 dB

Input Voltage Range

Differential Voltage ⴞV
Common Mode 0 +V

S

–2 V 0 +VS–2 V 0 +VS–2 V V

S

ⴞV

S

ⴞV

V

S

Input Impedance 20储220储220储2MΩ储pF

LATCH CHARACTERISTICS

Latch Hold Time, t
Latch Setup Time, t
LOW Input Level, V

H

S

IL

HIGH Input Level, V

T

to T

MIN

MIN

to T

MAX

MAX

IH

T

25 35 25 35 25 35 ns
510 510 510 ns

0.8 0.8 0.8 V

1.6 1.6 1.6 V

Latch Input Current 2.3 5 2.3 3.5 2.3 5 µA

T

SUPPLY CHARACTERISTICS

Supply Voltage

4

to T

MIN

MAX

T

MIN

to T

MAX

4.5 7 4.5 7 4.7 7 V

7 58µA

Quiescent Current 10 12 10 12 10 12 mA
Power Dissipation 60 60 60 mW

TEMPERATURE RANGE

Rated Performance T

NOTES

1

Pin 1 tied to Pin 8, and Pin 4 tied to Pin 6.

2

Defined as the average of the input voltages at the low to high and high to low transition points. Refer to Figure 6.

3

Defined as half the magnitude between the input voltages at the low to high and high to low transition points. Refer to Figure 6.

4

–VS must not be connected above ground.

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

MIN

to T

MAX

0 to 70/–40 to +85 0 to 70/–40 to +85 –55 to +125 °C

REV. C

–3–

AD790

–

ABSOLUTE MAXIMUM RATINGS

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

Internal Power Dissipation

2

. . . . . . . . . . . . . . . . . . . 500 mW

1, 2

Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . ± 16.5 V

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

Storage Temperature Range

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

(Q) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to +150°C

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

Logic Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V

NOTES

1

Stresses above those listed under “Absolute Maximum Ratings” may cause perma­nent damage to the device. This is a stress rating only and functional operation of
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.

2

Thermal characteristics: plastic N-8 package: θJA = 90°C/watt; ceramic Q-8
package: θJA = 110°C/watt, θJC = 30°C/watt. SOIC (R-8) package: θJA = 160°C
watt; θJC = 42°C/watt.

+

+IN

–IN

0.1µF

2

3

15V

1

AD790

4

–

15V

5V

+

0.1µF

8

0.1µF

6

5

LATCH

(OPTIONAL)

510

7

Ω

OUTPUT

Figure 1. Basic Dual Supply
Configuration (N, Q Package Pinout)

ORDERING GUIDE

Temperature Package Package

Model Range Description Option

AD790JN 0°C to 70°C Plastic DIP N-8
AD790JR 0°C to 70°C SOIC SO-8
AD790JR-REEL 0°C to 70°C Reel
AD790JR-REEL7 0°C to 70°C SOIC R-8
AD790KN

*

0°C to 70°C Plastic DIP N-8
AD790AQ –40°C to +85°C Cerdip Q-8
AD790BQ

*

–40°C to +85°C Cerdip Q-8
AD790SQ –55°C to +125°C Cerdip Q-8

*

Not for new designs; obsolete April 2002.

For military processed devices, please refer to the standard Mi­crocircuit Drawing (SMD) available at
www.dscc.dla.mil/programs/milspec/default.asp

SMD Part Number ADI Equivalent

5962-9150501MPA

*

Not for new designs; obsolete April 2002.

+IN

IN

2

3

*

+

1

AD790

4

5V

8

0.1µF

5

6

AD790 SQ/883

LATCH

(OPTIONAL)

510

7

Ω

OUTPUT

Figure 2. Basic Single Supply
Configuration (N, Q Package Pinout)

10kΩ

+15V

2

AD790

3

+5V

1

4

–15V

–

5V

VOLTAGE

SOURCE

0.1µF

1k

8

5

6

0.1µF

TEK
7904

7

SCOPE

PULSE

GENERATOR

–1.3V

–1.7V

HP8112

0.1µF

130Ω

HP2835

–5V

0.1µF

–100mV

25Ω

MPS

571

650Ω 400Ω 50Ω

–5mV

10Ω

Figure 3. Response Time Test Circuit (N, Q Package Pinout)

–4–

REV. C