Analog Devices AD630 e Datasheet

a

Balanced Modulator/Demodulator

AD630

FEATURES
Recovers Signal from 100 dB Noise
2 MHz Channel Bandwidth
45 V/␮s Slew Rate
–120 dB Crosstalk @ 1 kHz
Pin Programmable, Closed-Loop Gains of ⴞ1 and ⴞ2

0.05% Closed-Loop Gain Accuracy and Match
100 ␮V Channel Offset Voltage (AD630BD)
350 kHz Full Power Bandwidth
Chips Available

PRODUCT DESCRIPTION

The AD630 is a high precision balanced modulator that combines
a flexible commutating architecture with the accuracy and tem­perature stability afforded by laser wafer trimmed thin film
resistors. Its signal processing applications include balanced
modulation and demodulation, synchronous detection, phase
detection, quadrature detection, phase-sensitive detection,
lock-in amplification, and square wave multiplication. A network
of on-board applications resistors provides precision closed-loop
gains of ± 1 and ± 2 with 0.05% accuracy (AD630B). These
resistors may also be used to accurately configure multiplexer
gains of +1, +2, +3, or +4. Alternatively, external feedback may
be employed, allowing the designer to implement high gain or
complex switched feedback topologies.

The AD630 can be thought of as a precision op amp with two
independent differential input stages and a precision comparator
that is used to select the active front end. The rapid response
time of this comparator coupled with the high slew rate and fast
settling of the linear amplifiers minimize switching distortion. In
addition, the AD630 has extremely low crosstalk between chan­nels of –100 dB @ 10 kHz.

The AD630 is used in precision signal processing and instru­mentation applications that require wide dynamic range. When
used as a synchronous demodulator in a lock-in amplifier
configuration, it can recover a small signal from 100 dB of inter­fering noise (see Lock-In Amplifier Applications section). Although
optimized for operation up to 1 kHz, the circuit is useful at
frequencies up to several hundred kilohertz.

Other features of the AD630 include pin programmable frequency
compensation, optional input bias current compensation resis­tors, common-mode and differential-offset voltage adjustment,
and a channel status output that indicates which of the two
differential inputs is active. This device is now available to
Standard Military Drawing (DESC) numbers 5962-8980701RA
and 5962-89807012A.

FUNCTIONAL BLOCK DIAGRAM

RINA

CH A+

CH A–

R

IN

CH B+

CH B–

SEL B

SEL A

CM OFF

2.5k⍀

1

2

20

2.5k⍀

17

B

18

19

9

10

ADJ

6

AMP A

AMP B

COMP

CM OFF

ADJ

5

A

B

DIFF OFF

ADJ

–V

8

–V

S

DIFF OFF

ADJ

34

AD630

10k⍀

10k⍀

5k⍀

12

COMP

+V

11

13

V

14

R

15

R

16

R

CHANNEL

7

STATUS
B/A

S

OUT

B

F

A

PRODUCT HIGHLIGHTS

1. The configuration of the AD630 makes it ideal for signal
processing applications, such as balanced modulation and
demodulation, lock-in amplification, phase detection, and
square wave multiplication.

2. The application flexibility of the AD630 makes it the best
choice for applications that require precisely fixed gain,
switched gain, multiplexing, integrating-switching functions,
and high speed precision amplification.

3. The 100 dB dynamic range of the AD630 exceeds that of any
hybrid or IC balanced modulator/demodulator and is compa­rable to that of costly signal processing instruments.

4. The op amp format of the AD630 ensures easy implementa­tion of high gain or complex switched feedback functions.
The application resistors facilitate the implementation of
most common applications with no additional parts.

5. The AD630 can be used as a 2-channel multiplexer with
gains of +1, +2, +3, or +4. The channel separation of
100 dB @ 10 kHz approaches the limit achievable with an
empty IC package.

6. The AD630 has pin strappable frequency compensation (no
external capacitor required) for stable operation at unity gain
without sacrificing dynamic performance at higher gains.

7. Laser trimming of comparator and amplifying channel offsets
eliminates the need for external nulling in most cases.

REV. E

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. Trademarks and
registered trademarks are the property of their respective owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.

AD630–SPECIFICATIONS

(@ 25ⴗC and ⴞVS = ⴞ15 V, unless otherwise noted.)

AD630J/AD630A AD630K/AD630B AD630S

Model Min Typ Max Min Typ Max Min Typ Max Unit

GAIN

Open-Loop Gain 90 110 100 120 90 110 dB
± 1, ± 2 Closed-Loop Gain Error 0.1 0.05 0.1 %
Closed-Loop Gain Match 0.1 0.05 0.1 %
Closed-Loop Gain Drift 2 2 2 ppm/°C

CHANNEL INPUTS

VIN Operational Limit

1

(–VS + 4 V) to (+VS – 1 V) (–VS + 4 V) to (+VS – 1 V) (–VS + 4 V) to (+VS – 1 V) V
Input Offset Voltage 500 100 500 µV
Input Offset Voltage

T

MIN

to T

MAX

800 160 1000 µV
Input Bias Current 100 300 100 300 100 300 nA
Input Offset Current 10 50 10 50 10 50 nA
Channel Separation @ 10 kHz 100 100 100 dB

COMPARATOR

V

Operational Limit

IN

1

(–VS + 3 V) to (+VS – 1.5 V) (–VS + 3 V) to (+VS – 1.5 V) (–VS + 3 V) to (+VS – 1.3 V) V
Switching Window ± 1.5 ±1.5 ± 1.5 mV
Switching Window

T

MIN

to T

MAX

± 2.0 ±2.0 ± 2.5 mV
Input Bias Current 100 300 100 300 100 300 nA
Response Time (–5 mV to +5 mV Step) 200 200 200 ns
Channel Status

I

@ VOL = –VS + 0.4 V

SINK

2

1.6 1.6 1.6 mA

Pull-Up Voltage (–VS + 33 V) (–VS + 33 V) (–VS + 33 V) V

DYNAMIC PERFORMANCE

Unity Gain Bandwidth 2 2 2 MHz
Slew Rate

3

45 45 45 V/µs

Settling Time to 0.1% (20 V Step) 3 3 3 µs

OPERATING CHARACTERISTICS

Common-Mode Rejection 85 105 90 110 90 110 dB
Power Supply Rejection 90 110 90 110 90 110 dB
Supply Voltage Range ± 5 ± 16.5 ± 5 ±16.5 ± 5 ± 16.5 V
Supply Current 4 5 4 5 4 5 mA

OUTPUT VOLTAGE, @ RL = 2 kΩ

T

MIN

to T

MAX

± 10 ± 10 ± 10 V

Output Short-Circuit Current 25 25 25 mA

TEMPERATURE RANGES

Rated Performance–N Package 0 70 0 70 N/A °C

Rated Performance–D Package –25 +85 –25 +85 –55 +125 °C

NOTES

1

If one terminal of each differential channel or comparator input is kept within these limits the other terminal may be taken to the positive supply.

2

I

@ VOL = (–VS + 1); V is typically 4 mA.

SINK

3

Pin 12 Open. Slew rate with Pin 12 and Pin 13 shorted is typically 35 V/µs.

Specifications subject to change without notice.

–2–

REV. E

AD630

20 19123

18

14

15

16

17

4

5

6

7

8

910111213

TOP VIEW

(Not to Scale)

AD630

DIFF OFF ADJ

CM OFF ADJ

CM OFF ADJ

CHANNEL STATUS B/A

–V

S

CH B+

R

IN

B

R

A

R

F

R

B

DIFF

OFF ADJ

CH A+

R

IN

A

CH A–

CH B–

SEL B

SEL A

+V

S

COMP

V

OUT

ABSOLUTE MAXIMUM RATINGS

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

Internal Power Dissipation . . . . . . . . . . . . . . . . . . . . 600 mW

Output Short-Circuit to Ground . . . . . . . . . . . . . . . Indefinite

Storage Temperature, Ceramic Package . . . –65°C to +150°C

Storage Temperature, Plastic Package . . . . . –55°C to +125°C

Lead Temperature Range (Soldering, 10 sec) . . . . . . . . 300°C

Maximum Junction Temperature . . . . . . . . . . . . . . . . . 150°C

ORDERING GUIDE

Model Temperature Ranges Package Description Package Option

AD630JN 0°C to 70°C PDIP N-20
AD630KN 0°C to 70°C PDIP N-20
AD630AR –25°C to +85°C SOIC R-20
AD630AR-REEL –25°C to +85°CSOIC 13" Tape and Reel R-20
AD630AD –25°C to +85°C SBDIP D-20
AD630BD –25°C to +85°C SBDIP D-20
AD630SD –55°C to +125°C SBDIP D-20
AD630SD/883B –55°C to +125°C SBDIP D-20
5962-8980701RA –55°C to +125°C SBDIP D-20
AD630SE/883B –55°C to +125°C CLCC E-20A
5962-89807012A –55°C to +125°C CLCC E-20A
AD630JCHIPS 0°C to 70°C Chip
AD630SCHIPS –55°C to +125°C Chip

THERMAL CHARACTERISTICS

␪

JC

␪

JA

20-Lead PDIP (N) 24°C/W 61°C/W
20-Lead Ceramic DIP (D) 35°C/W 120°C/W
20-Lead Leadless Chip Carrier LCC (E) 35°C/W 120°C/W
20-Lead SOIC (R-20) 38°C/W 75°C/W

CHIP METALLIZATION AND PINOUT

Dimensions shown in inches and (millimeters).

Contact factory for latest dimensions.

CHIP AVAILABILITY

The AD630 is available in laser trimmed, passivated chip
form. The figure above shows the AD630 metallization pattern,
bonding pads and dimensions. AD630 chips are available; con­sult factory for details.

CHANNEL STATUS B/A

PIN CONFIGURATIONS

20-Lead SOIC, PDIP, and CERDIP

RINA

CH A+

DIFF OFF ADJ

DIFF OFF ADJ

CM OFF ADJ

CM OFF ADJ

–V

SEL B

SEL A

1

2

3

4

5

6

7

8

S

9

10

AD630

TOP VIEW

(Not to Scale)

20

19

18

17

16

15

14

13

12

11

CH A–

CH B–

CH B+

B

R

IN

R

A

R

F

R

B

V

OUT

COMP

+V

S

20-Terminal CLCC

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the AD630 features proprietary ESD protection circuitry, permanent damage may occur on devices
subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are
recommended to avoid performance degradation or loss of functionality.

REV. E

–3–

AD630

(⍀)

)

)

)

)

AD630–Typical Performance Characteristics

15

R

=

2k⍀

L

C

= 100pF

L

10

V

i

5

OUTPUT VOLTAGE (ⴞV)

0

1k 10k 1M

5k⍀5k⍀

2k⍀

100pF

FREQUENCY (Hz

100k

V

O

TPC 1. Output Voltage vs. Frequency

120

100

80

60

40

20

COMMON-MODE REJECTION (dB)

0

110

100 1k 10k

FREQUENCY (Hz

100k

TPC 4. Common-Mode Rejection
vs. Frequency

15

CL = 100pF

V

5k⍀

i

CAP IN

f = 1kHz

5k⍀

R

L

V

100pF

O

10

5

OUTPUT VOLTAGE (ⴞV)

0

1

100 1k 10k 100k 1M

10

RESISTIVE LOAD

TPC 2. Output Voltage vs. Resistive
Load

60

UNCOMPENSATED

40

20

0

(V/␮s)

O

dt

dV

TPC 5.

–20

–40

–60

–5 –3

–4

dV

O

dt

–2 –1
INPUT VOLTAGE (V

vs. Input Voltage

COMPENSATED

1

023 5

4

18

5k⍀

5k⍀

V

15

i

2k⍀

10

5

OUTPUT VOLTAGE (ⴞV)

0

051015

SUPPLY VOLTAGE (ⴞV)

V

O

100pF

f = 1kHz
C

= 100pF

L

TPC 3. Output Voltage Swing vs.
Supply Voltage

120

100

80

60

COMPENSATED

40

OPEN LOOP GAIN (dB)

20

0

0

100

10 1k 100k10k

FREQUENCY (Hz

UNCOMPENSATED

1M

10M

0

45

90

135

180

TPC 6. Gain and Phase vs. Frequency

OPEN LOOP PHASE (ⴗC)

–4–

–4–

REV. E

REV. E