Analog Devices AD824 c Datasheet

Single Supply, Rail-to-Rail

1

2

14

13

5

6

7

10

9

8

3

4

12

11

TOP VIEW

(Not to Scale)

AD824

OUT A

–IN A

+IN A

V+

+IN B

–IN B

OUT B

OUT D

–IN D

+IN D

V–

+IN C

–IN C

OUT C

Low Power, FET-Input Op Amp

AD824

FEATURES
Single Supply Operation: 3 V to 30 V
Very Low Input Bias Current: 2 pA
Wide Input Voltage Range
Rail-to-Rail Output Swing
Low Supply Current: 500 A/Amp
Wide Bandwidth: 2 MHz
Slew Rate: 2 V/s
No Phase Reversal

APPLICATIONS
Photo Diode Preamplifier
Battery Powered Instrumentation
Power Supply Control and Protection
Medical Instrumentation
Remote Sensors
Low Voltage Strain Gage Amplifiers
DAC Output Amplifier

GENERAL DESCRIPTION

The AD824 is a quad, FET input, single supply amplifier, fea­turing rail-to-rail outputs. The combination of FET inputs and
rail-to-rail outputs makes the AD824 useful in a wide variety of
low voltage applications where low input current is a primary
consideration.

The AD824 is guaranteed to operate from a 3 V single supply
up to ±15 V dual supplies. AD824AR-3V Parametric Perfor­mance at 3 V is fully guaranteed.

Fabricated on ADI’s complementary bipolar process, the AD824
has a unique input stage that allows the input voltage to safely
extend beyond the negative supply and to the positive supply
without any phase inversion or latchup. The output voltage
swings to within 15 mV of the supplies. Capacitive loads to
350 pF can be handled without oscillation.

PIN CONFIGURATIONS

14-Lead Epoxy SOIC

(R Suffix)

16-Lead Epoxy SOIC

(R Suffix)

OUT A

–IN A

+IN A

V+

+IN B

–IN B

OUT B

NC

1

2

3

4

AD824

5

6

7

8

NC = NO CONNECT

16

15

14

13

12

11

10

9

OUT D

–IN D

+IN D

V–

+IN C

–IN C

OUT C

NC

The FET input combined with laser trimming provides an input
that has extremely low bias currents with guaranteed offsets
below 1 mV. This enables high accuracy designs even with
high source impedances. Precision is combined with low
noise, making the AD824 ideal for use in battery powered
medical equipment.

Applications for the AD824 include portable medical equipment,
photo diode preamplifiers and high impedance transducer
amplifiers.

The ability of the output to swing rail-to-rail enables designers
to build multistage filters in single supply systems and maintain
high signal-to-noise ratios.

The AD824 is specified over the extended industrial (–40∞C to
+85∞C) temperature range and is available in narrow 14-lead
and 16-lead SOIC packages.

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

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2003 Analog Devices, Inc. All rights reserved.

AD824–SPECIFICATIONS

ELECTRICAL SPECIFICATIONS

(@ VS = 5.0 V, VCM = 0 V, V

= 0.2 V, TA = 25C unless otherwise noted)

OUT

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage AD824A V

Input Bias Current I

Input Offset Current I

B

OS

OS

T

to T

MIN

T

MIN

T

MIN

to T

to T

MAX

MAX

MAX

0.1 1.0 mV

1.5 mV
212pA
300 4000 pA
210pA
300 pA

Input Voltage Range –0.2 3.0 V
Common-Mode Rejection Ratio CMRR V

Input Impedance 10
Large Signal Voltage Gain A

VO

= 0 V to 2 V 66 80 dB

CM

= 0 V to 3 V 60 74 dB

V

CM

T

MIN

to T

MAX

60 dB

13

储3.3 W储pF

VO = 0.2 V to 4.0 V
R

= 2 kW 20 40 V/mV

L

R

= 10 kW 50 100 V/mV

L

= 100 kW 250 1000 V/mV

R

L

T

MIN

to T

= 100 kW 180 400 V/mV

MAX, RL

Offset Voltage Drift DVOS/DT2mV/∞C

OUTPUT CHARACTERISTICS

Output Voltage High V

Output Voltage Low V

Short Circuit Limit I

Open-Loop Impedance Z

OH

OL

SC

OUT

I

= 20 mA 4.975 4.988 V

SOURCE

to T

T

MIN

I

SOURCE

T

MIN

I

SINK

T

MIN

I

SINK

T

MIN

MAX

= 2.5 mA 4.80 4.85 V

to T

MAX

= 20 mA1525mV

to T

MAX

= 2.5 mA 120 150 mV

to T

MAX

4.97 4.985 V

4.75 4.82 V

20 30 mV

140 200 mV

Sink/Source ±12 mA

to T

T

MIN

MAX

±10 mA

f = 1 MHz, AV = 1 100 W

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 12 V 70 80 dB

T

Supply Current/Amplifier I

SY

to T

MIN

T

MIN

to T

MAX

MAX

66 dB

500 600 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 10 kW, AV = 1 2 V/ms
Full-Power Bandwidth BW
Settling Time t

S

P

1% Distortion, VO = 4 V p-p 150 kHz
V

= 0.2 V to 4.5 V, to 0.01% 2.5 ms

OUT

Gain Bandwidth Product GBP 2 MHz
Phase Margin foNo Load 50 Degrees
Channel Separation CS f = 1 kHz, RL = 2 kW –123 dB

NOISE PERFORMANCE

Voltage Noise en p-p 0.1 Hz to 10 Hz 2 mV p-p
Voltage Noise Density e
Current Noise Density i

n

n

f = 1 kHz 16 nV/÷Hz
f = 1 kHz 0.8 fA/÷Hz

Total Harmonic Distortion THD f = 10 kHz, RL = 0, AV = +1 0.005 %

–2–

REV. C

AD824

ELECTRICAL SPECIFICATIONS

(@ VS = 15.0 V, V

= 0 V, TA = 25C unless otherwise noted)

OUT

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage AD824A V

Input Bias Current I

Input Offset Current I

OS

B

I

B

OS

to T

T

MIN

MAX

VCM = 0 V 4 35 pA
T

to T

MIN

MAX

VCM = –10 V 25 pA

T

to T

MIN

MAX

0.5 2.5 mV

0.6 4.0 mV

500 4000 pA

320 pA

500 pA
Input Voltage Range –15 13 V
Common-Mode Rejection Ratio CMRR V

Input Impedance 10
Large Signal Voltage Gain A

VO

= –15 V to 13 V 70 80 dB

CM

T

MIN

to T

MAX

66 dB

13

储3.3 W储pF

Vo = –10 V to +10 V;
R

= 2 kW 12 50 V/mV

L

= 10 kW 50 200 V/mV

R

L

R

= 100 kW 300 2000 V/mV

L

T

MIN

to T

= 100 kW 200 1000 V/mV

MAX, RL

Offset Voltage Drift DVOS/DT2mV/∞C

OUTPUT CHARACTERISTICS

Output Voltage High V

Output Voltage Low V

Short Circuit Limit I
Open-Loop Impedance Z

OH

OL

SC

OUT

I

= 20 mA 14.975 14.988 V

SOURCE

T

to T

MIN

I

SOURCE

T

MIN

I

SINK

T

MIN

I

SINK

T

MIN

Sink/Source, T

MAX

= 2.5 mA 14.80 14.85 V

to T

MAX

= 20 mA –14.985 –14.975 V

to T

MAX

= 2.5 mA –14.88 –14.85 V

to T

MAX

MIN

to T

MAX

14.970 14.985 V

14.75 14.82 V

–14.98 –14.97 V

–14.86 –14.8 V

±8 ±20 mA

f = 1 MHz, AV = 1 100 W

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 15 V 70 80 dB

T

Supply Current/Amplifier I

SY

to T

MIN

MAX

VO = 0 V 560 625 mA
T

to T

MIN

MAX

68 dB

675 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL = 10 kW, AV = 1 2 V/ms
Full-Power Bandwidth BW
Settling Time t

S

P

1% Distortion, VO = 20 V p-p 33 kHz
V

= 0 V to 10 V, to 0.01% 6 ms

OUT

Gain Bandwidth Product GBP 2 MHz
Phase Margin fo50Degrees
Channel Separation CS f = 1 kHz, RL =2 kW –123 dB

NOISE PERFORMANCE

Voltage Noise en p-p 0.1 Hz to 10 Hz 2 mV p-p
Voltage Noise Density e
Current Noise Density i

n

n

Total Harmonic Distortion THD f =10 kHz, V

f = 1 kHz 16 nV/÷Hz
f = 1 kHz 1.1 fA/÷Hz

= 3 V rms,

O

RL = 10 kW 0.005 %

REV. C

–3–

AD824–SPECIFICATIONS

ELECTRICAL SPECIFICATIONS

(@ VS = 3.0 V, VCM = 0 V, V

= 0.2 V, TA = 25C unless otherwise noted)

OUT

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage AD824A -3 V V

Input Bias Current I

Input Offset Current I

B

OS

OS

T

to T

MIN

T

MIN

T

MIN

to T

to T

MAX

MAX

MAX

0.2 1.0 mV

1.5 mV
212pA
250 4000 pA
210pA
250 pA

Input Voltage Range 0 1 V
Common-Mode Rejection Ratio CMRR V

Input Impedance 10
Large Signal Voltage Gain A

VO

= 0 V to 1 V 58 74 dB

CM

T

MIN

to T

MAX

56 dB

13

储3.3 W储pF

VO = 0.2 V to 2.0 V
R

= 2 kW 10 20 V/mV

L

= 10 kW 30 65 V/mV

R

L

R

= 100 kW 180 500 V/mV

L

T

MIN

to T

= 100 kW 90 250 V/mV

MAX, RL

Offset Voltage Drift DVOS/DT2mV/∞C

OUTPUT CHARACTERISTICS

Output Voltage High V

Output Voltage Low V

Short Circuit Limit I

Open-Loop Impedance Z

I

OH

OL

SC

SC

OUT

I

= 20 mA 2.975 2.988 V

SOURCE

T

to T

MIN

I

SOURCE

T

MIN

I

SINK

T

MIN

I

SINK

T

MIN

MAX

= 2.5 mA 2.8 2.85 V

to T

MAX

= 20 mA1525mV

to T

MAX

= 2.5 mA 120 150 mV

to T

MAX

2.97 2.985 V

2.75 2.82 V

20 30 mV

140 200 mV

Sink/Source ±8mA
Sink/Source, T

MIN

to T

MAX

±6mA

f = 1 MHz, AV = 1 100 W

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 12 V, 70 dB

Supply Current/Amplifier I

SY

to T

T

MIN

MAX

VO = 0.2 V, T

MIN

to T

MAX

66 dB

500 600 mA

DYNAMIC PERFORMANCE

Slew Rate SR RL =10 kW, AV = 1 2 V/ms
Full-Power Bandwidth BW
Settling Time t

S

P

1% Distortion, VO = 2 V p-p 300 kHz
V

= 0.2 V to 2.5 V, to 0.01% 2 ms

OUT

Gain Bandwidth Product GBP 2 MHz
Phase Margin fo50Degrees
Channel Separation CS f = 1 kHz, RL = 2 kW –123 dB

NOISE PERFORMANCE

Voltage Noise en p-p 0.1 Hz to 10 Hz 2 mV p-p
Voltage Noise Density e
Current Noise Density i

n

n

f = 1 kHz 16 nV/÷Hz

0.8 fA/÷Hz

Total Harmonic Distortion THD f = 10 kHz, RL = 0, AV = +1 0.01 %

–4–

REV. C

AD824

R1 R2

+IN

J1 J2

R13

–IN

R15

Q4

Q5

Q6

R9

I5

V

CC

C3

Q7

C2

Q22

Q19

Q21 Q27

Q18 Q29

Q20

Q23

R7

C4

V

OUT

Q24 Q25

Q31

Q28

R17

Q26

C1

I4I3I2I1

R12 R14

Q2

Q8

Q3

V

EE

I6

WAFER TEST LIMITS

(@ VS = 5.0 V, VCM = 0 V, TA = 25C unless otherwise noted)

Parameter Symbol Conditions Limit Unit

Offset Voltage V
Input Bias Current I
Input Offset Current I
Input Voltage Range V

OS

B

OS

CM

Common-Mode Rejection Ratio CMRR V

= 0 V to 2 V 66 dB min

CM

1.0 mV max
12 pA max
20 pA
–0.2 to 3.0 V min

Power Supply Rejection Ratio PSRR V = + 2.7 V to +12 V 70 mV/V
Large Signal Voltage Gain A
Output Voltage High V
Output Voltage Low V
Supply Current/Amplifier I

NOTE
Electrical tests and wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed for
standard product dice. Consult factory to negotiate specifications based on dice lot qualifications through sample lot assembly and testing.

ABSOLUTE MAXIMUM RATINGS

1

VO

OH

OL

SY

RL = 2 kW 15 V/mV min
I

= 20 mA 4.975 V min

SOURCE

I

= 20 mA25 mV max

SINK

VO = 0 V, RL = • 600 mA max

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

Input Voltage . . . . . . . . . . . . . . . . . . . . . . . –V

– 0.2 V to +V

S

S

Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . ±30 V

Output Short Circuit Duration to GND . . . . . . . . . Indefinite

Storage Temperature Range

R-14, R-16 Packages . . . . . . . . . . . . . . . . –65∞C to +150∞C

Operating Temperature Range

AD824A . . . . . . . . . . . . . . . . . . . . . . . . . . . –40∞C to +85∞C

Junction Temperature Range

R-14, R-16 Packages . . . . . . . . . . . . . . . . –65∞C to +150∞C

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

Package Type q

2

JA

q

JC

Unit

14-Lead SOIC (R) 120 36 ∞C/W
16-Lead SOIC (R) 92 27 ∞C/W

NOTES

1

Absolute maximum ratings apply to packaged parts unless otherwise noted.

2

qJA is specified for the worst case conditions, i.e., q

for P-DIP packages; qJA is specified for device soldered in circuit board for SOIC
package.

ORDERING GUIDE

is specified for device in socket

JA

Figure 1. Simplified Schematic of 1/4 AD824

Temperature Package Package

Model Range Description Option

AD824AR-14 –40∞C to +85∞C 14-Pin SOIC R-14
AD824AR-14-3V –40∞C to +85∞C 14-Pin SOIC R-14

AD824AR-16 –40∞C to +85∞C 16-Pin SOIC R-16

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 AD824 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. C

–5–

WARNING!

ESD SENSITIVE DEVICE