Datasheet ADR827 Datasheet (ANALOG DEVICES)

Low Power, Precision Reference

G

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FEATURES

10-lead MSOP
400 μA supply current

−40°C to +125°C temperature range
On-board precision resistors
Reference

ADR821: 2.8 V to 15 V operation
ADR827: 2.7 V to 15 V operation
±0.2% initial accuracy
15 ppm/°C temperature drift maximum
+5 mA/−3 mA output drive

Amplifier

ADR821

±2.8 V to ±15 V operation

2.8 V to 15 V single-supply operation

ADR827

±2.7 V to ±15 V operation

2.7 V to 15 V single-supply operation
Rail-to-rail input and output
500 μV offset voltage maximum
50 nA bias current maximum
Unity gain stable
No phase reversal

and Op Amp

ADR821/ADR827

FUNCTIONAL BLOCK DIAGRAM

ADR821/ADR827

1

V+

R

2

1

3

4

5

NC = NO CONNECT

1

REF

Figure 1.

R

ND

NC

V–

Table 1. Selection Table

Reference

Part No.

V

OUT

ADR827ARMZ 1.25 V ±0.4% 30 ppm/°C
ADR827BRMZ 1.25 V ±0.2% 15 ppm/°C
ADR821ARMZ 2.50 V ±0.4% 30 ppm/°C
ADR821BRMZ 2.50 V ±0.2% 15 ppm/°C

10

R

2

9

8

7

6

Reference
Accuracy

AMP_OUT

R

2

–IN

+IN

REF_OUT

Reference
Temperature
Coefficient

06665-001

APPLICATIONS

Battery-powered instrumentation
Portable medical instrumentation
Data acquisition systems
Industrial process controls
Automotive applications

GENERAL DESCRIPTION

The ADR821/ADR827 combines a precision voltage reference
and an op amp in a 10-lead mini small outline package (MSOP).
The reference and the op amp can be operated independently,
offering the user a range of flexibility when arranging the
combination. Featuring a combined operating current of less
than 400 μA and 15 ppm/°C temperature drift on the reference,
the ADR821/ADR827 are ideally suited for applications requir­ing precision and low power.

Rev. 0

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
rights of third parties that may result from its use. Specifications subject to change without notice. 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.

Available with the reference at 1.25 V and at 2.5 V, the
ADR821/ADR827 also come in two grades. The reference on
the A grade offers 30 ppm/°C temperature drift performance
and ±0.4% initial accuracy. The B grade provides a tighter
temperature drift performance of 15 ppm/°C and only ±0.2%
initial accuracy. All versions operate from −40°C to +125°C.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2007 Analog Devices, Inc. All rights reserved.

ADR821/ADR827

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TABLE OF CONTENTS

Features.............................................................................................. 1

Absolute Maximum Ratings ............................................................9

Applications....................................................................................... 1

Functional Block Diagram .............................................................. 1

General Description ......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

ADR821 Electrical Characteristics—Reference ....................... 3

ADR821 Electrical Characteristics—Amplifier
(V

= ±2.8 V)................................................................................. 4

S

ADR821 Electrical Characteristics—Amplifier
(V

= ±15 V).................................................................................. 5

S

ADR827 Electrical Characteristics—Reference ....................... 6

ADR827 Electrical Characteristics—Amplifier
(V

= ±2.7 V)................................................................................. 7

S

ADR827 Electrical Characteristics—Amplifier
(V

= ±15 V).................................................................................. 8

S

REVISION HISTORY

Thermal Resistance.......................................................................9

ESD Caution...................................................................................9

Pin Configuration and Function Descriptions........................... 10

Typical Performance Characteristics........................................... 11

Reference ..................................................................................... 11

Amplifier (AD821/AD827)....................................................... 15

Applications Information.............................................................. 18

+2.5 V and −2.5 V Outputs (ADR821) ................................... 18

2.5 V and 5.0 V Outputs (ADR821)......................................... 18

Multiple 2.5 V Outputs (ADR821)........................................... 18

Outline Dimensions....................................................................... 19

Ordering Guide .......................................................................... 19

10/07—Revision 0: Initial Version

Rev. 0 | Page 2 of 20

ADR821/ADR827

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SPECIFICATIONS

ADR821 ELECTRICAL CHARACTERISTICS—REFERENCE

VIN = 2.8 V to 15 V, TA = 25°C, C

Table 2.

Parameter Symbol Conditions Min Typ Max Unit

OUTPUT VOLTAGE V

A Grade 2.490 2.500 2.510 V
B Grade 2.495 2.500 2.505 V

INITIAL ACCURACY V

A Grade 10 mV

0.40 %
B Grade 5.00 mV

0.20 %

TEMPERATURE COEFFICIENT TCV

A Grade 30 ppm/°C
B Grade 15 ppm/°C

DROPOUT (V

– VIN) VDO I

OUT

LINE REGULATION ∆V
LOAD REGULATION ∆V

I

I
VOLTAGE NOISE e
BROADBAND NOISE 10 Hz to 10 kHz 430 μV p-p
TURN-ON SETTLING TIME tR C
POWER SUPPLY

Positive Supply Current I
Negative Supply Current I

ON-BOARD RESISTORS R1, R2

Resistor Tolerance 8 10 12 kΩ
Resistor Matching 0.5 %
Resistor Temperature Coefficient TC ±100 ppm/°C

= C

IN

= 0.1 μF, unless otherwise noted.

OUT

OUT

OERR

−40°C < TA < +125°C

OUT

= 0 mA 0.3 V

OUT

/∆VIN VIN = 2.8 V to 15 V, −40°C < TA < +125°C 20 50 ppm/V

OUT

/∆I

= 0 mA to 5 mA, −40°C < TA < +125°C,

LOAD

I

LOAD

V

= 5 V

IN

= 0 mA to 5 mA, VIN = 5 V 80 200 ppm/mA

LOAD

= −3 mA to 0 mA, −40°C < TA < +125°C,

I

LOAD

V

= 5 V

IN

= −3 mA to +5 mA, VIN = 5 V 80 300 ppm/mA

LOAD

= 0 μF 80 μs

IN

OUT

0.1 Hz to 10 Hz 16 μV p-p

N p-p

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

400 ppm/mA

600 ppm/mA

Rev. 0 | Page 3 of 20

ADR821/ADR827

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ADR821 ELECTRICAL CHARACTERISTICS—AMPLIFIER (VS = ±2.8 V)

VCM = 0 V, TA = 25°C, unless otherwise noted.

Table 3.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Input Offset Voltage VOS −40°C < TA < +125°C 100 500 μV
Input Offset Voltage Drift TCVOS −40°C < TA < +125°C 2 5 μV/°C
Input Bias Current IB −40°C < TA < +125°C 15 50 nA
Input Offset Bias Current IOS −40°C < TA < +125°C 5 25 nA
Large Signal Voltage Gain AVO V
R
R
Common-Mode Rejection Ratio CMRR VCM = −1.5 V to +1.5 V, −40°C < TA < +125°C 75 100 dB
85 dB

OUTPUT CHARACTERISTICS

Output Voltage High VOH I
I
Output Voltage Low VOL I
I

POWER SUPPLY

Positive Supply Current I
Negative Supply Current I

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

Power Supply Rejection Ratio PSRR VS = ±2.8 V to ±15 V 75 100 dB

DYNAMIC PERFORMANCE

Slew Rate SR R
Gain Bandwidth Product GBP C
Phase Margin φM C

NOISE PERFORMANCE

Voltage Noise e

f = 0.1 Hz to 10 Hz 0.2 μV p-p

N p-p

Voltage Noise Density eN f = 1 kHz 16 nV/√Hz

= −1.5 V to +1.5 V

OUT

= 10 kΩ, −40°C < TA < +125°C 99 108 dB

LOAD

= 2 kΩ, −40°C < TA < +125°C 94 100 dB

LOAD

= 1 mA 2.6 2.7 V

LOAD

= 1 mA, −40°C < TA < +125°C 2.55 V

LOAD

= 1 mA −2.7 −2.6 V

LOAD

= 1 mA, −40°C < TA < +125°C −2.55 V

LOAD

= 10 kΩ, C

LOAD

= 14 pF 1.0 MHz

LOAD

= 14 pF 72.5 Degrees

LOAD

= 10 pF, AV = +1 0.5 V/μs

LOAD

Rev. 0 | Page 4 of 20

ADR821/ADR827

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ADR821 ELECTRICAL CHARACTERISTICS—AMPLIFIER (VS = ±15 V)

VCM= 0 V, TA = 25°C, unless otherwise noted.

Table 4.A

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Input Offset Voltage VOS −40°C < TA < +125°C 100 500 μV
Input Offset Voltage Drift TCVOS −40°C < TA < +125°C 2 5 μV/oC
Input Bias Current IB −40°C < TA < +125°C 10 50 nA
Input Offset Bias Current IOS −40°C < TA < +125°C 5 25 nA
Large Signal Voltage Gain AVO V
R
R
Common-Mode Rejection Ratio CMRR VCM = −14 V to +14 V, −40°C < TA < +125°C 75 100 dB
85 dB

OUTPUT CHARACTERISTICS

Output Voltage high VOH I
I
Output Voltage Low VOL I
I
Output Current ISC Short-circuit current ±20 mA

POWER SUPPLY

Positive Supply Current I
Negative Supply Current I

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

Power Supply Rejection Ratio PSRR VS = ±2.8 V to ±15 V 75 100 dB

DYNAMIC PERFORMANCE

Slew Rate SR R
Gain Bandwidth Product GBP C
Phase Margin φM C

NOISE PERFORMANCE

Voltage Noise e

f = 0.1 Hz to 10 Hz 0.2 μV p-p

N p-p

Voltage Noise Density eN f = 1 kHz 16 nV/√Hz

= −14 V to +14 V

OUT

= 10 kΩ, −40°C < TA < +125°C 109.5 118 dB

LOAD

= 2 kΩ, −40°C < TA < +125°C 100 111 dB

LOAD

= 1 mA 14.8 14.9 V

LOAD

= 1 mA, −40°C < TA < +125°C 14.75 V

LOAD

= 1 mA −14.9 −14.8 V

LOAD

= 1 mA, −40°C < TA < +125°C −14.75 V

LOAD

= 10 kΩ, C

LOAD

= 14 pF 1.0 MHz

LOAD

= 14 pF 75.4 Degrees

LOAD

= 10 pF, AV = +1 0.5 V/μs

LOAD

Rev. 0 | Page 5 of 20

ADR821/ADR827

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ADR827 ELECTRICAL CHARACTERISTICS—REFERENCE

VIN = 2.7 V to 15 V, TA = 25°C, C

Table 5.

Parameter Symbol Conditions Min Typ Max Unit

OUTPUT VOLTAGE V

A Grade
B Grade 1.2475 1.250 1.2525 V

INITIAL ACCURACY V

A Grade

0.40 %
B Grade 2.50 mV

0.20 %

TEMPERATURE COEFFICIENT TCV

A Grade 30 ppm/°C
B Grade 15 ppm/°C

DROPOUT (V

– VIN) V

OUT

LINE REGULATION ∆V
LOAD REGULATION ∆V

I

I
VOLTAGE NOISE e
BROADBAND NOISE 10 Hz to 10 kHz 260 μV p-p
TURN-ON SETTLING TIME tR C
POWER SUPPLY

Positive Supply Current I
Negative Supply Current I

ON-BOARD RESISTORS R1, R2

Resistor Tolerance 8 10 12 kΩ
Resistor Matching 0.5 %
Resistor Temperature Coefficient TC ±100 ppm/°C

= C

IN

= 0.1 μF, unless otherwise noted.

OUT

OUT

OERR

OUT

DO

/∆VIN VIN = 2.7 V to 15 V, −40°C < TA < +125°C 20 50 ppm/V

OUT

/∆I

OUT

0.1 Hz to 10 Hz 8 μV p-p

N p-p

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

1.245 1.250 1.255 V

5 mV

−40°C < TA < +125°C

I

= 0 mA 1.45 V

OUT

LOAD

= 0 mA to 5 mA, −40°C < TA < +125°C,

I

LOAD

V

= 3 V

IN

= 0 mA to 5 mA, VIN = 3 V 80 200 ppm/mA

LOAD

= −3 mA to 0 mA, −40°C < TA < +125°C,

I

LOAD

V

= 3 V

IN

= −3 mA to +5 mA, VIN = 3 V 80 300 ppm/mA

LOAD

= 0 μF, C

IN

= 0.1 μF 80 μs

OUT

400 ppm/mA

600 ppm/mA

Rev. 0 | Page 6 of 20

ADR821/ADR827

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ADR827 ELECTRICAL CHARACTERISTICS—AMPLIFIER (VS = ±2.7 V)

VCM = 0 V, TA = 25°C, unless otherwise noted.

Table 6.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Input Offset Voltage VOS −40°C < TA < +125°C 100 500 μV
Input Offset Voltage Drift TCVOS −40°C < TA < +125°C 2 5 μV/°C
Input Bias Current IB −40°C < TA < +125°C 15 50 nA
Input Offset Bias Current IOS −40°C < TA < +125°C 5 25 nA

Large Signal Voltage Gain AVO V
R
R

Common-Mode Rejection Ratio CMRR VCM = −1.5 V to +1.5 V, −40°C < TA < +125°C 75 100 dB

85 dB

OUTPUT CHARACTERISTICS

Output Voltage High VOH I

I

Output Voltage Low VOL I

I

POWER SUPPLY

Positive Supply Current I

Negative Supply Current I

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

Power Supply Rejection Ratio PSRR VS = ±2.7 V to ±15 V 75 100 dB

DYNAMIC PERFORMANCE

Slew Rate SR R

Gain Bandwidth Product GBP C

Phase Margin φM C

NOISE PERFORMANCE

Voltage Noise e

f = 0.1 Hz to 10 Hz 0.2 μV p-p

N p-p

Voltage Noise Density eN f = 1 kHz 16 nV/√Hz

= −1.5 V to +1.5 V

OUT

= 10 kΩ, −40°C < TA < +125°C 99 108 dB

LOAD

= 2 kΩ, −40°C < TA < +125°C 94 100 dB

LOAD

= 1 mA 2.5 2.6 V

LOAD

= 1 mA, −40°C < TA < +125°C 2.45 V

LOAD

= 1 mA −2.6 −2.5 V

LOAD

= 1 mA, −40°C < TA < +125°C −2.45 V

LOAD

= 10 kΩ, C

LOAD

= 14 pF 1.0 MHz

LOAD

= 14 pF 71.3 Degrees

LOAD

= 10 pF, AV = +1 0.5 V/μs

LOAD

Rev. 0 | Page 7 of 20

ADR821/ADR827

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ADR827 ELECTRICAL CHARACTERISTICS—AMPLIFIER (VS = ±15 V)

VCM = 0 V, TA = 25°C, unless otherwise noted.

Table 7.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Input Offset Voltage VOS −40°C < TA < +125°C 100 500 μV
Input Offset Voltage Drift TCVOS −40°C < TA < +125°C 2 5 μV/°C
Input Bias Current IB −40°C < TA < +125°C 10 50 nA
Input Offset Bias Current IOS −40°C < TA < +125°C 5 25 nA
Large Signal Voltage Gain AVO V
R
R
Common-Mode Rejection Ratio CMRR VCM = −14 V to +14 V, −40°C < TA < 125°C 75 100 dB
85 dB

OUTPUT CHARACTERISTICS

Output Voltage High VOH I
I
Output Voltage Low VOL I
I
Output Current ISC Short-circuit current ±20 mA

POWER SUPPLY

Positive Supply Current I
Negative Supply Current I

No load, −40°C < TA < +125°C 400 μA

SY+

No load, −40°C < TA < +125°C 300 μA

SY−

Power Supply Rejection Ratio PSRR VS = ±2.7 V to ±15 V 75 100 dB

DYNAMIC PERFORMANCE

Slew Rate SR R
Gain Bandwidth Product GBP C
Phase Margin φM C

NOISE PERFORMANCE

Voltage Noise e

f = 0.1 Hz to 10 Hz 0.2 μV p-p

N p-p

Voltage Noise Density eN f = 1 kHz 16 nV/√Hz

= −14 V to +14 V

OUT

= 10 kΩ, −40°C < TA < +125°C 109.5 118 dB

LOAD

= 2 kΩ, −40°C < TA < +125°C 100 111 dB

LOAD

= 1 mA 14.8 14.9 V

LOAD

= 1 mA, −40°C < TA < +125°C 14.75 V

LOAD

= 1 mA −14.9 −14.8 V

LOAD

= 1 mA, −40°C < TA < +125°C −14.75 V

LOAD

= 10 kΩ, C

LOAD

= 14 pF 1.0 MHz

LOAD

= 14 pF 75.4 Degrees

LOAD

= 10 pF, AV = +1 0.5 V/μs

LOAD

Rev. 0 | Page 8 of 20

ADR821/ADR827

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ABSOLUTE MAXIMUM RATINGS

TA= 25°C, unless otherwise noted.

Table 8.

Parameter Rating

Supply Voltage ±18 V
Output Short-Circuit Duration to GND Indefinite
Storage Temperature Range –65°C to +125°C
Operating Temperature Range –40°C to +125°C
Junction Temperature Range –65°C to +125°C
Lead Temperature (Soldering, 60 sec) 300°C

Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, θJA is

specified for device soldered in circuit board for surface-mount
packages.

Table 9. Thermal Resistance

Package Type θJA θ

10-Lead MSOP (RM-10) 172 50 °C/W

Unit

JC

ESD CAUTION

Rev. 0 | Page 9 of 20

ADR821/ADR827

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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

V+

1

R

2

1

ADR821/

3

ND

ADR827

TOP VIEW

4

NC

(Not to Scale)

V–

5

NC = NO CONNECT

Figure 2. Pin Configuration

Table 10. Pin Function Descriptions

Pin No. Mnemonic Description

1 V+ Input Voltage of the Reference/Positive Supply of the Amplifier
2 R1 Resistance Tied to Positive Input of the Amplifier
3 GND Ground
4 NC Do Not Connect Any External Components to This Pin
5 V− Negative Supply of the Amplifier
6 REF_OUT Output Voltage of the Reference
7 +IN Positive Input of the Amplifier
8 −IN Negative Input of the Amplifier
9 R2 Resistance Tied to Positive Input of the Amplifier
10 AMP_OUT Output Pin of the Amplifier

AMP_OUT

10

R

9

8

–IN

7

+IN

REF_OUT

6

2

6665-002

Rev. 0 | Page 10 of 20

ADR821/ADR827

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TYPICAL PERFORMANCE CHARACTERISTICS

REFERENCE

2.512
CIN = 0.1µF

= 0.1µF

C

OUT

V

= 15V

IN

2.508

2.504

(V)

2.500

OUT

V

2.496

2.492

2.488

–40 125

–25 –10 5 20 35 50 65 80 95 110

TEMPERATURE (° C)

Figure 3. ADR821 V

vs. Temperature

OUT

06665-005

1.260
CIN = 0.1µF

= 0.1µF

C

OUT

1.258

= 15V

V

IN

1.256

1.254

1.252

(V)

1.250

OUT

V

1.248

1.246

1.244

1.242

1.240

–40 125

–25–105 203550658095110

TEMPERATURE (° C)

Figure 6. ADR827 V

vs. Temperature

OUT

06665-008

4

3

2

1

0

LINE REGULATION (ppm/V)

–1

–2

–40 –25 –10 5 20 35 50 65 80 95 110

TEMPERATURE (° C)

Figure 4. ADR821 Line Regulation vs. Temperature

0.40

0.35

0.30

0.25

(mA)

SY+

0.20

I

0.15

0.10

+125°C

+25°C

–40°C

CIN = 0.1µF

= 0.1µF

C

OUT

V

= 15V

IN

CIN = 0.1µF

= 0.1µF

C

OUT

125

14

12

10

8

6

4

LINE REGULATION (ppm/V)

2

0

–40 –25 –10 5 20 35 50 65 80 95 110

06665-006

TEMPERATURE (° C)

CIN = 0.1µF

= 0.1µF

C

OUT

= 15V

V

IN

125

06665-009

Figure 7. ADR827 Line Regulation vs. Temperature

0.40
CIN = 0.1µF

= 0.1µF

C

OUT

0.35

0.30

0.25

(mA)

0.20

SY+

I

0.15

0.10

0.05

+125°C

+25°C

–40°C

0.05

2.5 15.0

5.0 7.5 10.0 12.5

SUPPLY VOLTAGE (±V)

06665-007

Figure 5. ADR821 Supply Current (+) vs. Supply Voltage

Rev. 0 | Page 11 of 20

0

2.5 15.0

5.0 7.5 10.0 12.5

SUPPLY VOLTAGE (±V)

Figure 8. ADR827 Supply Current (+) vs. Supply Voltage

06665-010

ADR821/ADR827

www.BDTIC.com/ADI

0.25

0.20

CIN = 0.1µF

= 0.1µF

C

OUT

+125°C

0.25

0.20

CIN = 0.1µF

= 0.1µF

C

OUT

+125°C

0.15

(mA)

SY–

I

0.10

0.05

0

2.5 15.0

5.0 7.5 10.0 12.5

+25°C

–40°C

SUPPLY VOLTAGE (±V)

Figure 9. ADR821 Supply Current (−) vs. Supply Voltage

1.2
CIN = 0.1µF

= 0.1µF

C

OUT

1.0

0.8

0.6

DROPOUT (V)

0.4

0.2

0

–3 7

–2–10123456

LOAD CURRENT (mA)

+125°C

+25°C

–40°C

Figure 10. ADR821 Dropout vs. Load Current

0.15

(mA)

SY–

I

0.10

0.05

0

2.5 15.0

06665-011

5.0 7.5 10.0 12.5

+25°C

–40°C

SUPPLY VOLTAGE (±V)

06665-014

Figure 12. ADR827 Supply Current (−) vs. Supply Voltage

2.0
CIN = 0.1µF

= 0.1µF

C

OUT

1.8

1.6

1.4

1.2

1.0

0.8

DROPOUT (V)

0.6

0.4

0.2

0

–3 7

06665-012

–40°C

+25°C

+125°C

–2 –1 0 1 2 3 4 5 6

LOAD CURRENT (mA)

06665-015

Figure 13. ADR827 Dropout vs. Load Current

50

I

= 3mA

SINK

C

= C

= 0.1µF

IN

45

40

35

30

25

20

15

LOAD REGULATION (ppm/mA)

10

5

OUT

VS = 5V

VS = 15V

–40 –25 –10 5 20 35 50 65 80 95 110 125

TEMPERATURE (° C)

Figure 11. ADR821 Load Regulation vs. Temperature

06665-013

Rev. 0 | Page 12 of 20

80

I

= 3mA

SINK

C

= C

= 0.1µF

IN

OUT

70

60

50

LOAD REGULATION (ppm/mA)

40

30

–40 –25 –10 5 20 35 50 65 80 95 110 125

VS = 15V

VS = 3V

TEMPERATURE (° C)

Figure 14. ADR827 Load Regulation vs. Temperature

06665-016

ADR821/ADR827

www.BDTIC.com/ADI

0

I

= 5mA

SOURCE

= C

C

–20

–40

–60

–80

–100

LOAD REGULATION (ppm/mA)

–120

–140

–40 125

= 0.1µF

IN

OUT

VS = 5V

VS = 15V

–25 –10 5 20 35 50 65 80 95 110

TEMPERATURE (° C)

Figure 15. ADR821 Load Regulation vs. Temperature

10µV/DIV

1

CIN = C

15.6µV p-p

2.78µV rms

OUT

= 0.1µF

06665-017

0

I

= 5mA

SOURCE

C

= C

= 0.1µF

IN

–20

–40

–60

–80

–100

LOAD REGULATION (ppm/mA)

–120

–140

OUT

VS = 3V

VS = 15V

–40 125

–25 –10 5 20 35 50 65 80 95 110

TEMPERATURE (° C)

Figure 18. ADR827 Load Regulation vs. Temperature

5µV/DIV

1

CIN = C

8.3µV p-p

1.33µV rms

OUT

= 0.1µF

06665-020

100µV/DIV

TIME (1s/ DIV)

Figure 16. ADR821 0.1 Hz to 10 Hz Noise

1

CIN = C
426µV p-p

55.6µV rms

OUT

= 0.1µF

TIME (1s/ DIV)

Figure 17. ADR821 10 Hz to 10 kHz Noise

06665-018

TIME (1s/ DIV)

06665-021

Figure 19. ADR827 0.1 Hz to 10 Hz Noise

CIN = C
258µV p-p

34.6µV rms

1

100µV/DIV

06665-019

OUT

= 0.1µF

TIME (1s/ DIV)

06665-022

Figure 20. ADR827 10 Hz to 10 kHz Noise

Rev. 0 | Page 13 of 20

ADR821/ADR827

www.BDTIC.com/ADI

CHANNEL 2:
V

= 1V/DIV

OUT

2

CHANNEL 1:
V

= 2V/DIV

IN

C

= 0µF

IN

C

1

= 0.1µF

L

TIME = 20µ s/DIV

6665-023

Figure 21. ADR821 Turn-On Response

2

1

Figure 22. ADR827 Turn-On Response

CHANNEL 2:
V

= 500mV/DIV

OUT

CHANNEL 1:
V

= 2V/DIV

IN

C

= 0µF

IN

C

= 0.1µF

L

TIME = 20µ s/DIV

6665-024

Rev. 0 | Page 14 of 20

ADR821/ADR827

www.BDTIC.com/ADI

AMPLIFIER (AD821/AD827)

120

VSY = ±15V
T

= 25°C

A

100

80

60

40

NUMBER OF SAMPLES

20

0

–500 –400 –300 –200 –100 0 100 200 300 400 500

V

(µV)

OS

Figure 23. Input Offset Voltage Distribution

06665-025

500

VSY = ±15V
T

= 25°C

A

400

300

200

100

(µV)

0

OS

V

–100

–200

–300

–400

–500

–15 15

–12–9–6–3036912

V

(V)

CM

Figure 26. Input Offset Voltage vs. Common-Mode Voltage

06665-029

160

VSY = ±15V

140

120

100

80

60

NUMBER OF SAMPLE S

40

20

0

–5 –4 –3 –2 –1 0 1 2 3 4 5

(µV/°C)

TCV

OS

Figure 24. Offset Voltage Drift Distribution

60

VSY = ±15V

50

= 25°C

T

A

40

30

20

10

(nA)

B

I

0

–10

–20

–30

–40

–13 –11 –9 –7 –5 –3 –1 1 3 5 7 9 11 13

V

(V)

CM

Figure 25. Input Bias Current vs. Common-Mode Voltage

200

100

(µV)

0

OS

V

–100

–200

–55 155

–40 –25 –10 5 20 35 50 65 80 95 110 125 140

06665-026

TEMPERATURE (° C)

VSY = ±15V

06665-027

Figure 27. Input Offset Voltage vs. Temperature

100000

VSY = ±15V

= 25°C

T

A

10000

1000

VOL SINKING

100

10

1

OUTPUT SWING SATURATION VOLTAGE (mV)

0.1

0.01 100

06665-030

VSY – VOH SOURCING

0.1 1 10

LOAD CURRENT (mA)

06665-028

Figure 28. Output Swing Saturation Voltage vs. Load Current

Rev. 0 | Page 15 of 20

ADR821/ADR827

V

www.BDTIC.com/ADI

70

50

30

10

GAIN (dB)

–10

–30

–50

100 100M

1k 10k 100k 1M 10M

PHASE

GAIN

FREQUENCY (Hz)

VSY = ±15V
T

A

Figure 29. Open-Loop Gain and Phase vs. Frequency

= 25°C

120

105

90

75

60

45

30

15

0

–15

–30

–45

–60

PHASE (Degrees)

06665-031

140

120

100

80

60

CMRR (dB)

40

20

0

100 100M

1k 10k 100k 1M 10M

FREQUENCY (Hz)

VSY = ±15V
T

= 25°C

A

Figure 32. CMRR vs. Frequency

06665-034

50

G = 100

40

30

G = 10

20

10

G = 1

0

(dB)

CL

–10

A

–20

–30

–40

–50

–60

100 100M

1k 10k 100k 1M 10M

FREQUENCY (Hz)

VSY = ±15V
T

A

Figure 30. Closed-Loop Gain vs. Frequency

1200

VSY = ±15V

= 25°C

T

A

1000

800

()

600

OUT

Z

400

= 25°C

140

120

100

80

60

PSRR (dB)

40

20

0

100 100M

06665-032

1k 10k 100k 1M 10M

FREQUENCY (Hz)

PSRR–

VSY = ±15V

= 25°C

T

A

PSRR+

06665-035

Figure 33. PSRR vs. Frequency

R

= 10k

LOAD

C

= 10pF

LOAD

V

= ±15V

SY

2

= 2V/DI

OUT

V

200

G = 100 G = 10 G = 1

0

10 10M

100 1k 10k 100k 1M

FREQUENCY (Hz)

Figure 31. Z

vs. Frequency

OUT

06665-033

Rev. 0 | Page 16 of 20

TIME = 10µs/DIV

Figure 34. Large Signal Transient Response

06665-036

ADR821/ADR827

V

V

www.BDTIC.com/ADI

RL = 10k
C

= 10pF

L

V

= ±15V

SY

2

= 50mV/DI

OUT

V

TIME = 1µs/DIV

Figure 35. Small Signal Transient Response, C

= 10 pF

L

1000

100

EN (nV/ Hz)

10

1

06665-037

1 10000

10 100 1000

FREQUENCY (Hz)

Figure 37. Voltage Noise Density

VSY = ±15V
T

= 25°C

A

06665-039

RL = 10k
C

= 100pF

V

L

= ±15V

SY

2

= 50mV/DI

OUT

V

TIME = 1µs/DIV

Figure 36. Small Signal Transient Response, C

= 100 pF

L

06665-038

Rev. 0 | Page 17 of 20

ADR821/ADR827

www.BDTIC.com/ADI

APPLICATIONS INFORMATION

+2.5 V AND −2.5 V OUTPUTS (ADR821)

REF_OUT

REF

V+

+IN

R

1

Figure 38. +2.5 V and −2.5 V Outputs

V–

10k10k

AMP_OUT

R

In many dual-supply applications, it is desirable to have ±2.5 V
references. Using the configuration shown in Figure 38, it is
possible to generate −2.5 V with the help of a +2.5 V reference,
an internal op amp, and 10 kΩ resistors. The supply voltages V+
and V− should be greater than +2.8 V and −2.8 V, respectively.
The op amp is configured as an inverting amplifier with a gain
of −1, which produces −2.5 V at the output of the op amp. The
output of the reference is fed to the amplifier inverting input.
Because the op amp has very low input offset voltage (500 μV
over the full temperature range) and the TC ratio of the
resistors is typically ±25 ppm/°C, the −2.5 V output is less than
7 mV away from the theoretical value.

0.1µF

2

+2.5V

–2.5V

6665-003

2.5 V AND 5.0 V OUTPUTS (ADR821)

REF_OUT

REF

V+

+IN

R

1

Figure 39. 2.5 V and 5.0 V Outputs

V–

–IN

10k10k

AMP_OUT

R

In many single-supply applications, it is desirable to have
multiple reference voltages. Using the configuration shown in
Figure 39, it is possible to generate 5.0 V with the help of a

2.5 V reference, an internal op amp, and resistors. V+ should
be kept at greater than 5.8 V and V− can be connected either
to ground or to negative supply. The output of the reference is

0.1µF

2

2.5V

5.0V

06665-004

fed to the amplifier noninverting input. The op amp is config­ured as a noninverting amplifier with a gain of +2, which
produces 5 V at the output of the op amp. Using the guaranteed
maximum offset voltage over the temperature, and the typical
TC ratio of the resistors over the full temperature range, the
output is within 15 mV of the calculated value.

MULTIPLE 2.5 V OUTPUTS (ADR821)

REF_OUT

REF

V+

+IN

R

1

Figure 40. Multiple 2.5 V Outputs

V–

–IN

AMP_OUT

10k10k

On some boards, sensitive analog circuits, such as a VCO, exist
with noisy digital circuits. If the supply current requirements
are low (less than 3 mA), series references and op amps can be
used. Using the configuration shown in Figure 40, two different

2.5 V supplies can be created using a single ADR821. The supply
voltage V+ should be greater than 2.8 V and V− can be con­nected to ground or a negative voltage. The op amp is configured
as a voltage follower with a gain of +1, which produces 2.5 V at
the output of the op amp. The output of the reference is fed
to the amplifier noninverting input. Because the op amp has
very low input offset voltage (500 μV maximum over the full
temperature range), the output voltage from the op amp section
tracks the reference voltage within 1 mV. For a dynamic load,
such as the reference input pin on some analog-to-digital
converters, the load should be connected to an op amp output
and the noise sensitive circuitry, such as a VCO, should be
connected to the reference output. If the dynamic load is con­nected to the reference voltage, any perturbations appear as a
signal to the input of the voltage follower and appear on the
other output.

0.1µF

2.5V

2.5V

R

2

06665-040

Rev. 0 | Page 18 of 20

ADR821/ADR827

www.BDTIC.com/ADI

OUTLINE DIMENSIONS

3.10

3.00

2.90

6

10

3.10

3.00

2.90

1

PIN 1

0.50 BSC

0.95

0.85

0.75

0.15

0.05

0.33

0.17

COPLANARITY

0.10

COMPLIANT TO JEDEC STANDARDS MO-187-BA

Figure 41. 10-Lead Mini Small Outline Package [MSOP]

ORDERING GUIDE

Output

Models

Range

ADR821ARMZ-REEL71 −40°C to +125°C 2.500 10.00 ±0.40 30 10-Lead MSOP RM-10 1,000 R2G
ADR821ARMZ-R21 −40°C to +125°C 2.500 10.00 ±0.40 30 10-Lead MSOP RM-10 250 R2G
ADR821BRMZ-REEL71 −40°C to +125°C 2.500 5.00 ±0.20 15 10-Lead MSOP RM-10 1,000 R2H
ADR821BRMZ-R21 −40°C to +125°C 2.500 5.00 ±0.20 15 10-Lead MSOP RM-10 250 R2H
ADR827ARMZ-REEL71 −40°C to +125°C 1.250 5.00 ±0.40 30 10-Lead MSOP RM-10 1,000 R0Z
ADR827ARMZ-R21 −40°C to +125°C 1.250 5.00 ±0.40 30 10-Lead MSOP RM-10 250 R0Z
ADR827BRMZ-REEL71 −40°C to +125°C 1.250 2.50 ±0.20 15 10-Lead MSOP RM-10 1,000 R2B

Temperature

ADR827BRMZ-R2

1

Z = RoHS Compliant Part.

1

−40°C to +125°C 1.250 2.50 ±0.20 15 10-Lead MSOP RM-10 250 R2B

Voltage
(V

)

OUT

(mV) (%)

5.15

4.90

4.65

5

1.10 MAX

SEATING
PLANE

0.23

0.08

(RM-10)

Dimensions shown in millimeters

Initial

Accuracy

Temperature
Coefficient
(ppm/°C)

8°
0°

0.80

0.60

0.40

Package
Description

Package
Option

Ordering
Quantity Branding

Rev. 0 | Page 19 of 20

ADR821/ADR827

www.BDTIC.com/ADI

NOTES

©2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D06665-0-10/07(0)

Rev. 0 | Page 20 of 20