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REF194ES-REEL中文资料

Precision Micropower, Low Dropout

Voltage References

REF19x Series Rev. I

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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. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. T rademarks 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: 781.329.4700 https://www.wendangku.net/doc/cd1638891.html, Fax: 781.461.3113 ?2006 Analog Devices, Inc. All rights reserved.

FEATURES

Initial accuracy: ±2 mV maximum

Temperature coefficient: 5 ppm/°C maximum

Low supply current: 45 μA maximum

Sleep mode: 15 μA maximum

Low dropout voltage

Load regulation: 4 ppm/mA

Line regulation: 4 ppm/V

High output current: 30 mA

Short-circuit protection

APPLICATIONS

Portable instruments

ADCs and DACs

Smart sensors

Solar-powered applications

Loop current-powered instruments

GENERAL DESCRIPTION

The REF19x series precision band gap voltage references use a patented temperature drift curvature correction circuit and laser trimming of highly stable, thin-film resistors to achieve a very low temperature coefficient and high initial accuracy. The REF19x series is made up of micropower, low dropout voltage (LDV) devices, providing stable output voltage from supplies as low as 100 mV above the output voltage and consuming less than 45 μA of supply current. In sleep mode, which is enabled by applying a low TTL or CMOS level to the SLEEP pin, the output is turned off, and supply current is further reduced to less than 15 μA.

The REF19x series references are specified over the extended industrial temperature range (?40°C to +85°C), with typical performance specifications over ?40°C to +125°C for applications such as automotive.

All electrical grades are available in an 8-lead SOIC_N package; the PDIP and TSSOP packages are available only in the lowest electrical grade. Products are also available in die form. TEST PINS

Test Pin 1 and Test Pin 5 are reserved for in-package Zener zap. To achieve the highest level of accuracy at the output, the Zener zapping technique is used to trim the output voltage. Since each unit may require a different amount of adjustment, the resistance value at the test pins varies widely from pin to pin and from part to part. The user should leave Pin 1 and Pin 5 unconnected.

NOTES

1. NC = NO CONNECT.

2. TP PINS ARE FACTORY TEST

POINTS, NO USER CONNECTION.

Figure 1. 8-Lead SOIC_N and TSSOP Pin Configuration

(S Suffix and RU Suffix)

V S

SLEEP

GND

OUTPUT

NOTES

1. NC = NO CONNECT.

2. TP PINS ARE FACTORY TEST

POINTS, NO USER CONNECTION.

Figure 2. 8-Lead PDIP Pin Configuration

(P Suffix)

Table 1. Nominal Output Voltage

Part Number Nominal Output Voltage (V)

REF191 2.048

REF192 2.50

REF193 3.00

REF194 4.50

REF195 5.00

REF196 3.30

REF198 4.096

REF19x Series

Rev. I | Page 2 of 28

TABLE OF CONTENTS

Specifications.....................................................................................3 Electrical Characteristics—REF191 @ T A = 25°C....................3 Electrical Characteristics—REF191 @ ?40°C ≤ T A ≤ +85°C..4 Electrical Characteristics—REF191 @ ?40°C ≤ T A ≤+125°C.5 Electrical Characteristics—REF192 @ T A = 25°C....................5 Electrical Characteristics—REF192 @ ?40°C ≤ T A ≤ +85°C..6 Electrical Characteristics—REF192 @ ?40°C ≤ T A ≤ +125°C 6 Electrical Characteristics—REF193 @ T A = 25°C....................7 Electrical Characteristics—REF193 @ ?40°C ≤ T A ≤ +85°C..7 Electrical Characteristics—REF193 @ T A ≤ ?40°C ≤ +125°C 8 Electrical Characteristics—REF194 @ T a = 25°C.....................8 Electrical Characteristics—REF194 @ ?40°C ≤ T A ≤ +85°C..9 Electrical Characteristics—REF194 @ ?40°C ≤ T A ≤ +125°C 9 Electrical Characteristics—REF195 @ T A = 25°C..................10 Electrical Characteristics—REF195 @ ?40°C ≤ T A ≤ +85°C 10 Electrical Characteristics—REF195 @ ?40°C ≤ T A ≤ +125°C .......................................................................................................11 Electrical Characteristics—REF196 @ T A = 25°C..................11 Electrical Characteristics—REF196 @ ?40°C ≤ T A ≤ +85°C 12 Electrical Characteristics—REF196 @ ?40°C ≤ T A ≤ +125°C .......................................................................................................12 Electrical Characteristics—REF198 @ T A = 25°C..................13 Electrical Characteristics—REF198 @ ?40°C ≤ T A ≤ +85°C 13 Electrical Characteristics—REF198 @ ?40°C ≤ T A ≤ +125°C . (14)

Wafer Test Limits........................................................................14 Absolute Maximum Ratings.........................................................15 Thermal Resistance....................................................................15 ESD Caution................................................................................15 Typical Performance Characteristics...........................................16 Applications.....................................................................................19 Output Short-Circuit Behavior................................................19 Device Power Dissipation Considerations..............................19 Output Voltage Bypassing.........................................................19 Sleep Mode Operation...............................................................19 Basic Voltage Reference Connections.....................................19 Membrane Switch-Controlled Power Supply.........................19 Current-Boosted References with Current Limiting.............20 Negative Precision Reference without Precision Resistors...20 Stacking Reference ICs for Arbitrary Outputs.......................21 Precision Current Source..........................................................21 Switched Output 5 V/3.3 V Reference.....................................22 Kelvin Connections....................................................................22 Fail-Safe 5 V Reference..............................................................23 Low Power, Strain Gage Circuit...............................................24 Outline Dimensions.......................................................................25 Ordering Guide.. (26)

REVISION HISTORY

9/06—Rev. H to Rev. I

Updated Format..................................................................Universal Changes to Table 25 .......................................................................15 Changes to Figure 6........................................................................16 Changes to Figure 10, Figure 12, Figure 14, and Figure 16.......17 Changes to Figure 18......................................................................18 Changes to Figure 20......................................................................19 Changes to Figure 23......................................................................20 Changes to Figure 25......................................................................21 Updated Outline Dimensions.......................................................25 Changes to Ordering Guide..........................................................26 6/05—Rev. G to Rev. H

Updated Format..................................................................Universal Changes to Caption in Figure 7....................................................16 Updated Outline Dimensions.......................................................25 Changes to Ordering Guide. (26)

7/04—Rev. F to Rev. G

Changes to Ordering Guide.............................................................4 3/04—Rev. E to Rev. F

Updated Absolute Maximum Rating..............................................4 Changes to Ordering Guide..........................................................14 Updated Outline Dimensions.......................................................24 1/03—Rev. D to Rev. E

Changes to Figure 3 and Figure 4.................................................15 Changes to Output Short Circuit Behavior.................................17 Changes to Figure 20......................................................................17 Changes to Figure 24......................................................................19 Updated Outline Dimensions.......................................................23 1/96—Revision 0: Initial Version

REF19x Series

Rev. I | Page 3 of 28

SPECIFICATIONS

ELECTRICAL CHARACTERISTICS—REF191 @ T A = 25°C

@ V S = 3.3 V , T A = 25°C, unless otherwise noted. Table 2.

Parameter Mnemonic Condition Min Typ Max Unit INITIAL ACCURACY 1 E Grade V O I OUT = 0 mA 2.046 2.048 2.050 V F Grade 2.043 2.053 V G Grade

2.038 2.058 V LINE REGULATION 2

E Grade ΔV O /ΔV IN 3.0 V ≤ V S ≤ 15 V, I OUT = 0 mA 2 4 ppm/V

F and

G Grades

4 8 ppm/V LOAD REGULATION 2

E Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 30 mA 4 10 ppm/mA

F and

G Grades 6 15 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.15 V, I LOAD = 2 mA 0.95 V V S = 3.3 V, I LOAD = 10 mA 1.25 V V S = 3.6 V, I LOAD = 30 mA

1.55 V LONG-TERM STABILITY 3

DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz

20 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

REF19x Series

ELECTRICAL CHARACTERISTICS—REF191 @ ?40°C ≤ T A ≤ +85°C

@ V S = 3.3 V, ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

2 TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX? V MIN)/V O(T MAX? T MIN)

3 Guaranteed by characterization.

4 Line and load regulation specifications include the effect of self-heating.

Rev. I | Page 4 of 28

REF19x Series

Rev. I | Page 5 of 28

ELECTRICAL CHARACTERISTICS—REF191 @ ?40°C ≤ T A ≤+125°C

@ V S = 3.3 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted. Table 4.

Parameter Mnemonic Condition Min Typ Max Unit TEMPERATURE COEFFICIENT 1, 2 E Grade TCV O /°C I OUT = 0 mA 2 ppm/°C F Grade 5 ppm/°C G Grade 3 10 ppm/°C

LINE REGULATION 4

E Grade ΔV O /ΔV IN 3.0 V ≤ V S ≤ 15 V, I OUT = 0 mA 10 ppm/V

F and

G Grades 20 ppm/V

LOAD REGULATION 4

E Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 20 mA 10 ppm/mA

F and

G Grades 20 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.3 V, I LOAD = 10 mA 1.25 V V S = 3.6 V, I LOAD = 20 mA 1.55 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF192 @ T A = 25°C

@ V S = 3.3 V , T A = 25°C, unless otherwise noted. Table 5.

Parameter Mnemonic Condition

Min Typ Max Unit INITIAL ACCURACY 1

E Grade V O I OUT = 0 mA 2.498 2.500 2.502 V

F Grade 2.495 2.505 V

G Grade 2.490 2.510 V

LINE REGULATION 2

E Grade ΔV O /ΔV IN 3.0 V ≤ V S ≤ 15 V, I OUT = 0 mA 2 4 ppm/V

F and

G Grades 4 8 ppm/V LOAD REGULATION 2 E Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 30 mA 4 10 ppm/mA F and G Grades 6 15 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.5 V, I LOAD = 10 mA 1.00 V V S = 3.9 V, I LOAD = 30 mA 1.40 V LONG-TERM STABILITY 3DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz

25 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

REF19x Series

Rev. I | Page 6 of 28

ELECTRICAL CHARACTERISTICS—REF192 @ ?40°C ≤ T A ≤ +85°C

@ V S = 3.3 V , ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF192 @ ?40°C ≤ T A ≤ +125°C

@ V S = 3.3 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted.

Table 7.

Parameter Mnemonic Condition Min Typ Max Unit TEMPERATURE COEFFICIENT 1, 2 E Grade TCV O /°C I OUT = 0 mA 2 ppm/°C F Grade

5 ppm/°C G Grade 3

10 ppm/°C LINE REGULATION 4

E Grade ΔV O /ΔV IN 3.0 V ≤ V S ≤ 15 V, I OUT = 0 mA 10 ppm/V

F and

G Grades

20 ppm/V LOAD REGULATION 4

E Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 20 mA 10 ppm/mA

F and

G Grades 20 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.5 V, I LOAD = 10 mA 1.00 V V S = 4.0 V, I LOAD = 20 mA

1.50 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 7 of 28

ELECTRICAL CHARACTERISTICS—REF193 @ T A = 25°C

@ V S = 3.3 V , T A = 25°C, unless otherwise noted. Table 8.

Parameter Mnemonic Condition

Min Typ Max Unit INITIAL ACCURACY 1

G Grade V O I OUT = 0 mA 2.990 3.0 3.010 V LINE REGULATION 2 G Grade ΔV O /ΔV IN 3.3 V, ≤ V S ≤ 15 V, I OUT = 0 mA 4 8 ppm/V LOAD REGULATION 2 G Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 30 mA 6 15 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.8 V, I LOAD = 10 mA 0.80 V V S = 4.0 V, I LOAD = 30 mA 1.00 V LONG-TERM STABILITY 3DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz

30 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

ELECTRICAL CHARACTERISTICS—REF193 @ ?40°C ≤ T A ≤ +85°C

@ V S = 3.3 V , ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 8 of 28

ELECTRICAL CHARACTERISTICS—REF193 @ T A ≤ ?40°C ≤ +125°C

@ V S = 3.3 V , –40°C ≤ T A ≤ +125°C, unless otherwise noted. Table 10.

Parameter Mnemonic Condition Min Typ Max Unit TEMPERATURE COEFFICIENT 1 ,2

G Grade 3

TCV O /°C I OUT = 0 mA 10 ppm/°C

LINE REGULATION 4

G Grade ΔV O /ΔV IN 3.3 V ≤ V S ≤ 15 V, I OUT = 0 mA 20 ppm/V LOAD REGULATION 4 G Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 20 mA 10 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 3.8 V, I LOAD = 10 mA 0.80 V V S = 4.1 V, I LOAD = 20 mA 1.10 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF194 @ T A = 25°C

@ V S = 5.0 V , T A = 25°C, unless otherwise noted. Table 11.

Parameter Mnemonic Condition Min Typ Max Unit

INITIAL ACCURACY 1

E Grade V O I OUT = 0 mA 4.498 4.5 4.502 V

F Grade 4.495 4.505 V

G Grade 4.490 4.510 V LINE REGULATION 2 E Grade ?V O /?V IN 4.75 V ≤ V S ≤ 15 V, I OUT = 0 mA 2 4 ppm/V F and G Grades 4 8 ppm/V LOAD REGULATION 2 E Grade ?V O /?V LOAD V S = 5.8 V, 0 mA ≤ I OUT ≤ 30 mA 2 4 ppm/mA F and G Grades 4 8 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 5.00 V, I LOAD = 10 mA 0.50 V V S = 5.8 V, I LOAD = 30 mA 1.30 V LONG-TERM STABILITY 3DV O 1000 hours @ 125°C 2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz 45 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

REF19x Series

Rev. I | Page 9 of 28

ELECTRICAL CHARACTERISTICS—REF194 @ ?40°C ≤ T A ≤ +85°C

@ V S = 5.0 V , ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF194 @ ?40°C ≤ T A ≤ +125°C

@ V S = 5.0 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted.

Table 13.

Parameter Mnemonic Condition Min Typ Max Unit TEMPERATURE COEFFICIENT 1, 2 E Grade TCV O /°C I OUT = 0 mA 2 ppm/°C F Grade

5 ppm/°C G Grade 3

10 ppm/°C LINE REGULATION 4

E Grade ΔV O /ΔV IN 4.75 V ≤ V S ≤ 15 V, I OUT = 0 mA 5 ppm/V

F and

G Grades 10 ppm/V LOAD REGULATION E Grade ΔV O /ΔV LOAD V S = 5.80 V, 0 mA ≤ I OUT ≤ 20 mA 5 ppm/mA F and G Grades 10 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 5.10 V, I LOAD = 10 mA 0.60 V V S = 5.95 V, I LOAD = 20 mA

1.45 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 10 of 28

ELECTRICAL CHARACTERISTICS—REF195 @ T A = 25°C

@ V S = 5.10 V , T A = 25°C, unless otherwise noted. Table 14.

Parameter Mnemonic Condition Min Typ Max Unit

INITIAL ACCURACY 1

E Grade V O I OUT = 0 mA 4.998 5.0 5.002 V

F Grade 4.995 5.005 V

G Grade 4.990 5.010 V LINE REGULATION 2 E Grade ΔV O /ΔV IN 5.10 V ≤ V S ≤ 15 V, I OUT = 0 mA 2 4 ppm/V F and G Grades 4 8 ppm/V LOAD REGULATION 2 E Grade ΔV O /ΔV LOAD V S = 6.30 V, 0 mA ≤ I OUT ≤ 30 mA 2 4 ppm/mA F and G Grades 4 8 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 5.50 V, I LOAD = 10 mA 0.50 V V S = 6.30 V, I LOAD = 30 mA 1.30 V LONG-TERM STABILITY 3DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz 50 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

ELECTRICAL CHARACTERISTICS—REF195 @ ?40°C ≤ T A ≤ +85°C

@ V S = 5.15 V , ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 11 of 28

ELECTRICAL CHARACTERISTICS—REF195 @ ?40°C ≤ T A ≤ +125°C

@ V S = 5.20 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted. Table 16.

Parameter Mnemonic Condition Min Typ Max Unit TEMPERATURE COEFFICIENT 1, 2 E Grade TCV O /°C I OUT = 0 mA 2 ppm/°C F Grade 5 ppm/°C G Grade 3

10 ppm/°C LINE REGULATION 4

E Grade ΔV O /ΔV IN 5.20 V ≤ V S ≤ 15 V, I OUT = 0 mA 5 ppm/V

F and

G Grades

10 ppm/V LOAD REGULATION 4

E Grade ΔV O /ΔV LOAD V S = 6.45 V, 0 mA ≤ I OUT ≤ 20 mA 5 ppm/mA

F and

G Grades 10 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 5.60 V, I LOAD = 10 mA 0.60 V

V S = 6.45 V, I LOAD = 20 mA

1.45

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF196 @ T A = 25°C

@ V S = 3.5 V , T A = 25°C, unless otherwise noted. Table 17.

Parameter Mnemonic Condition Min Typ Max Unit INITIAL ACCURACY 1 G Grade V O I OUT = 0 mA

3.290 3.3 3.310 V LINE REGULATION 2

G Grade ΔV O /ΔV IN 3.50 V ≤ V S ≤ 15 V, I OUT = 0 mA 4 8 ppm/V LOAD REGULATION 2 G Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 30 mA 6 15 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 4.1 V, I LOAD = 10 mA 0.80 V V S = 4.3 V, I LOAD = 30 mA

1.00 V LONG-TERM STABILITY 3

DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz

33 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

REF19x Series

Rev. I | Page 12 of 28

ELECTRICAL CHARACTERISTICS—REF196 @ ?40°C ≤ T A ≤ +85°C

@ V S = 3.5 V , –40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF196 @ ?40°C ≤ T A ≤ +125°C

@ V S = 3.50 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted. Table 19.

Parameter Mnemonic Condition Min Typ Max Unit

TEMPERATURE COEFFICIENT 1, 2

G Grade 3TCV O /°C I OUT = 0 mA 10 ppm/°C LINE REGULATION 4 G Grade ΔV O /ΔV IN 3.50 V ≤ V S ≤ 15 V, I OUT = 0 mA 20 ppm/V LOAD REGULATION 4 G Grade ΔV O /ΔV LOAD V S = 5.0 V, 0 mA ≤ I OUT ≤ 20 mA 20 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 4.1 V, I LOAD = 10 mA 0.80 V V S = 4.4 V, I LOAD = 20 mA 1.10 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 13 of 28

ELECTRICAL CHARACTERISTICS—REF198 @ T A = 25°C

@ V S = 5.0 V , T A = 25°C, unless otherwise noted. Table 20.

Parameter Mnemonic Condition Min Typ Max Unit INITIAL ACCURACY 1 E Grade V O I OUT = 0 mA 4.094 4.096 4.098 V F Grade 4.091 4.101 V G Grade

4.086 4.106 V LINE REGULATION 2

E Grade ΔV O /ΔV IN 4.5 V ≤ V S ≤ 15 V, I OUT = 0 mA 2 4 ppm/V

F and

G Grades

4 8 ppm/V LOAD REGULATION 2

E Grade ΔV O /ΔV LOAD V S = 5.4 V, 0 mA ≤ I OUT ≤ 30 mA 2 4 ppm/mA

F and

G Grades 4 8 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 4.6 V, I LOAD = 10 mA 0.502 V V S = 5.4 V, I LOAD = 30 mA 1.30 V LONG-TERM STABILITY 3DV O 1000 hours @ 125°C 1.2 mV NOISE VOLTAGE e N 0.1 Hz to 10 Hz

40 μV p-p

1 Initial accuracy includes temperature hysteresis effect.

2 Line and load regulation specifications include the effect of self-heating. 3

Long-term stability specification is noncumulative. The drift in subsequent 1000-hour periods is significantly lower than in the first 1000-hour period.

ELECTRICAL CHARACTERISTICS—REF198 @ ?40°C ≤ T A ≤ +85°C

@ V S = 5.0 V , ?40°C ≤ T A ≤ +85°C, unless otherwise noted.

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

REF19x Series

Rev. I | Page 14 of 28

ELECTRICAL CHARACTERISTICS—REF198 @ ?40°C ≤ T A ≤ +125°C

@ V S = 5.0 V , ?40°C ≤ T A ≤ +125°C, unless otherwise noted. Table 22.

Parameter Mnemonic Condition

Min Typ Max Unit TEMPERATURE COEFFICIENT 1, 2

E Grade TCV O /°C I OUT = 0 mA 2 ppm/°C

F Grade 5 ppm/°C

G Grade 3 10 ppm/°C LINE REGULATION 4 E Grade ΔV O /ΔV IN 4.5 V ≤ V S ≤ 15 V, I OUT = 0 mA 5 ppm/V F and G Grades 10 ppm/V LOAD REGULATION 4 E Grade ΔV O /ΔV LOAD V S = 5.6 V, 0 mA ≤ I OUT ≤ 20 mA 5 ppm/mA F and G Grades 10 ppm/mA DROPOUT VOLTAGE V S ? V O V S = 4.7 V, I LOAD = 10 mA 0.60 V V S = 5.6 V, I LOAD = 20 mA

1.50 V

1 For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.

TCV O is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.

TCV O = (V MAX ? V MIN )/V O (T MAX ? T MIN ) 3

Guaranteed by characterization. 4

Line and load regulation specifications include the effect of self-heating.

WAFER TEST LIMITS

For proper operation, a 1 μF capacitor is required between the output pins and the GND pin of the REF19x. Electrical tests and wafer

probe to the limits are shown in

Table 23. 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. @ I LOAD = 0 mA, T A = 25°C, unless otherwise noted.

REF19x Series

Rev. I | Page 15 of 28

ABSOLUTE MAXIMUM RATINGS

Table 24.

Parameter 1

Rating

Supply Voltage ?0.3 V, +18 V Output to GND

?0.3 V, V S + 0.3 V Output to GND Short-Circuit Duration Indefinite Storage Temperature Range

PDIP , SOIC_N Package

?65°C to +150°C Operating Temperature Range

REF19x

?40°C to +85°C Junction Temperature Range

PDIP , SOIC_N Package

?65°C to +150°C Lead Temperature Range (Soldering 60 sec)

300°C

Absolute maximum ratings apply to both DICE and packaged parts, unless otherwise noted.

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages. Table 25. Thermal Resistance

Package Type θJA 1θJC Unit 8-Lead PDIP 103 43 °C/W 8-Lead SOIC_N

158

°C/W

θJA is specified for worst-case conditions; that is, θJA is specified for the device in socket for PDIP and is specified for the device soldered in the circuit board for the SOIC package.

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.

ESD CAUTION

REF19x Series

Rev. I | Page 16 of 28

TYPICAL PERFORMANCE CHARACTERISTICS

TEMPERATURE (°C)

100–50

–25

0255075O U T P U T V O L T A G E (V )

5.0045.0035.0015.002

5.0004.9994.9984.9974.996

3 TYPICAL PARTS 5.15V < V IN < 15V

00371-003

Figure 3. REF195 Output Voltage vs. Temperature

I LOAD (mA)

0510

2025L O A D R E G U L A T I O N (p p m /V )

3224

2016

12480

–40°C

+25°C

5.15V ≤ V S ≤ 15V

+85°C

00371-004

Figure 4. REF195 Load Regulator vs. I LOAD

V IN (V)

16468

101214L I N E R E G U L A T I O N (p p m /m A )

+85°C

+25°C

–40°C

0mA ≤ I OUT ≤ 25mA

00371-005

Figure 5. REF195 Line Regulator vs. V IN T C —V OUT (ppm/°C)

150510155P E R C E N T A G E O F P A R T S

454030352025105

150

00371-006

Figure 6. T C —V OUT Distribution

TEMPERATURE (°C)

100

–50

–25

0255075 S U P P L Y C U R R E N T (μA )

252015105

000371-007

Figure 7. Supply Current vs. Temperature

TEMPERATURE (°C)

100

–50

–25

0255075S L E E P P I N C U R R E N T (μA )

–6

–5–4

–3

–1

–2

000371-008

Figure 8. SLEEP Pin Current vs. Temperature

REF19x Series

Rev. I | Page 17 of 28

FREQUENCY (Hz)

10100

1k 10k 100k R I P P L E R E J E C T I O N (

d B )

–200–60–40–80

–120

–10000371-009

Figure 9. Ripple Rejection vs. Frequency

00371-010

V IN

Figure 10. Ripple Rejection vs. Frequency Measurement Circuit

FREQUENCY (Hz)

10M

100

10k 1k 100k 1M

Z O (?)

00371-011

Figure 11. Output Impedance vs. Frequency

OFF

00371-012

Figure 12. Load Transient Response

V IN 00371-013

Figure 13. Load Transient Response Measurement Circuit

00371-014

Figure 14. Power-On Response Time

V IN 00371-015

Figure 15. Power-On Response Time Measurement Circuit

ON V OUT

00371-016

Figure 16. SLEEP Response Time

00371-017

Figure 17. SLEEP Response Time Measurement Circuit

REF19x Series

Rev. I | Page 18 of 28

00371-018

Figure 18. Line Transient Response

REF195 DROPOUT VOLTAGE (V)

0.9

00.20.1

0.40.50.30.60.70.8L O A D C U R R E N T (m A )

302515

205

100

00371-019

Figure 19. Load Current vs. Dropout Voltage

REF19x Series

Rev. I | Page 19 of 28

APPLICATIONS

OUTPUT SHORT-CIRCUIT BEHAVIOR

The REF19x family of devices is completely protected from damage due to accidental output shorts to GND or to V +. In the event of an accidental short-circuit condition, the reference device shuts down and limits its supply current to 40 mA.

OUT

SLEEP (SHUTDOWN)

00371-020

Figure 20. Simplified Schematic

DEVICE POWER DISSIPATION CONSIDERATIONS

The REF19x family of references is capable of delivering load currents to 30 mA with an input voltage that ranges from 3.3 V to 5 V . When these devices are used in applications with large input voltages, exercise care to avoid exceeding the maximum internal power dissipation of these devices.

Exceeding the published specifications for maximum power dissipation or junction temperature can result in premature device failure. The following formula should be used to calculate a device’s maximum junction temperature or dissipation:

A J D T T P θ?=

In this equation, T J and T A are the junction and ambient

temperatures, respectively; P D is the device power dissipation; and θJA is the device package thermal resistance.

OUTPUT VOLTAGE BYPASSING

For stable operation, low dropout voltage regulators and

references generally require a bypass capacitor connected from their V OUT pins to their GND pins. Although the REF19x family of references is capable of stable operation with capacitive loads exceeding 100 μF, a 1 μF capacitor is sufficient to guarantee rated performance. The addition of a 0.1 μF ceramic capacitor in parallel with the bypass capacitor improves load current transient performance. For best line voltage transient

performance, it is recommended that the voltage inputs of these devices be bypassed with a 10 μF electrolytic capacitor in parallel with a 0.1 μF ceramic capacitor.

SLEEP MODE OPERATION

All REF19x devices include a sleep capability that is

TTL/CMOS-level compatible. Internally, a pull-up current source to V IN is connected at the SLEEP pin. This permits the SLEEP pin to be driven from an open collector/drain driver. A logic low or a 0 V condition on the SLEEP pin is required to turn off the output stage. During sleep, the output of the

references becomes a high impedance state where its potential would then be determined by external circuitry. If the sleep feature is not used, it is recommended that the SLEEP pin be connected to V IN (Pin 2).

BASIC VOLTAGE REFERENCE CONNECTIONS

The circuit in Figure 21 illustrates the basic configuration for the REF19x family of references. Note the 10 μF/0.1 μF bypass network on the input and the 1 μF/0.1 μF bypass network on the output. It is recommended that no connections be made to Pin 1, Pin 5, Pin 7, and Pin 8. If the sleep feature is not required, Pin 3 should be connected to V IN .

00371-021

Figure 21. Basic Voltage Reference Configuration

MEMBRANE SWITCH-CONTROLLED POWER SUPPLY

With output load currents in the tens of mA, the REF19x family of references can operate as a low dropout power supply in hand-held instrument applications. In the circuit shown in Figure 22, a membrane on/off switch is used to control the operation of the reference. During an initial power-on condition, the SLEEP pin is held to GND by the 10 kΩ resistor. Recall that this condition (read: three-state) disables the REF19x output. When the membrane on switch is pressed, the pin is momentarily pulled to V IN , enabling the REF19x output. At this point, current through the 10 kΩ resistor is reduced, and the internal current source connected to the SLEEP pin takes

control. Pin 3 assumes and remains at the same potential as V IN . When the membrane off switch is pressed, the SLEEP pin is momentarily connected to GND, which once again disables the REF19x output.

REF19x Series

Rev. I | Page 20 of 28

00371-022

Figure 22. Membrane Switch-Controlled Power Supply

CURRENT-BOOSTED REFERENCES WITH CURRENT LIMITING

While the 30 mA rated output current of the REF19x series is higher than is typical of other reference ICs, it can be boosted to higher levels, if desired, with the addition of a simple external PNP transistor, as shown in Figure 23. Full-time current limiting is used to protect the pass transistor against shorts.

+V = 6V V 00371-023

Figure 23. Boosted 3.3 V Referenced with Current Limiting

In this circuit, the power supply current of reference U1 flowing through R1 to R2 develops a base drive for Q1, whose collector provides the bulk of the output current. With a typical gain of 100 in Q1 for 100 mA to 200 mA loads, U1 is never required to furnish more than a few mA, so this factor minimizes tempera-ture-related drift. Short-circuit protection is provided by Q2, which clamps the drive to Q1 at about 300 mA of load current, with values as shown in Figure 23. With this separation of control and power functions, dc stability is optimum, allowing most advantageous use of premium grade REF19x devices for U1. Of course, load management should still be exercised. A short, heavy, low dc resistance (DCR) conductor should be used from U1 to U6 to the V OUT Sense Point S, where the collector of Q1 connects to the load, Point F.

Because of the current limiting configuration, the dropout voltage circuit is raised about 1.1 V over that of the REF19x devices, due to the V BE of Q1 and the drop across Current Sense Resistor R4. However, overall dropout is typically still low

enough to allow operation of a 5 V to 3.3 V regulator/reference using the REF196 for U1 as noted, with a V S as low as 4.5 V and a load current of 150 mA.

The requirement for a heat sink on Q1 depends on the maximum input voltage and short-circuit current. With V S = 5 V and a 300 mA current limit, the worst-case dissipation of Q1 is 1.5 W , less than the TO-220 package 2 W limit. However, if smaller TO-39 or TO-5 packaged devices, such as the 2N4033, are used, the current limit should be reduced to keep maximum dissipation below the package rating. This is accomplished by simply raising R4.

A tantalum output capacitor is used at C1 for its low equivalent series resistance (ESR), and the higher value is required for stability. Capacitor C2 provides input bypassing and can be an ordinary electrolytic.

Shutdown control of the booster stage is an option, and when used, some cautions are needed. Due to the additional active devices in the V S line to U1, a direct drive to Pin 3 does not

work as with an unbuffered REF19x device. To enable shutdown control, the connection from U1 to U2 is broken at the X, and Diode D1 then allows a CMOS control source, V C , to drive U1 to U3 for on/off operation. Startup from shutdown is not as clean under heavy load as it is in basic REF19x series, and can require several milliseconds under load. Nevertheless, it is still effective and can fully control 150 mA loads. When shutdown control is used, heavy capacitive loads should be minimized.

NEGATIVE PRECISION REFERENCE WITHOUT PRECISION RESISTORS

In many current-output CMOS DAC applications where the output signal voltage must be the same polarity as the reference voltage, it is often necessary to reconfigure a current-switching DAC into a voltage-switching DAC using a 1.25 V reference, an op amp, and a pair of resistors. Using a current-switching DAC directly requires an additional operational amplifier at the output to reinvert the signal. A negative voltage reference is then desirable, because an additional operational amplifier is not required for either reinversion (current-switching mode) or amplification (voltage-switching mode) of the DAC output voltage. In general, any positive voltage reference can be

converted into a negative voltage reference using an operational amplifier and a pair of matched resistors in an inverting configuration. The disadvantage to this approach is that the largest single source of error in the circuit is the relative matching of the resistors used.

The circuit illustrated in Figure 24 avoids the need for tightly matched resistors by using an active integrator circuit. In this circuit, the output of the voltage reference provides the input drive for the integrator. To maintain circuit equilibrium, the integrator adjusts its output to establish the proper relationship between the reference’s V OUT and GND. Thus, any desired negative output voltage can be selected by substituting for the appropriate reference IC. The sleep feature is maintained in the circuit with the simple addition of a PNP transistor and a 10 kΩ resistor.