Precision Micropower,

Low Dropout Voltage References

Data Sheet REF19x Series
FEATURES TEST PINS
Temperature coefficient: 5 ppm/°C maximum Test Pin 1 and Test Pin 5 are reserved for in-package Zener zap.
High output current: 30 mA To achieve the highest level of accuracy at the output, the Zener
Low supply current: 45 μA maximum zapping technique is used to trim the output voltage. Because
Initial accuracy: ±2 mV maximum 1 each unit may require a different amount of adjustment, the
Sleep mode: 15 μA maximum resistance value at the test pins varies widely from pin to pin
Low dropout voltage and from part to part. The user should leave Pin 1 and Pin 5
Load regulation: 4 ppm/mA unconnected.
Line regulation: 4 ppm/V
TP 1 8 NC
Short-circuit protection REF19x
VS 2 SERIES 7 NC
SLEEP 3 TOP VIEW 6 OUTPUT

GND 4 (Not to Scale) 5 TP

APPLICATIONS
Portable instruments NOTES
ADCs and DACs 1. NC = NO CONNECT.

00371-001
2. TP PINS ARE FACTORY TEST
Smart sensors POINTS, NO USER CONNECTION.
Solar powered applications Figure 1. 8-Lead SOIC_N and TSSOP Pin Configuration
Loop-current-powered instruments (S Suffix and RU Suffix)

TP 1 8 NC
REF19x
VS 2 NC
GENERAL DESCRIPTION SERIES
7

SLEEP 3 6 OUTPUT
TOP VIEW
The REF19x series precision band gap voltage references use a GND 4 (Not to Scale) 5 TP
patented temperature drift curvature correction circuit and
laser trimming of highly stable, thin-film resistors to achieve a NOTES
1. NC = NO CONNECT.

00371-002
very low temperature coefficient and high initial accuracy. 2. TP PINS ARE FACTORY TEST
POINTS, NO USER CONNECTION.
The REF19x series is made up of micropower, low dropout Figure 2. 8-Lead PDIP Pin Configuration
voltage (LDV) devices, providing stable output voltage from (P Suffix)
supplies as low as 100 mV above the output voltage and
Table 1. Nominal Output Voltage
consuming less than 45 μA of supply current. In sleep mode,
Part Number Nominal Output Voltage (V)
which is enabled by applying a low TTL or CMOS level to the
SLEEP pin, the output is turned off and supply current is REF191 2.048
REF192 2.50
further reduced to less than 15 μA.
REF193 3.00
The REF19x series references are specified over the extended REF194 4.50
industrial temperature range (−40°C to +85°C) with typical REF195 5.00
performance specifications over −40°C to +125°C for REF196 3.30
applications, such as automotive. REF198 4.096
All electrical grades are available in an 8-lead SOIC package; the
PDIP and TSSOP packages are available only in the lowest
electrical grade.
1
Initial accuracy does not include shift due to solder heat effect (see the
Applications Information section).

Rev. L
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
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Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 ©1996–2011 Analog Devices, Inc. All rights reserved.
REF19x Series Data Sheet

TABLE OF CONTENTS
Features .............................................................................................. 1 Electrical Characteristics—REF196 @ −40°C ≤ TA ≤ +125°C
Applications....................................................................................... 1 ....................................................................................................... 13

General Description ......................................................................... 1 Electrical Characteristics—REF198 @ TA = 25°C.................. 14

Test Pins ............................................................................................. 1 Electrical Characteristics—REF198 @ −40°C ≤ TA ≤ +85°C

....................................................................................................... 14
Revision History ............................................................................... 3
Electrical Characteristics—REF198 @ −40°C ≤ TA ≤ 125°C15
Specifications..................................................................................... 4
Absolute Maximum Ratings ......................................................... 16
Electrical Characteristics—REF191 @ TA = 25°C .................... 4
Thermal Resistance .................................................................... 16
Electrical Characteristics—REF191 @ −40°C ≤ +85°C........... 5
ESD Caution................................................................................ 16
Electrical Characteristics—REF191 @
−40°C ≤ TA ≤ +125°C................................................................... 6 Typical Performance Characteristics ........................................... 17

Electrical Characteristics—REF192 @ TA = 25°C .................... 6 Applications Information .............................................................. 20

Electrical Characteristics—REF192 @ −40°C ≤ TA ≤ +85°C Output Short-Circuit Behavior ................................................ 20

......................................................................................................... 7 Device Power Dissipation Considerations.............................. 20
Electrical Characteristics—REF192 @ −40°C ≤ TA ≤ +125°C Output Voltage Bypassing ......................................................... 20
......................................................................................................... 7 Sleep Mode Operation............................................................... 20
Electrical Characteristics—REF193 @ TA = 25°C .................... 8 Basic Voltage Reference Connections ..................................... 20
Electrical Characteristics—REF193 @ −40°C ≤ TA ≤ +85°C Membrane Switch-Controlled Power Supply............................. 20
......................................................................................................... 8
Solder Hear Effect ...................................................................... 21
Electrical Characteristics—REF193 @ TA ≤ −40°C ≤ +125°C
......................................................................................................... 9 Current-Boosted References with Current Limiting............. 21

Electrical Characteristics—REF194 @ TA = 25°C .................... 9 Negative Precision Reference Without Precision Resistors.. 22

Electrical Characteristics—REF194 @ −40°C ≤ TA ≤ +85°C Stacking Reference ICs for Arbitrary Outputs ....................... 22
....................................................................................................... 10 Precision Current Source .......................................................... 23
Electrical Characteristics—REF194 @ −40°C ≤ TA ≤ +125°C Switched Output 5 V/3.3 V Reference..................................... 23
....................................................................................................... 10 Kelvin Connections.................................................................... 24
Electrical Characteristics—REF195 @ TA = 25°C .................. 11 Fail-Safe 5 V Reference.............................................................. 24
Electrical Characteristics—REF195 @ −40°C ≤ TA ≤ +85°C Low Power, Strain Gage Circuit ............................................... 25
....................................................................................................... 11
Outline Dimensions ....................................................................... 26
Electrical Characteristics—REF195 @ −40°C ≤ TA ≤ +125°C
....................................................................................................... 12 Ordering Guide .......................................................................... 27

Electrical Characteristics—REF196 @ TA = 25°C .................. 12

Electrical Characteristics—REF196 @ −40°C ≤ TA ≤ +85°C
....................................................................................................... 13

Rev. L | Page 2 of 28
Data Sheet REF19x Series
REVISION HISTORY
9/11—Rev. K to Rev. L Changes to Precision Current Source Section ............................ 22
Change to Condition Column for Dropout Voltage Parameter, Changes to Figure 28 ...................................................................... 23
Table 2 ................................................................................................. 4 Changes to Figure 30 ...................................................................... 24
Change to Condition Column for Dropout Voltage Parameter, Changes to Low Power, Strain Gage Circuit Section.................. 25
Table 3 ................................................................................................. 5 Changes to Ordering Guide ........................................................... 27
Change to Operating Temperature Range, Table 23...................16 9/06—Rev. H to Rev. I
7/10—Rev. J to Rev. K Updated Format ................................................................. Universal
Add Note 1, Features Section........................................................... 1 Changes to Table 25 ........................................................................ 16
Changes to Note 1, Table 2 ............................................................... 4 Changes to Figure 6 ........................................................................ 16
Changes to Note 1, Table 5 ............................................................... 6 Changes to Figure 10, Figure 12, Figure 14, and Figure 26 ....... 17
Changes to Note 1, Table 8 ............................................................... 8 Changes to Figure 18 ...................................................................... 18
Changes to Note 1, Table 11 ............................................................. 9 Changes to Figure 20 ...................................................................... 19
Changes to Note 1, Table 14 ...........................................................11 Changes to Figure 23 ...................................................................... 20
Changes to Note 1, Table 17 ...........................................................12 Changes to Figure 25 ...................................................................... 21
Changes to Note 1, Table 20 ...........................................................14 Updated Outline Dimensions........................................................ 25
Moved Figure 22 ..............................................................................20 Changes to Ordering Guide ........................................................... 26
Added Figure 23, Solder Heat Effect Section, and Figure 24; 6/05—Rev. G to Rev. H
Renumbered Sequentially ..............................................................21 Updated Format ................................................................. Universal
Moved Negative Precision Reference Without Precision Changes to Caption in Figure 7..................................................... 16
Resistors Section ..............................................................................22 Updated Outline Dimensions........................................................ 25
Moved Precision Current Source Section ....................................23 Changes to Ordering Guide ........................................................... 26
Moved Kelvin Connections Section .............................................24
7/04—Rev. F to Rev. G
Moved Figure 32 ..............................................................................25
Changes to Ordering Guide ............................................................. 4
Updated Outline Dimensions ........................................................26
Changes to Ordering Guide ...........................................................27 3/04—Rev. E to Rev. F
Updated Absolute Maximum Rating.............................................. 4
3/08—Rev. I to Rev. J
Changes to Ordering Guide ........................................................... 14
Changes to General Description ..................................................... 1
Updated Outline Dimensions........................................................ 24
Changes to Specifications Section................................................... 4
Deleted Wafer Test Limits Section ................................................14 1/03—Rev. D to Rev. E
Changes to Table 23, Thermal Resistance Section, and Changes to Figure 3 and Figure 4 ................................................. 15
Table 24 .............................................................................................16 Changes to Output Short Circuit Behavior ................................. 17
Changes to Figure 6.........................................................................17 Changes to Figure 20 ...................................................................... 17
Changes to Device Power Dissipation Changes to Figure 26 ...................................................................... 19
Considerations Section ...................................................................20 Updated Outline Dimensions........................................................ 23
Changes to Current-Boosted References with Current 1/96—Revision 0: Initial Version
Limiting Section ..............................................................................21

Rev. L | Page 3 of 28
REF19x Series Data Sheet

SPECIFICATIONS
ELECTRICAL CHARACTERISTICS—REF191 @ TA = 25°C
@ VS = 3.3 V, TA = 25°C, unless otherwise noted.

Table 2.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
E Grade IOUT = 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 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 2 4 ppm/V
F and G Grades 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 30 mA 4 10 ppm/mA
F and G Grades 6 15 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.0 V, ILOAD = 2 mA 0.95 V
VS = 3.3 V, ILOAD = 10 mA 1.25 V
VS = 3.6 V, ILOAD = 30 mA 1.55 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 20 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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.

Rev. L | Page 4 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF191 @ −40°C ≤ +85°C
@ VS = 3.3 V, −40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 3.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 5 ppm/°C
F Grade 5 10 ppm/°C
G Grade 3 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 10 ppm/V
F and G Grades 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 25 mA 5 15 ppm/mA
F and G Grades 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.0 V, ILOAD = 2 mA 0.95 V
VS = 3.3 V, ILOAD = 10 mA 1.25 V
VS = 3.6 V, ILOAD = 25 mA 1.55 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 5 of 28
REF19x Series Data Sheet
ELECTRICAL CHARACTERISTICS—REF191 @ −40°C ≤ TA ≤ +125°C
@ VS = 3.3 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 4.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 ppm/°C
F Grade 5 ppm/°C
G Grade 3 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 10 ppm/V
F and G Grades 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 20 mA 10 ppm/mA
F and G Grades 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.3 V, ILOAD = 10 mA 1.25 V
VS = 3.6 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF192 @ TA = 25°C

@ VS = 3.3 V, TA = 25°C, unless otherwise noted.

Table 5.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
E Grade IOUT = 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 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 2 4 ppm/V
F and G Grades 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 30 mA 4 10 ppm/mA
F and G Grades 6 15 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.5 V, ILOAD = 10 mA 1.00 V
VS = 3.9 V, ILOAD = 30 mA 1.40 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 25 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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.

Rev. L | Page 6 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF192 @ −40°C ≤ TA ≤ +85°C
@ VS = 3.3 V, −40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 6.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 5 ppm/°C
F Grade 5 10 ppm/°C
G Grade 3 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 10 ppm/V
F and G Grades 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 25 mA 5 15 ppm/mA
F and G Grades 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.5 V, ILOAD = 10 mA 1.00 V
VS = 4.0 V, ILOAD = 25 mA 1.50 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF192 @ −40°C ≤ TA ≤ +125°C

@ VS = 3.3 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 7.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 ppm/°C
F Grade 5 ppm/°C
G Grade 3 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 3.0 V ≤ VS ≤ 15 V, IOUT = 0 mA 10 ppm/V
F and G Grades 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 20 mA 10 ppm/mA
F and G Grades 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.5 V, ILOAD = 10 mA 1.00 V
VS = 4.0 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 7 of 28
REF19x Series Data Sheet
ELECTRICAL CHARACTERISTICS—REF193 @ TA = 25°C
@ VS = 3.3 V, TA = 25°C, unless otherwise noted.

Table 8.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
G Grade IOUT = 0 mA 2.990 3.0 3.010 V
LINE REGULATION 2 ΔVO/ΔVIN
G Grade 3.3 V, ≤ VS ≤ 15 V, IOUT = 0 mA 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 30 mA 6 15 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.8 V, ILOAD = 10 mA 0.80 V
VS = 4.0 V, ILOAD = 30 mA 1.00 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 30 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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—REF193 @ −40°C ≤ TA ≤ +85°C

@ VS = 3.3 V, TA = −40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 9.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
G Grade 3 IOUT = 0 mA 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
G Grade 3.3 V ≤ VS ≤ 15 V, IOUT = 0 mA 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 25 mA 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.8 V, ILOAD = 10 mA 0.80 V
VS = 4.1 V, ILOAD = 30 mA 1.10 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 8 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF193 @ TA ≤ −40°C ≤ +125°C
@ VS = 3.3 V, –40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 10.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
G Grade 3 IOUT = 0 mA 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
G Grade 3.3 V ≤ VS ≤ 15 V, IOUT = 0 mA 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 20 mA 10 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 3.8 V, ILOAD = 10 mA 0.80 V
VS = 4.1 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF194 @ TA = 25°C

@ VS = 5.0 V, TA = 25°C, unless otherwise noted.

Table 11.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
E Grade IOUT = 0 mA 4.498 4.5 4.502 V
G Grade 4.490 4.510 V
LINE REGULATION 2 ∆VO/∆VIN
E Grade 4.75 V ≤ VS ≤ 15 V, IOUT = 0 mA 2 4 ppm/V
G Grade 4 8 ppm/V
LOAD REGULATION2 ∆VO/∆VLOAD
E Grade VS = 5.8 V, 0 mA ≤ IOUT ≤ 30 mA 2 4 ppm/mA
G Grade 4 8 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 5.00 V, ILOAD = 10 mA 0.50 V
VS = 5.8 V, ILOAD = 30 mA 1.30 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 45 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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.

Rev. L | Page 9 of 28
REF19x Series Data Sheet
ELECTRICAL CHARACTERISTICS—REF194 @ −40°C ≤ TA ≤ +85°C
@ VS = 5.0 V, TA = −40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 12.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 5 ppm/°C
G Grade 3 10 25 ppm/°C
LINE REGULATION 4 ∆VO/∆VIN
E Grade 4.75 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 10 ppm/V
G Grade 10 20 ppm/V
LOAD REGULATION4 ∆VO/∆VLOAD
E Grade VS = 5.80 V, 0 mA ≤ IOUT ≤ 25 mA 5 15 ppm/mA
G Grade 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 5.00 V, ILOAD = 10 mA 0.5 V
VS = 5.80 V, ILOAD = 25 mA 1.30 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF194 @ −40°C ≤ TA ≤ +125°C

@ VS = 5.0 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 13.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 ppm/°C
G Grade 3 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 4.75 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 ppm/V
G Grade 10 ppm/V
LOAD REGULATION ΔVO/ΔVLOAD
E Grade VS = 5.80 V, 0 mA ≤ IOUT ≤ 20 mA 5 ppm/mA
Grade 10 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 5.10 V, ILOAD = 10 mA 0.60 V
VS = 5.95 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 10 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF195 @ TA = 25°C
@ VS = 5.10 V, TA = 25°C, unless otherwise noted.
Table 14.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
E Grade IOUT = 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 ΔVO/ΔVIN
E Grade 5.10 V ≤ VS ≤ 15 V, IOUT = 0 mA 2 4 ppm/V
F and G Grades 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
E Grade VS = 6.30 V, 0 mA ≤ IOUT ≤ 30 mA 2 4 ppm/mA
F and G Grades 4 8 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 5.50 V, ILOAD = 10 mA 0.50 V
VS = 6.30 V, ILOAD = 30 mA 1.30 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 50 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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—REF195 @ −40°C ≤ TA ≤ +85°C

@ VS = 5.15 V, TA = −40°C ≤ TA ≤ +85°C, unless otherwise noted.
Table 15.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 5 ppm/°C
F Grade 5 10 ppm/°C
G Grade 3 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 5.15 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 10 ppm/V
F and G Grades 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 6.30 V, 0 mA ≤ IOUT ≤ 25 mA 5 10 ppm/mA
F and G Grades 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 5.50 V, ILOAD = 10 mA 0.50 V
VS = 6.30 V, ILOAD = 25 mA 1.30 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 11 of 28
REF19x Series Data Sheet
ELECTRICAL CHARACTERISTICS—REF195 @ −40°C ≤ TA ≤ +125°C
@ VS = 5.20 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 16.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 ppm/°C
F Grade 5 ppm/°C
G Grade 3 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 5.20 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 ppm/V
F and G Grades 10 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 6.45 V, 0 mA ≤ IOUT ≤ 20 mA 5 ppm/mA
F and G Grades 10 ppm/mA
DROPOUT VOLTAGE VS − V O VS = 5.60 V, ILOAD = 10 mA 0.60 V
VS = 6.45 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF196 @ TA = 25°C

@ VS = 3.5 V, TA = 25°C, unless otherwise noted.

Table 17.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
G Grade IOUT = 0 mA 3.290 3.3 3.310 V
LINE REGULATION 2 ΔVO/ΔVIN
G Grade 3.50 V ≤ VS ≤ 15 V, IOUT = 0 mA 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 30 mA 6 15 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.1 V, ILOAD = 10 mA 0.80 V
VS = 4.3 V, ILOAD = 30 mA 1.00 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 33 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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.

Rev. L | Page 12 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF196 @ −40°C ≤ TA ≤ +85°C
@ VS = 3.5 V, TA = –40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 18.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
G Grade 3 IOUT = 0 mA 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
G Grade 3.5 V ≤ VS ≤ 15 V, IOUT = 0 mA 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 25 mA 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.1 V, ILOAD = 10 mA 0.80 V
VS = 4.3 V, ILOAD = 25 mA 1.00 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/V0(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

ELECTRICAL CHARACTERISTICS—REF196 @ −40°C ≤ TA ≤ +125°C

@ VS = 3.50 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 19.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
G Grade 3 IOUT = 0 mA 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
G Grade 3.50 V ≤ VS ≤ 15 V, IOUT = 0 mA 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
G Grade VS = 5.0 V, 0 mA ≤ IOUT ≤ 20 mA 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.1 V, ILOAD = 10 mA 0.80 V
VS = 4.4 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 13 of 28
REF19x Series Data Sheet
ELECTRICAL CHARACTERISTICS—REF198 @ TA = 25°C
@ VS = 5.0 V, TA = 25°C, unless otherwise noted.

Table 20.
Parameter Symbol Condition Min Typ Max Unit
INITIAL ACCURACY 1 VO
E Grade IOUT = 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 ΔVO/ΔVIN
E Grade 4.5 V ≤ VS ≤ 15 V, IOUT = 0 mA 2 4 ppm/V
F and G Grades 4 8 ppm/V
LOAD REGULATION2 ΔVO/ΔVLOAD
E Grade VS = 5.4 V, 0 mA ≤ IOUT ≤ 30 mA 2 4 ppm/mA
F and G Grades 4 8 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.6 V, ILOAD = 10 mA 0.502 V
VS = 5.4 V, ILOAD = 30 mA 1.30 V
LONG-TERM STABILITY 3 DVO 1000 hours @ 125°C 1.2 mV
NOISE VOLTAGE eN 0.1 Hz to 10 Hz 40 μV p-p
1
Initial accuracy does not include shift due to solder heat effect (see the Applications Information section).
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 ≤ TA ≤ +85°C

@ VS = 5.0 V, −40°C ≤ TA ≤ +85°C, unless otherwise noted.

Table 21.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 5 ppm/°C
F Grade 5 10 ppm/°C
G Grade 3 10 25 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 4.5 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 10 ppm/V
F and G Grades 10 20 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.4 V, 0 mA ≤ IOUT ≤ 25 mA 5 10 ppm/mA
F and G Grades 10 20 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.6 V, ILOAD = 10 mA 0.502 V
VS = 5.4 V, ILOAD = 25 mA 1.30 V
SLEEP PIN
Logic High Input Voltage VH 2.4 V
Logic High Input Current IH −8 μA
Logic Low Input Voltage VL 0.8 V
Logic Low Input Current IL −8 μA
SUPPLY CURRENT No load 45 μA
Sleep Mode No load 15 μA
1
For proper operation, a 1 μF capacitor is required between the output pin and the GND pin of the device.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 14 of 28
Data Sheet REF19x Series
ELECTRICAL CHARACTERISTICS—REF198 @ −40°C ≤ TA ≤ +125°C
@ VS = 5.0 V, −40°C ≤ TA ≤ +125°C, unless otherwise noted.

Table 22.
Parameter Symbol Condition Min Typ Max Unit
TEMPERATURE COEFFICIENT 1, 2 TCVO/°C
E Grade IOUT = 0 mA 2 ppm/°C
F Grade 5 ppm/°C
G Grade 3 10 ppm/°C
LINE REGULATION 4 ΔVO/ΔVIN
E Grade 4.5 V ≤ VS ≤ 15 V, IOUT = 0 mA 5 ppm/V
F and G Grades 10 ppm/V
LOAD REGULATION4 ΔVO/ΔVLOAD
E Grade VS = 5.6 V, 0 mA ≤ IOUT ≤ 20 mA 5 ppm/mA
F and G Grades 10 ppm/mA
DROPOUT VOLTAGE V S − VO VS = 4.7 V, ILOAD = 10 mA 0.60 V
VS = 5.6 V, ILOAD = 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.
2
TCVO is defined as the ratio of output change with temperature variation to the specified temperature range expressed in ppm/°C.
TCVO = (VMAX − VMIN)/VO(TMAX − TMIN)
3
Guaranteed by characterization.
4
Line and load regulation specifications include the effect of self-heating.

Rev. L | Page 15 of 28
REF19x Series Data Sheet

ABSOLUTE MAXIMUM RATINGS

Table 23. THERMAL RESISTANCE
Parameter Rating θJA is specified for worst-case conditions; that is, θJA is specified
Supply Voltage −0.3 V to +18 V for the device in socket for PDIP and is specified for the device
Output to GND −0.3 V to VS + 0.3 V soldered in the circuit board for the SOIC and TSSOP packages.
Output to GND Short-Circuit Duration Indefinite
Table 24.
Storage Temperature Range
PDIP, SOIC Package −65°C to +150°C Package Type θJA θJC Unit
Operating Temperature Range 8-Lead PDIP (N) 103 43 °C/W
REF19x −40°C to +125°C 8-Lead SOIC (R) 158 43 °C/W
Junction Temperature Range 8-Lead TSSOP (RU) 240 43 °C/W
PDIP, SOIC Package −65°C to +150°C
Lead Temperature (Soldering 60 sec) 300°C ESD CAUTION
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.

Rev. L | Page 16 of 28
Data Sheet REF19x Series

TYPICAL PERFORMANCE CHARACTERISTICS

5.004 50
3 TYPICAL PARTS BASED ON 600
5.15V < VIN < 15V 45 UNITS, 4 RUNS
5.003
–40°C ≤ TA ≤ +85°C
40
5.002

PERCENTAGE OF PARTS
35
OUTPUT VOLTAGE (V)

5.001 30

5.000 25

20
4.999
15
4.998
10
4.997 5

4.996 0

00371-003

00371-006
–50 –25 0 25 50 75 100 –20 –15 –10 –5 0 5 10 15 20
TEMPERATURE (°C) TCVOUT (ppm/°C)

Figure 3. REF195 Output Voltage vs. Temperature Figure 6. TCVOUT Distribution

32 40
5.15V ≤ VS ≤ 15V

28 35
NORMAL MODE
24 30
LOAD REGULATION (ppm/V)

SUPPLY CURRENT (μA)

–40°C
20 25

16 20
+25°C
12 15
+85°C

8 10

4 5
SLEEP MODE
0 0

00371-007
00371-004

0 5 10 15 20 25 30 –50 –25 0 25 50 75 100

ILOAD (mA) TEMPERATURE (°C)

Figure 4. REF195 Load Regulator vs. ILOAD Figure 7. Supply Current vs. Temperature

20 –6
0mA ≤ IOUT ≤ 25mA

+85°C –5
16
LINE REGULATION (ppm/mA)

SLEEP PIN CURRENT (µA)

+25°C –4
12
–40°C
–3

8
–2
VL
4
–1 VH

0 0
00371-008
00371-005

4 6 8 10 12 14 16 –50 –25 0 25 50 75 100

VIN (V) TEMPERATURE (°C)

Figure 5. REF195 Line Regulator vs. VIN Figure 8. SLEEP Pin Current vs. Temperature

Rev. L | Page 17 of 28
REF19x Series Data Sheet

0 5V
OFF 100%

–20 90%
ON
RIPPLE REJECTION (dB)

–40

–60

–80

–100
10%
–120
0%

00371-012
20mV 100µs

00371-009
10 100 1k 10k 100k 1M
FREQUENCY (Hz)

Figure 9. Ripple Rejection vs. Frequency Figure 12. Load Transient Response

10μF
REF19x
VIN = 15V 2
6
1kΩ
REF19x 10μF
4 10mA

00371-013
VIN = 15V 2 6 OUTPUT 1μF
0
10μF 4 1μF 1kΩ
00371-010

REF

Figure 10. Ripple Rejection vs. Frequency Measurement Circuit Figure 13. Load Transient Response Measurement Circuit

VIN = 7V REF19x 200V 2V

2 6
100%
4 VG = 2V p-p
90%
1μF 1μF VS = 4V
Z
ZO (Ω)

4
1mA
3 LOAD
30mA
2 LOAD
10%

1 0%

00371-014
2V 100µs
0
00371-011

10 100 1k 10k 100k 1M 10M

FREQUENCY (Hz)

Figure 11. Output Impedance vs. Frequency Figure 14. Power-On Response Time

REF19x
2
6
VIN = 7V 4
00371-015

1μF

Figure 15. Power-On Response Time Measurement Circuit

Rev. L | Page 18 of 28
Data Sheet REF19x Series

5V 5V
ON 100% 100%

90%
90%
OFF

IL = 1mA
VOUT
IL = 10mA

10% 10%

0% 0%
2ms

00371-018
1V 200mV 200µs

00371-016
Figure 16. SLEEP Response Time Figure 18. Line Transient Response

35
VIN = 15V REF19x
2 VOUT
6 30
3
1μF
00371-017

4
25

LOAD CURRENT (mA)

20
Figure 17. SLEEP Response Time Measurement Circuit

15

10

00371-019
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
REF195 DROPOUT VOLTAGE (V)

Figure 19. Load Current vs. REF195 Dropout Voltage

Rev. L | Page 19 of 28
REF19x Series Data Sheet

APPLICATIONS INFORMATION
OUTPUT SHORT-CIRCUIT BEHAVIOR SLEEP MODE OPERATION
The REF19x family of devices is totally protected from damage All REF19x devices include a sleep capability that is TTL/CMOS-
due to accidental output shorts to GND or to VS. In the event of level compatible. Internally, a pull-up current source to VS is
an accidental short-circuit condition, the reference device shuts connected at the SLEEP pin. This permits the SLEEP pin to be
down and limits its supply current to 40 mA. driven from an open collector/drain driver. A logic low or a 0 V
VS 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
OUTPUT by external circuitry. If the sleep feature is not used, it is
recommended that the SLEEP pin be connected to VS (Pin 2).

SLEEP (SHUTDOWN) 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
00371-020

GND
Pin 1, Pin 5, Pin 7, and Pin 8. If the sleep feature is not required,
Figure 20. Simplified Schematic Pin 3 should be connected to VS.
REF19x
DEVICE POWER DISSIPATION CONSIDERATIONS NC 1 8 NC
VS
The REF19x family of references is capable of delivering load 2 7 NC
currents to 30 mA with an input voltage that ranges from 3.3 V 10µF 0.1µF OUTPUT
SLEEP 3 6
+
to 15 V. When these devices are used in applications with large 4 5 NC
1µF 0.1µF

00371-021
TANT
input voltages, exercise care to avoid exceeding the maximum
NC = NO CONNECT
internal power dissipation of these devices. Exceeding the
Figure 21. Basic Voltage Reference Connections
published specifications for maximum power dissipation or
junction temperature can result in premature device failure. MEMBRANE SWITCH-CONTROLLED POWER SUPPLY
The following formula should be used to calculate the maximum With output load currents in the tens of mA, the REF19x family of
junction temperature or dissipation of the device: references can operate as a low dropout power supply in hand-held
TJ − TA instrument applications. In the circuit shown in Figure 22, a
PD = membrane on/off switch is used to control the operation of the
θJA
reference. During an initial power-on condition, the SLEEP pin is
where TJ and TA are the junction and ambient temperatures, held to GND by the 10 kΩ resistor. Recall that this condition (read:
respectively; PD is the device power dissipation; and θJA is the three-state) disables the REF19x output. When the membrane on
device package thermal resistance. switch is pressed, the SLEEP pin is momentarily pulled to VS,
OUTPUT VOLTAGE BYPASSING enabling the REF19x output. At this point, current through the 10 kΩ
resistor is reduced and the internal current source connected to the
For stable operation, low dropout voltage regulators and references
SLEEP pin takes control. Pin 3 assumes and remains at the same
generally require a bypass capacitor connected from their VOUT
potential as VS. When the membrane off switch is pressed, the
pins to their GND pins. Although the REF19x family of references is
SLEEP pin is momentarily connected to GND, which once
capable of stable operation with capacitive loads exceeding 100 μF,
again disables the REF19x output.
a 1 μF capacitor is sufficient to guarantee rated performance.
The addition of a 0.1 μF ceramic capacitor in parallel with the REF19x
NC 1 8 NC
bypass capacitor improves load current transient performance. VS
For best line voltage transient performance, it is recommended 2 7 NC
1kΩ OUTPUT
3 6
that the voltage inputs of these devices be bypassed with a 10 μF 5% +1µF
electrolytic capacitor in parallel with a 0.1 μF ceramic capacitor. 4 5 NC TANT
ON

10kΩ
00371-022

OFF NC = NO CONNECT

Figure 22. Membrane Switch Controlled Power Supply

Rev. L | Page 20 of 28
Data Sheet REF19x Series
SUPPLIER USER
TP ≥ TC TP ≤ TC
TC

TC = –5°C
SUPPLIER tP USER tP

TP
TC = –5°C
MAXIMUM RAMP UP RATE = 3°C/s tP
MAXIMUM RAMP DOWN RATE = 6°C/s
TEMPERATURE

TL
tL
TSMAX PREHEAT AREA

TSMIN

tS

25

00371-123
TIME 25°C TO PEAK
TIME
Figure 23. Classification Profile (Not to Scale)

SOLDER HEAT EFFECT CURRENT-BOOSTED REFERENCES WITH CURRENT

The mechanical stress and heat effect of soldering a part to a LIMITING
PCB can cause output voltage of a reference to shift in value. Whereas the 30 mA rated output current of the REF19x series is
The output voltage of REF195 shifts after the part undergoes the higher than is typical of other reference ICs, it can be boosted to
extreme heat of a lead-free soldering profile, like the one shown higher levels, if desired, with the addition of a simple external
in Figure 23. The materials that make up a semiconductor device PNP transistor, as shown in Figure 25. Full-time current limiting is
and its package have different rates of expansion and contraction. used to protect the pass transistor against shorts.
The stress on the dice has changed position, causing shift on the +VS = 6V Q1 OUTPUT TABLE
TO 9V R4 TIP32A
output voltage, after exposed to extreme soldering temperatures. (SEE TEXT) 2Ω (SEE TEXT)
U1 VOUT (V)
This shift is similar but more severe than thermal hysteresis. R1
REF192 2.5
REF193 3.0
Q2 1kΩ
Typical result of soldering temperature effect on REF19x output REF196 3.3
2N3906 REF194 4.5
C2 + R2
value shift is shown in Figure 24. It shows the output shift due 100µF 1.5kΩ REF195 5.0
to soldering and does not include mechanical stress. 25V
2 C3 F
6 D1 U1 0.1µF +VOUT
S
VC 3 REF196 6 3.3V
1N4148 (SEE TABLE) @ 150mA
5 C1
(SEE TEXT 4
10µF/25V
ON SLEEP) R3 +
1.82kΩ (TANTALUM) R1
S
NUMBER OF UNITS

4
VOUT 00371-023
VS F COMMON
3 COMMON
Figure 25. Boosted 3.3 V Referenced with Current Limiting
2 In this circuit, the power supply current of reference U1 flowing
through R1 to R2 develops a base drive for Q1, whose collector
1 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
0 more than a few mA, so this factor minimizes temperature-related
0
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
–0.16
–0.14
–0.12
–0.10
–0.08
–0.06
–0.04
–0.02

00371-124

drift. Short-circuit protection is provided by Q2, which clamps

SHIFT DUE TO SOLDER HEAT EFFECT (%)
the drive to Q1 at about 300 mA of load current, with values as
Figure 24. Output Shift due to Solder Heat Effect shown in Figure 25. 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

Rev. L | Page 21 of 28
REF19x Series Data Sheet
management should still be exercised. A short, heavy, low dc integrator adjusts its output to establish the proper relationship
resistance (DCR) conductor should be used from U1 to 6 to the VOUT between the VOUT and GND references. Thus, any desired negative
Sense Point S, where the collector of Q1 connects to the load, Point F. output voltage can be selected by substituting for the appropriate
Because of the current limiting configuration, the dropout voltage reference IC. The sleep feature is maintained in the circuit with
circuit is raised about 1.1 V over that of the REF19x devices, due to the simple addition of a PNP transistor and a 10 kΩ resistor.
VS
the VBE of Q1 and the drop across Current Sense Resistor R4.
However, overall dropout is typically still low enough to allow 10kΩ
2N3906
operation of a 5 V to 3.3 V regulator/reference using the REF196 for SLEEP
2
TTL/CMOS
U1 as noted, with a VS as low as 4.5 V and a load current of 150 mA. VS
1kΩ 1µF
The requirement for a heat sink on Q1 depends on the maximum 3 SLEEP OUTPUT 6
+5V
input voltage and short-circuit current. With VS = 5 V and a REF19x
GND 100Ω
300 mA current limit, the worst-case dissipation of Q1 is 1.5 W, 4 1µF A1 –VREF
less than the TO-220 package 2 W limit. However, if smaller TO-39 10kΩ 100kΩ
or TO-5 package devices, such as the 2N4033, are used, the current –5V

00371-024
limit should be reduced to keep maximum dissipation below A1 = 1/2 OP295,
1/2 OP291
the package rating. This is accomplished by simply raising R4. Figure 26. Negative Precision Voltage Reference Uses No Precision Resistors
A tantalum output capacitor is used at C1 for its low equivalent One caveat to this approach is that although rail-to-rail output
series resistance (ESR), and the higher value is required for stability. amplifiers work best in the application, these operational amplifiers
Capacitor C2 provides input bypassing and can be an ordinary require a finite amount (mV) of headroom when required to provide
electrolytic. any load current; consider this issue when choosing the negative
Shutdown control of the booster stage is an option, and when used, supply for the circuit.
some cautions are needed. Due to the additional active devices STACKING REFERENCE ICs FOR ARBITRARY
in the VS line to U1, a direct drive to Pin 3 does not work as with an OUTPUTS
unbuffered REF19x device. To enable shutdown control, the Some applications may require two reference voltage sources that
connection from U1 to Q2 is broken at the X, and Diode D1 are a combined sum of standard outputs. The circuit in Figure 27
then allows a CMOS control source, VC, to drive U1 to 3 for on/off shows how this stacked output reference can be implemented.
operation. Startup from shutdown is not as clean under heavy Two reference ICs are used, fed from a common unregulated input,
load as it is in basic REF19x series, and can require several VS. The outputs of the individual ICs are connected in series, as
milliseconds under load. Nevertheless, it is still effective and shown in Figure 27, which provide two output voltages, VOUT1 and
can fully control 150 mA loads. When shutdown control is VOUT2. VOUT1 is the terminal voltage of U1, whereas VOUT2 is the
used, heavy capacitive loads should be minimized. sum of this voltage and the terminal voltage of U2. U1 and U2
NEGATIVE PRECISION REFERENCE WITHOUT are chosen for the two voltages that supply the required outputs
PRECISION RESISTORS (see Table 1). If, for example, both U1 and U2 are REF192s, the
In many current-output CMOS DAC applications where the output two outputs are 2.5 V and 5.0 V.
OUTPUT TABLE
signal voltage must be the same polarity as the reference voltage, it
U1/U2 VOUT1 (V) VOUT2 (V)
is often necessary to reconfigure a current-switching DAC into +VS REF192/REF192 2.5 5.0
a voltage-switching DAC using a 1.25 V reference, an op amp, VS > VOUT2 + 0.15V REF192/REF194 2.5 7.0
REF192/REF195 2.5 7.5
and a pair of resistors. Using a current-switching DAC directly 2

requires an additional operational amplifier at the output to U2

C1
0.1µF
3 REF19x 6 +VOUT2
reinvert the signal. A negative voltage reference is then desirable (SEE TABLE) +
4
VO (U2) C2
because an additional operational amplifier is not required for 1µF
either reinversion (current-switching mode) or amplification
(voltage-switching mode) of the DAC output voltage. In general, 2
any positive voltage reference can be converted into a negative C3
U1
3 REF19x 6 +VOUT1
voltage reference using an operational amplifier and a pair of 0.1µF (SEE TABLE)
+ C4 R1
VO (U1) 3.9kΩ
matched resistors in an inverting configuration. The disadvantage 4 1µF (SEE TEXT)
VIN
to this approach is that the largest single source of error in the COMMON
00371-025

VOUT
circuit is the relative matching of the resistors used. COMMON
The circuit illustrated in Figure 26 avoids the need for tightly Figure 27. Stacking Voltage References with the REF19x
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

Rev. L | Page 22 of 28
Data Sheet REF19x Series
VS
Although this concept is simple, some cautions are needed. Because
the lower reference circuit must sink a small bias current from U2
(50 μA to 100 μA), plus the base current from the series PNP output 2
transistor in U2, either the external load of U1 or R1 must provide VS

a path for this current. If the U1 minimum load is not well defined, REF19x
Resistor R1 should be used, set to a value that conservatively passes 3 SLEEP OUTPUT 6
1µF
600 μA of current with the applicable VOUT1 across it. Note that the GND R1
4
RSET
two U1 and U2 reference circuits are locally treated as macrocells, ISY
ADJUST P1
each having its own bypasses at input and output for best stability.
VIN ≥ IOUT × RL (MAX) + VSY (MIN) IOUT
Both U1 and U2 in this circuit can source dc currents up to
VOUT RL
their full rating. The minimum input voltage, VS, is determined by IOUT = + ISY (REF19x)
RSET
the sum of the outputs, VOUT2, plus the dropout voltage of U2. VOUT FOR EXAMPLE, REF195: VOUT = 5V
>> ISY IOUT = 5mA
A related variation on stacking two 3-terminal references is shown RSET

00371-027
R1 = 953Ω
in Figure 28, where U1, a REF192, is stacked with a 2-terminal P1 = 100Ω, 10-TURN

reference diode, such as the AD589. Like the 3-terminal stacked Figure 29. A Low Dropout, Precision Current Source
reference shown in Figure 27, this circuit provides two outputs, SWITCHED OUTPUT 5 V/3.3 V REFERENCE
VOUT1 and VOUT2, which are the individual terminal voltages of D1
and U1, respectively. Here this is 1.235 V and 2.5 V, which provides a Applications often require digital control of reference voltages,
VOUT2 of 3.735 V. When using 2-terminal reference diodes, such as selecting between one stable voltage and a second. With the
D1, the rated minimum and maximum device currents must be sleep feature inherent to the REF19x series, switched output
observed, and the maximum load current from VOUT1 can be no reference configurations are easily implemented with little
greater than the current setup by R1 and VO (U1). When VO additional hardware.
(U1) is equal to 2.5 V, R1 provides a 500 μA bias to D1, so the The circuit in Figure 30 shows the general technique, which takes
maximum load current available at VOUT1 is 450 μA or less. advantage of the output wire-OR capability of the REF19x device
+VS family. When off, a REF19x device is effectively an open circuit
VS > VOUT2 + 0.15V
at the output node with respect to the power supply. When on, a
2 REF19x device can source current up to its current rating, but
C1 3
U1
6 +VOUT2
sink only a few μA (essentially, just the relatively low current of the
0.1μF REF192 R1 3.735V
VO (U1)
+
C2 4.99kΩ
internal output scaling divider). Consequently, when two devices
4
1μF (SEE TEXT) are wired together at their common outputs, the output voltage
+VOUT1
is the same as the output voltage for the on device. The off state
+ C3 1.235V device draws a small standby current of 15 μA (maximum), but
D1 VO (D1)
AD589 1μF
VIN otherwise does not interfere with operation of the on device, which
COMMON
00371-026

VOUT can operate to its full current rating. Note that the two devices in
COMMON the circuit conveniently share both input and output capacitors,
Figure 28. Stacking Voltage References with the REF192
and with CMOS logic drive, it is power efficient.
PRECISION CURRENT SOURCE OUTPUT TABLE

In low power applications, the need often arises for a precision U1/U2 VC* VOUT (V)

current source that can operate on low supply voltages. As REF195/ HIGH 5.0
REF196 LOW 3.3
shown in Figure 29, any one of the devices in the REF19x family REF194/ HIGH 4.5
+VS = 6V REF195 LOW 5.0
of references can be configured as a precision current source.
2
*CMOS LOGIC LEVELS
The circuit configuration illustrated is a floating current source U1
1 2 3 4
with a grounded load. The output voltage of the reference is VC 3 REF19x 6
(SEE TABLE)
U3A U3B
bootstrapped across RSET, which sets the output current into the 74HC04 74HC04 4

load. With this configuration, circuit precision is maintained for +VOUT

load currents in the range from the reference’s supply current

2
(typically 30 μA) to approximately 30 mA. The low dropout U2 + C2
voltage of these devices maximizes the current source’s output 3 REF19x 6 1µF
(SEE TABLE)
voltage compliance without excess headroom. C1 4
0.1µF
00371-028

VIN
COMMON VOUT
COMMON

Figure 30. Switched Output Reference

Rev. L | Page 23 of 28
REF19x Series Data Sheet
VS
Using dissimilar REF19x series devices with this configuration VS
RLW
allows logic selection between the U1/U2-specified terminal 2
+VOUT
SENSE
voltages. For example, with U1 (a REF195) and U2 (a REF196), VS 2
RLW
1 +VOUT
as noted in the table in Figure 30, changing the CMOS-compatible A1
3 FORCE
SLEEP 3 OUTPUT 6
VC logic control voltage from high to low selects between a nominal REF19x
GND A1 = 1/2 OP295
output of 5.0 V and 3.3 V, and vice versa. Other REF19x family

00371-029
4 1µF 100kΩ 1/2 OP292 RL
units can also be used for U1/U2, with similar operation in a OP183

logic sense, but with outputs as per the individual paired devices Figure 31. Low Dropout, Kelvin-Connected Voltage Reference
(see the table in Figure 30). Of course, the exact output voltage
tolerance, drift, and overall quality of the reference voltage is FAIL-SAFE 5 V REFERENCE
consistent with the grade of individual U1 and U2 devices. Some critical applications require a reference voltage to be
maintained at a constant voltage, even with a loss of primary
Due to the nature of the wire-OR, one application caveat should
power. The low standby power of the REF19x series and the
be understood about this circuit. Because U1 and U2 can only
switched output capability allow a fail-safe reference con-
source current effectively, negative going output voltage changes,
figuration to be implemented rather easily. This reference
which require the sinking of current, necessarily take longer than
maintains a tight output voltage tolerance for either a primary
positive going changes. In practice, this means that the circuit is
power source (ac line derived) or a standby (battery derived)
quite fast when undergoing a transition from 3.3 V to 5 V, but the
power source, automatically switching between the two as the
transition from 5 V to 3.3 V takes longer. Exactly how much
power conditions change.
longer is a function of the load resistance, RL, seen at the output and
the typical 1 μF value of C2. In general, a conservative transition The circuit in Figure 32 illustrates this concept, which borrows
time is approximately several milliseconds for load resistances from the switched output idea of Figure 30, again using the
in the range of 100 Ω to 1 kΩ. Note that for highest accuracy at REF19x device family output wire-OR capability. In this case,
the new output voltage, several time constants should be allowed because a constant 5 V reference voltage is desired for all condi-
(for example, >7.6 time constants for <1/2 LSB error @ 10 bits). tions, two REF195 devices are used for U1 and U2, with their
on/off switching controlled by the presence or absence of the
KELVIN CONNECTIONS primary dc supply source, VS. VBAT is a 6 V battery backup
In many portable applications where the PCB cost and area go source that supplies power to the load only when VS fails. For
hand-in-hand, circuit interconnects are very often narrow. These normal (VS present) power conditions, VBAT sees only the 15 μA
narrow lines can cause large voltage drops if the voltage reference is (maximum) standby current drain of U1 in its off state.
required to provide load currents to various functions. The inter- In operation, it is assumed that for all conditions, either U1 or
connections of a circuit can exhibit a typical line resistance of U2 is on, and a 5 V reference output is available. With this
0.45 mΩ/square (for example, 1 oz. Cu). voltage constant, a scaled down version is applied to the
In applications where these devices are configured as low dropout Comparator IC U3, providing a fixed 0.5 V input to the negative
voltage regulators, these wiring voltage drops can become a large input for all power conditions. The R1 to R2 divider provides a
source of error. To circumvent this problem, force and sense signal to the U3 positive input proportionally to VS, which
connections can be made to the reference through the use of an switches U3 and U1/U2, dependent upon the absolute level of
operational amplifier, as shown in Figure 31. This method provides VS. In Figure 32, Op Amp U3 is configured as a comparator
a means by which the effects of wiring resistance voltage drops can with hysteresis, which provides clean, noise-free output
be eliminated. Load currents flowing through wiring resistance switching. This hysteresis is important to eliminate rapid
produce an I-R error (ILOAD × RWIRE) at the load. However, the switching at the threshold due to VS ripple. Furthermore, the
Kelvin connection overcomes the problem by including the device chosen is the AD820, a rail-to-rail output device. This
wiring resistance within the forcing loop of the op amp. Because device provides high and low output states within a few mV of
the op amp senses the load voltage, op amp loop control forces VS, ground for accurate thresholds, and compatible drive for U2
the output to compensate for the wiring error and to produce for all VS conditions. R3 provides positive feedback for circuit
the correct voltage at the load. Depending on the reference hysteresis, changing the threshold at the positive input as a
device chosen, operational amplifiers that can be used in this function of the output of U3.
application are the OP295, OP292, and OP183.

Rev. L | Page 24 of 28
Data Sheet REF19x Series
+VBAT
2
+VS C2
0.1µF U1
R1
1.1MΩ R3 R6 3 REF195 6
10MΩ 100Ω Q1 (SEE TABLE)
2N3904 5.000V
4
C1
3 + 7 0.1µF
6
2 – 4 U3 2
AD820 + C3
U2
R2
3 REF195 6 1µF
(SEE TABLE)
100kΩ
R4 4
900kΩ
C4 R5
VS, VBAT 0.1µF 100kΩ

00371-030
VOUT
COMMON COMMON

Figure 32. Fail-Safe 5 V Reference

For VS levels lower than the lower threshold, the output of U3 is 100Ω

low, thus U2 and Q1 are off and U1 is on. For VS levels higher REF195 10μF
than the upper threshold, the situation reverses, with U1 off and 2 6

both U2 and Q1 on. In the interest of battery power conserva- + +

10μF 4 1μF
tion, all of the comparison switching circuitry is powered from
VS and is arranged so that when VS fails, the default output 57kΩ
0.1μF
1%
comes from U1.
For the R1 to R3 values, as shown in Figure 32, lower/upper VS 3 + 4

switching thresholds are approximately 5.5 V and 6 V, respec- 1/4 1 2N2222

OP492
tively. These can be changed to suit other VS supplies, as can the 0.1μF
10kΩ 2 – 11
1%
REF19x devices used for U1 and U2, over a range of 2.5 V to
5 V of output. U3 can operate down to a VS of 3.3 V, which is 500Ω
generally compatible with all REF19x family devices. 0.1%

LOW POWER, STRAIN GAGE CIRCUIT

10kΩ
As shown in Figure 33, the REF19x family of references can be 1% 0.01μF

used in conjunction with low supply voltage operational ampli- 20kΩ

1%
fiers, such as the OP492 or the OP747, in a self-contained strain 20kΩ
13 –
gage circuit in which the REF195 is used as the core. Other 1/4
14
1%
6 –
references can be easily accommodated by changing circuit OP492 1/4
12 + 7 OUTPUT
OP492
element values. The references play a dual role, first as the 2.21kΩ 10kΩ 5 +
1%
voltage regulator to provide the supply voltage requirements of
the strain gage and the operational amplifiers, and second as a
9 – 20kΩ
precision voltage reference for the current source used to 1/4 1%
8
stimulate the bridge. A distinct feature of the circuit is that it OP492 20kΩ

00371-031
10 + 1%
can be remotely controlled on or off by digital means via
the SLEEP pin. Figure 33. Low Power, Strain Gage Circuit

Rev. L | Page 25 of 28
REF19x Series Data Sheet

OUTLINE DIMENSIONS
0.400 (10.16)
0.365 (9.27)
0.355 (9.02)

8 5 0.280 (7.11)
0.250 (6.35)
1 0.240 (6.10)
4
0.325 (8.26)
0.310 (7.87)
0.100 (2.54) 0.300 (7.62)
BSC 0.060 (1.52) 0.195 (4.95)
0.210 (5.33) MAX 0.130 (3.30)
MAX 0.115 (2.92)
0.015
0.150 (3.81) (0.38) 0.015 (0.38)
0.130 (3.30) MIN GAUGE
0.115 (2.92) PLANE 0.014 (0.36)
SEATING
PLANE 0.010 (0.25)
0.022 (0.56) 0.008 (0.20)
0.005 (0.13) 0.430 (10.92)
0.018 (0.46) MIN MAX
0.014 (0.36)

0.070 (1.78)
0.060 (1.52)
0.045 (1.14)

COMPLIANT TO JEDEC STANDARDS MS-001

CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR

070606-A
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
CORNER LEADS MAY BE CONFIGURED AS WHOLE OR HALF LEADS.

Figure 34. 8-Lead Plastic Dual In-Line Package [PDIP]

P-Suffix (N-8)
Dimensions shown in inches and (millimeters)

3.10 5.00 (0.1968)

3.00 4.80 (0.1890)
2.90

8 5
4.00 (0.1574) 6.20 (0.2441)
8 5
3.80 (0.1497) 1 5.80 (0.2284)
4
4.50
4.40 6.40 BSC
4.30
1.27 (0.0500) 0.50 (0.0196)
BSC 45°
1 4 1.75 (0.0688) 0.25 (0.0099)
0.25 (0.0098) 1.35 (0.0532)
8°
PIN 1 0.10 (0.0040) 0°
0.65 BSC COPLANARITY 0.51 (0.0201)
0.10 1.27 (0.0500)
0.15 0.31 (0.0122) 0.25 (0.0098)
1.20 SEATING 0.40 (0.0157)
0.05 MAX PLANE 0.17 (0.0067)
8°
0.30 0° 0.75
COPLANARITY SEATING 0.20 COMPLIANT TO JEDEC STANDARDS MS-012-AA
0.10 0.19 PLANE 0.60
0.09 CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
0.45
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
COMPLIANT TO JEDEC STANDARDS MO-153-AA REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 35. 8-Lead Thin Shrink Small Outline Package [TSSOP] Figure 36. 8-Lead Standard Small Outline Package [SOIC_N]
(RU-8) Narrow Body
Dimensions shown in millimeters S-Suffix (R-8)
Dimensions shown in millimeters and (inches)

Rev. L | Page 26 of 28
Data Sheet REF19x Series
ORDERING GUIDE
Model 1 Temperature Range Package Description Package Option Ordering Quantity
REF191ES −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF191ES-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF191ESZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF191ESZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF191GS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF191GS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF191GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF191GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192ES −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192ES-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192ES-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF192ESZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192ESZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192ESZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF192FS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192FS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192FS-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF192FSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192FSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192FSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF192GPZ −40°C to +85°C 8-Lead PDIP P-Suffix (N-8)
REF192GRUZ −40°C to +85°C 8-Lead TSSOP RU-8
REF192GRUZ-REEL7 −40°C to +85°C 8-Lead TSSOP RU-8 1,000
REF192GS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192GS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192GS-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF192GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF192GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF192GSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF193GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF193GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF194ES −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF194ESZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF194ESZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF194GS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF194GS-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF194GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF194GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF194GSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF195ES −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195ES-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195ESZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195ESZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195FS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195FS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195FSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195FSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195GPZ −40°C to +85°C 8-Lead PDIP P-Suffix (N-8)
REF195GRU-REEL7 −40°C to +85°C 8-Lead TSSOP RU-8 1,000
REF195GRUZ −40°C to +85°C 8-Lead TSSOP RU-8
REF195GRUZ-REEL7 −40°C to +85°C 8-Lead TSSOP RU-8 1,000

Rev. L | Page 27 of 28
REF19x Series Data Sheet
Model 1 Temperature Range Package Description Package Option Ordering Quantity
REF195GS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195GS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195GS-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF195GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF195GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF195GSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF196GRUZ-REEL7 −40°C to +85°C 8-Lead TSSOP RU-8 1,000
REF196GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF196GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF196GSZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF198ES −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF198ES-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF198ESZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF198ESZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF198ESZ-REEL7 −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 1,000
REF198FS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF198FSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF198FSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF198GRUZ −40°C to +85°C 8-Lead TSSOP RU-8
REF198GRUZ-REEL7 −40°C to +85°C 8-Lead TSSOP RU-8 2,500
REF198GS −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF198GS-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
REF198GSZ −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8)
REF198GSZ-REEL −40°C to +85°C 8-Lead SOIC_N S-Suffix (R-8) 2,500
1
Z = RoHS Compliant Part.

©1996–2011 Analog Devices, Inc. All rights reserved. Trademarks and

registered trademarks are the property of their respective owners.
D00371-0-9/11(L)

Rev. L | Page 28 of 28