MAXIM MAX6126 Technical data

General Description

The MAX6126 is an ultra-low-noise, high-precision, low­dropout voltage reference. This family of voltage refer­ences feature curvature-correction circuitry and
high-stability, laser-trimmed, thin-film resistors that
result in 3ppm/°C (max) temperature coefficients and
an excellent ±0.02% (max) initial accuracy. The propri­etary low-noise reference architecture produces a low
flicker noise of 1.3µV

P-P

and wideband noise as low as

60nV/√Hz (2.048V output) without the increased supply
current usually found in low-noise references. Improve
wideband noise to 35nV/√Hz and AC power-supply
rejection by adding a 0.1µF capacitor at the noise
reduction pin. The MAX6126 series mode reference
operates from a wide 2.7V to 12.6V supply voltage
range and load-regulation specifications are guaran­teed to be less than 0.025Ω for sink and source cur­rents up to 10mA. These devices are available over the
automotive temperature range of -40°C to +125°C.

The MAX6126 typically draws 380µA of supply current
and is available in 2.048V, 2.500V, 2.800V, 3.000V,

4.096V, and 5.000V output voltages. These devices
also feature dropout voltages as low as 200mV. Unlike
conventional shunt-mode (two-terminal) references that
waste supply current and require an external resistor,
the MAX6126 offers supply current that is virtually inde­pendent of supply voltage and does not require an
external resistor. The MAX6126 is stable with 0.1µF to
10µF of load capacitance.

The MAX6126 is available in the tiny 8-pin µMAX®, as
well as 8-pin SO packages.

Applications

High-Resolution A/D and D/A Converters

ATE Equipment

High-Accuracy Reference Standard

Precision Current Sources

Digital Voltmeters

High-Accuracy Industrial and Process Control

Features

o Ultra-Low 1.3µV

P-P

Noise (0.1Hz to 10Hz, 2.048V

Output)

o Ultra-Low 3ppm/°C (max) Temperature Coefficient

o ±0.02% (max) Initial Accuracy

o Wide (V

OUT

+ 200mV) to 12.6V Supply Voltage

Range

o Low 200mV (max) Dropout Voltage

o 380µA Quiescent Supply Current

o 10mA Sink/Source-Current Capability

o Stable with C

LOAD

= 0.1µF to 10µF

o Low 20ppm/1000hr Long-Term Stability

o 0.025Ω (max) Load Regulation

o 20µV/V (max) Line Regulation

o Force and Sense Outputs for Remote Sensing

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

________________________________________________________________

Maxim Integrated Products

1

Pin Configuration

Ordering Information

19-2647; Rev 5; 12/10

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

Ordering Information continued at end of data sheet.

µMAX is a registered trademark of Maxim Integrated Products, Inc.

+

Denotes a lead(Pb)-free/RoHS-compliant package.

TOP VIEW

NR

GND

*I.C. = INTERNALLY CONNECTED. DO NOT USE.

+

1

2

MAX6126

3

4

SO/µMAX

8

I.C.*

7

OUTFIN

OUTS

6

I.C.*GNDS

5

PART TEMP RANGE

MAX6126AASA21+ -40°C to +125°C 8 SO 2.048 0.02 3 —
MAX6126BASA21+ -40°C to +125°C 8 SO 2.048 0.06 5 —
MAX6126A21+ -40°C to +125°C 8 µMAX 2.048 0.06 3 6126A21

PIN­PACKAGE

OUTPUT

VOLTAGE

(V)

MAXIMUM INITIAL

ACCURACY (%)

MAXIMUM TEMPCO

(-40°C to +85°C)

(ppm/°C)

TOP

MARK

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

(All voltages referenced to GND)

GNDS ....................................................................-0.3V to +0.3V

IN ........................................................................... -0.3V to +13V

OUTF, OUTS, NR........ -0.3V to the lesser of (V

IN

+ 0.3V) or +6V

Output Short Circuit to GND or IN ..........................................60s

Continuous Power Dissipation (T

A

= +70°C)

8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW

8-Pin SO (derate 5.88mW/°C above +70°C) ...............471mW

Operating Temperature Range ........................-40°C to +125°C

Junction Temperature .....................................................+150°C

Storage Temperature Range ............................-65°C to +150°C

Lead Temperature (soldering, 10s) ................................+300°C

Soldering Temperature (reflow) ......................................+260°C

ELECTRICAL CHARACTERISTICS—MAX6126_21 (V

OUT

= 2.048V)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

OUTPUT

Output Voltage V

Output Voltage Accuracy

Output Voltage Temperature
Coefficient (Note 1)

Line Regulation

Load Regulation

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2)

Long-Term Stability

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

T

OUT

= +25°C 2.048 V

A

A grade SO -0.02 +0.02

Referred to
V

,

OUT

= +25°C

T

A

B grade SO -0.06 +0.06

A grade µMAX -0.06 +0.06

B grade µMAX -0.1 +0.1

A grade SO 0.5 3

B grade SO 1 5

A grade µMAX 1 3

B grade µMAX 2 7

A grade SO 1 5

B grade SO 2 10

A grade µMAX 2 5

TCV

OUT

T

= -40°C

A

to +85°C

T

= -40°C

A

to +125°C

B grade µMAX 3 12

T

= +25°C220

∆V

/

OUT

∆V

∆V

OUT

∆I

OUT Sinking: -10mA ≤ I

SC

∆V

OUT

cycle

∆V

OUT

time

2.7V ≤ VIN ≤

12.6V

IN

Sourcing: 0 ≤ I

/

Short to GND 160

Short to IN 20

SO 25

/

µMAX 80

/

1000hr at T

A

= -40°C to +125°C40

T

A

≤ 10mA 0.7 25

OUT

≤ 0 1.3 25

OUT

= +25°C

A

SO 20

µMAX 100

%

ppm/°C

µV/V

µV/mA

mA

ppm

ppm/

1000hr

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS—MAX6126_21 (V

OUT

= 2.048V) (continued)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

ELECTRICAL CHARACTERISTICS—MAX6126_25 (V

OUT

= 2.500V)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

DYNAMIC CHARACTERISTICS

Noise Voltage e

Turn-On Settling Time t

Capacitive-Load Stability Range C

INPUT

Supply Voltage Range V

Quiescent Supply Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUT

R

LOAD

IN

IN

f = 0.1Hz to 10Hz 1.3 µV

f = 1kHz, CNR = 0 60

f = 1kHz, CNR = 0.1µF 35

To V
final value

No sustained oscillations 0.1 to 10 µF

Guaranteed by line-regulation test 2.7 12.6 V

T

T

= 0.01% of

OUT

= +25°C 380 550

A

= -40°C to +125°C 725

A

OUTPUT

Output Voltage V

Output Voltage Accuracy

Output Voltage Temperature
Coefficient (Note 1)

Line Regulation

Load Regulation

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

TCV

∆V

∆V

∆V

∆I

OUT

OUT

/

OUT

IN

/

OUT
OUT Sinking: -10mA ≤ I

TA = +25°C 2.500 V

Referred to V
T

= +25°C

A

TA = -40°C to +85°C

TA = -40°C to
+125°C

2.7V ≤ VIN ≤ 12.6V

Sourcing: 0 ≤ I

OUT

OUT

A grade SO -0.02 +0.02

B grade SO -0.06 +0.06

,

A grade µMAX -0.06 +0.06

B grade µMAX -0.1 +0.1

A grade SO 0.5 3

B grade SO 1 5

A grade µMAX 1 3

B grade µMAX 2 7

A grade SO 1 5

B grade SO 2 10

A grade µMAX 2 5

B grade µMAX 3 12

TA = +25°C320

T

= -40°C to +125°C40

A

≤ 10mA 1 25

≤ 0 1.8 25

OUT

CNR = 0 0.8

C

= 0.1µF 20

NR

P-P

nV/√Hz

ms

µA

%

ppm/°C

µV/V

µV/mA

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS—MAX6126_25 (V

OUT

= 2.500V) (continued)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

ELECTRICAL CHARACTERISTICS—MAX6126_28 (V

OUT

= 2.800V)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Dropout Voltage (Note 3) VIN - V

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2)

Long-Term Stability

DYNAMIC CHARACTERISTICS

Turn-On Settling Time t

Capacitive-Load Stability Range C

INPUT

Supply Voltage Range V

Quiescent Supply Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

∆V

cycle

∆V

time

OUT∆VOUT

SC

/

OUT

/

OUT

OUT

R

LOAD

IN

IN

= 0.1%

Short to GND 160

Short to IN 20

SO 35

µMAX 80

1000hr at T

f = 0.1Hz to 10Hz 1.45 µV

f = 1kHz, CNR = 0 75Noise Voltage e

f = 1kHz, CNR = 0.1µF 45

To V

OUT

final value

No sustained oscillations 0.1 to 10 µF

Guaranteed by line-regulation test 2.7 12.6 V

TA = +25°C 380 550

TA = -40°C to +125°C 725

= +25°C

A

= 0.01% of

I

= 5mA 0.06 0.2

OUT

I

= 10mA 0.12 0.4

OUT

SO 20

µMAX 100

CNR = 0 1

C

= 0.1µF 20

NR

V

mA

ppm

ppm/

1000hr

P-P

nV/√Hz

ms

µA

OUTPUT

Output Voltage V

Output Voltage Accuracy

Output Voltage Temperature
Coefficient (Note 1)

Line Regulation ∆V

Load Regulation ∆V

Dropout Voltage (Note 3) VIN - V

PARAMETER SYMBOL CONDTIONS MIN TYP MAX UNITS

TCV

OUT

OUT

/∆VIN3.0V ≤ VIN ≤ 12.6V

OUT

/∆V

OUT

OUT

TA = +25°C 2.800 V

Referred to VOUT, T
+25°C

TA = -40°C to +85°C

TA = -40°C to +125°C

Sourcing: 0 ≤ I

IN

Sinking: -10mA ≤ I

∆V

= 0.1%

OUT

=

A

≤ 10mA 1.3 28

OUT

≤ 0 2.4 28

OUT

A grade µMAX -0.06 +0.06

B grade µMAX -0.10 +0.10

A grade µMAX 1 3

B grade µMAX 2 7

A grade µMAX 2 5

B grade µMAX 3 12

TA = +25°C 3.5 23

= -40°C to

T

A

+125°C

I

= 5mA 0.06 0.2

OUT

= 10mA 0.12 0.4

I

OUT

45

%

ppm/°C

µV/V

µV/mA

V

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS—MAX6126_28 (V

OUT

= 2.800V) (continued)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

ELECTRICAL CHARACTERISTICS—MAX6126_30 (V

OUT

= 3.000V)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2) ∆V

Long-Term Stability ∆V

DYNAMIC CHARACTERISTICS

Noise Voltage e

Turn-On Settling Time t

Capacitive-Load Stability Range C

INPUT

Supply Voltage Range V

Quiescent Supply Current I

PARAMETER SYMBOL CONDTIONS MIN TYP MAX UNITS

OUT

SC

/cycle µMAX 80 ppm

/time 1000hr at TA = +25°C µMAX 100

OUT

OUT

R

LOAD

IN

IN

Short to GND 160

Short to IN 20

f = 0.1Hz to 10Hz 1.45 µV

f = 1kHz, CNR = 0 75

f = 1kHz, CNR = 0.1µF 45

To V
final value

No sustained oscillations 0.1 to 10 µF

Guaranteed by line-regulation test 3.0 12.6 V

TA = +25°C 380 550

TA = -40°C to +125°C 725

= 0.01% of

OUT

CNR = 0 1

= 0.1µF 20

C

NR

mA

ppm/

1000hr

P-P

nV/√Hz

ms

µA

OUTPUT

Output Voltage V

Output Voltage Accuracy

Output Voltage Temperature
Coefficient (Note 1)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

TCV

OUT

OUT

TA = +25°C 3.000 V

A grade SO -0.02 +0.02

Referred to V
T

= +25°C

A

TA = -40°C to
+85°C

TA = -40°C to
+125°C

OUT

B grade SO -0.06 +0.06

,

A grade µMAX -0.06 +0.06

B grade µMAX -0.1 +0.1

A grade SO 0.5 3

B grade SO 1 5

A grade µMAX 1 3

B grade µMAX 2 7

A grade SO 1 5

B grade SO 2 10

A grade µMAX 2 5

B grade µMAX 3 12

%

ppm/°C

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

6 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS—MAX6126_30 (V

OUT

= 3.000V) (continued)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

ELECTRICAL CHARACTERISTICS—MAX6126_41 (V

OUT

= 4.096V)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Line Regulation

Load Regulation

Dropout Voltage (Note 3) VIN - V

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2)

Long-Term Stability

DYNAMIC CHARACTERISTICS

Noise Voltage e

Capacitive-Load Stability Range C

Turn-On Settling Time t

INPUT

Supply Voltage Range V

Quiescent Supply Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

∆V

∆V

∆I

∆V

cycle

∆V

/

OUT

∆V

IN

/

OUT

OUT

OUT∆VOUT

SC

/

OUT

/

OUT

time

OUT

LOAD

R

IN

IN

3.2V ≤ VIN ≤ 12.6V

Sourcing: 0 ≤ I
Sinking: -10mA ≤ I

Short to GND 160

Short to IN 20

SO 20

µMAX 80

1000hr at T

f = 0.1Hz to 10Hz 1.75 µV

f = 1kHz, CNR = 0 90

f = 1kHz, CNR = 0.1µF 55

No sustained oscillations 0.1 to 10 µF

To V

OUT

of final value

Guaranteed by line-regulation test 3.2 12.6 V

TA = +25°C 380 550

TA = -40°C to +125°C 725

= 0.1%

A

= 0.01%

OUT

= +25°C

TA = +25°C425

= -40°C to +125°C50

T

A

≤ 10mA 1.5 30

≤ 0 2.8 30

OUT

I

= 5mA 0.06 0.2

OUT

I

= 10mA 0.11 0.4

OUT

SO 20

µMAX 100

CNR = 0 1.2

= 0.1µF 20

C

NR

µV/V

µV/mA

V

mA

ppm

ppm/

1000hr

P-P

nV/√Hz

ms

µA

OUTPUT

Output Voltage V

Output Voltage Accuracy

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUT

TA = +25°C 4.096 V

A grade SO -0.02 +0.02

Referred to V
T

= +25°C

A

OUT

B grade SO -0.06 +0.06

,

A grade µMAX -0.06 +0.06

B grade µMAX -0.1 +0.1

%

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

_______________________________________________________________________________________ 7

ELECTRICAL CHARACTERISTICS—MAX6126_41 (V

OUT

= 4.096V) (continued)

(VIN= 5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Output Voltage Temperature
Coefficient (Note 1)

Line Regulation

Load Regulation

Dropout Voltage (Note 3) VIN - V

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2)

Long-Term Stability

DYNAMIC CHARACTERISTICS

Capacitive-Load Stability Range C

Turn-On Settling Time t

INPUT

Supply Voltage Range V

Quiescent Supply Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

TCV

∆V

∆V

∆I

∆V

cycle

∆V

OUT

/

OUT

∆V

IN

/

OUT
OUT Sinking: -10mA ≤ I

OUT∆VOUT

SC

/

OUT

/

OUT

time

OUT

LOAD

R

IN

IN

TA = -40°C to
+85°C

TA = -40°C to
+125°C

4.3V ≤ VIN ≤ 12.6V

Sourcing: 0 ≤ I

= 0.1%

Short to GND 160

Short to IN 20

SO 20

µMAX 80

1000hr at T

f = 0.1Hz to 10Hz 2.4 µV

f = 1kHz, CNR = 0 120Noise Voltage e

f = 1kHz, CNR = 0.1µF 80

No sustained oscillations 0.1 to 10 µF

To V
final value

Guaranteed by line-regulation test 4.3 12.6 V

TA = +25°C 380 550

TA = -40°C to +125°C 725

= 0.01% of

OUT

= + 25°C

A

A grade SO 0.5 3

B grade SO 1 5

A grade µMAX 1 3

B grade µMAX 2 7

A grade SO 1 5

B grade SO 2 10

A grade µMAX 2 5

B grade µMAX 3 12

TA = +25°C 4.5 30

T

= -40°C to +125°C60

A

≤ 10mA 2 40

OUT

≤ 0 5 40

OUT

I

OUT

I

OUT

SO 20

µMAX 100

CNR = 0 1.6

C

NR

= 5mA 0.05 0.2

= 10mA 0.1 0.4

= 0.1µF 20

ppm/°C

µV/V

µV/mA

V

mA

ppm

ppm/

1000hr

P-P

nV/√Hz

ms

µA

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

8 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS—MAX6126_50 (V

OUT

= 5.000V)

(VIN= 5.5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

OUTPUT

Output Voltage V

Output Voltage Accuracy TA = +25°C

OUT

TA = +25°C 5.000 V

TA = -40°C to +85°C

Output Voltage Temperature
Coefficient (Note 1)

Line Regulation

Load Regulation

Dropout Voltage (Note 3) VIN - V

OUT Short-Circuit Current I

Thermal Hysteresis (Note 2)

Long-Term Stability

DYNAMIC CHARACTERISTICS

Capacitive-Load Stability Range C

TCV

OUT

TA = -40°C to
+125°C

∆V

/

OUT

∆V

∆V

OUT

∆I

OUT Sinking: -10mA ≤ I

SC

∆V

OUT

cycle

∆V

OUT

time

OUT

LOAD

5.2V ≤ VIN ≤ 12.6V

IN

Sourcing: 0 ≤ I

/

OUT∆VOUT

/

/

= 0.1%

Short to GND 160

Short to IN 20

SO 15

µMAX 80

1000hr at T

f = 0.1Hz to 10Hz 2.85 µV

f = 1kHz, CNR = 0 145Noise Voltage e

f = 1kHz, CNR = 0.1µF 95

No sustained oscillations 0.1 to 10 µF

OUT

= +25°C

A

A grade SO -0.02 +0.02

B grade SO -0.06 +0.06

A grade µMAX -0.06 +0.06

B grade µMAX -0.1 +0.1

A grade SO 0.5 3

B grade SO 1 5

A grade µMAX 1 3

B grade µMAX 2 7

A grade SO 1 5

B grade SO 2 10

A grade µMAX 2 5

B grade µMAX 3 12

TA = +25°C340

T

= -40°C to +125°C80

A

≤ 10mA 2.5 50

≤ 0 6.5 50

OUT

I

= 5mA 0.05 0.2

OUT

= 10mA 0.1 0.4

I

OUT

SO 20

µMAX 100

%

ppm/°C

µV/V

µV/mA

V

mA

ppm

ppm/

1000hr

P-P

nV/√Hz

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

_______________________________________________________________________________________ 9

ELECTRICAL CHARACTERISTICS—MAX6126_50 (V

OUT

= 5.000V) (continued)

(VIN= 5.5V, C

LOAD

= 0.1µF, I

OUT

= 0, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Note 1: Temperature coefficient is measured by the “box” method, i.e., the maximum ∆V

OUT

/ V

OUT

is divided by the maximum ∆T.

Note 2: Thermal hysteresis is defined as the change in +25°C output voltage before and after cycling the device from T

MAX

to T

MIN

.

Note 3: Dropout voltage is defined as the minimum differential voltage (V

IN

- V

OUT

) at which V

OUT

decreases by 0.1% from its

original value at V

IN

= 5.0V (VIN= 5.5V for V

OUT

= 5.0V).

Typical Operating Characteristics

(VIN= 5V for MAX6126_21/25/30/41, VIN= 5.5V for MAX6126_50, C

LOAD

= 0.1µF, I

OUT

= 0, TA= +25°C, unless otherwise specified.)

(Note 5)

MAX6126A_21

OUTPUT VOLTAGE TEMPERATURE DRIFT

(V

OUT

= 2.048V) (SO)

MAX6126 toc01

TEMPERATURE (°C)

OUTPUT VOLTAGE (V)

1007550250-25

2.0465

2.0470

2.0475

2.0480

2.0485

2.0490

2.0460

-50 125

THREE TYPICAL PARTS

MAX6126A_21

OUTPUT VOLTAGE TEMPERATURE DRIFT

(V

OUT

= 2.048V) (µMAX)

MAX6126 toc02

TEMPERATURE (°C)

OUTPUT VOLTAGE (V)

1007550250-25

2.0480

2.0475

2.0485

2.0490

2.0470

-50 125

THREE TYPICAL PARTS

MAX6126A_50

OUTPUT VOLTAGE TEMPERATURE DRIFT

(V

OUT

= 5.000V) (SO)

MAX6126 toc03

TEMPERATURE (°C)

OUTPUT VOLTAGE (V)

1007550250-25

5.000

4.999

5.001

5.002

4.998

-50 125

THREE TYPICAL PARTS

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Turn-On Settling Time t

R

To V

OUT

final value

= 0.01% of

CNR = 0 2

C

NR

= 0.1µF 20

INPUT

Supply Voltage Range V

Quiescent Supply Current I

IN

Guaranteed by line-regulation test 5.2 12.6 V

IN

TA = +25°C 380 550

TA = -40°C to +125°C 725

ms

µA

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

10 ______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VIN= 5V for MAX6126_21/25/30/41, VIN= 5.5V for MAX6126_50, C

LOAD

= 0.1µF, I

OUT

= 0, TA= +25°C, unless otherwise specified.)

(Note 5)

MAX6126A_50

OUTPUT VOLTAGE TEMPERATURE DRIFT

(V

OUT

= 5.000V) (µMAX)

MAX6126 toc04

TEMPERATURE (°C)

OUTPUT VOLTAGE (V)

1007550250-25

5.000

4.999

5.001

5.002

4.998

-50 125

THREE TYPICAL PARTS

MAX6126_21

LOAD REGULATION

MAX6126 toc05

OUTPUT CURRENT (mA)

OUTPUT VOLTAGE (V)

50-5

2.0465

2.0470

2.0475

2.0480

2.0485

2.0460

-10 10

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_50

LOAD REGULATION

MAX6126 toc06

OUTPUT CURRENT (mA)

OUTPUT VOLTAGE (V)

50-5

4.997

4.998

4.999

5.000

5.001

4.996

-10 10

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_50

POWER-SUPPLY REJECTION RATIO

vs. FREQUENCY

MAX6126 toc10

FREQUENCY (kHz)

PSRR (dB)

1001010.10.01

-100

-80

-60

-40

-20

0

-120

0.001 1000

MAX6126_21

SUPPLY CURRENT vs. INPUT VOLTAGE

MAX6126 toc11

INPUT VOLTAGE (V)

SUPPLY CURRENT (µA)

12108642

100

200

300

400

500

600

0

014

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_50

SUPPLY CURRENT vs. INPUT VOLTAGE

MAX6126 toc12

INPUT VOLTAGE (V)

SUPPLY CURRENT (µA)

12106 842

100

200

300

400

500

600

700

800

900

0

014

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_25

DROPOUT VOLTAGE

vs. SOURCE CURRENT

MAX6126 toc07

SOURCE CURRENT (mA)

DROPOUT VOLTAGE (mV)

12963

50

100

150

200

250

300

0

015

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_50

DROPOUT VOLTAGE

vs. SOURCE CURRENT

MAX6126 toc08

SOURCE CURRENT (mA)

DROPOUT VOLTAGE (mV)

12963

50

100

150

200

250

0

015

TA = +25°C

TA = -40°C

TA = +125°C

MAX6126_21

POWER-SUPPLY REJECTION RATIO

vs. FREQUENCY

MAX6126 toc09

FREQUENCY (kHz)

PSRR (dB)

1001010.10.01

-100

-80

-60

-40

-20

0

-120

0.001 1000

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

______________________________________________________________________________________

11

Typical Operating Characteristics (continued)

(VIN= 5V for MAX6126_21/25/30/41, VIN= 5.5V for MAX6126_50, C

LOAD

= 0.1µF, I

OUT

= 0, TA= +25°C, unless otherwise specified.)

(Note 5)

MAX6126_21

OUTPUT NOISE (0.1Hz TO 10Hz)

MAX6126 toc13

1s/div

0.4µV/div

V

OUT

= 2.048V

MAX6126_50

OUTPUT NOISE (0.1Hz TO 10Hz)

MAX6126 toc14

1s/div

1µV/div

V

OUT

= 5V

MAX6126_21

LOAD TRANSIENT

MAX6126 toc15

200µs/div

0mA

10mA

V

OUT

AC-COUPLED
100mV/div

C

LOAD

= 0.1µF

V

IN

= 5V

I

OUT

5mA/div

I

OUT

= 0 TO 10mA

V

OUT

= 2.048V

MAX6126_21

LOAD TRANSIENT

MAX6126 toc16

200µs/div

C

LOAD

= 0.1µF

V

IN

= 5V

I

OUT

= -100µA TO 1mA

V

OUT

= 2.048V

-100µA

1mA

V

OUT

AC-COUPLED
20mV/div

I

OUT

500µA/div

MAX6126_21

LOAD TRANSIENT

MAX6126 toc17

400µs/div

C

LOAD

= 0.1µF

V

IN

= 5V

I

OUT

= -1mA TO -10mA

V

OUT

= 2.048V

-10mA

-1mA

V

OUT

AC-COUPLED
100mV/div

I

OUT

5mA/div

MAX6126_21

LOAD TRANSIENT

MAX6126 toc18

1ms/div

C

LOAD

= 10µF

V

IN

= 5V

I

OUT

= 0 TO 10mA

V

OUT

= 2.048V

0mA

10mA

V

OUT

AC-COUPLED
20mV/div

I

OUT

5mA/div

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

12 ______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VIN= 5V for MAX6126_21/25/30/41, VIN= 5.5V for MAX6126_50, C

LOAD

= 0.1µF, I

OUT

= 0, TA= +25°C, unless otherwise specified.)

(Note 5)

MAX6126_21

LOAD TRANSIENT

MAX6126 toc19

1ms/div

C

LOAD

= 10µF

V

IN

= 5V

I

OUT

= -100µA TO 1mA

V

OUT

= 2.048V

-100µA

+1mA

V

OUT

AC-COUPLED
10mV/div

I

OUT

500µA/div

MAX6126_21

LOAD TRANSIENT

MAX6126 toc20

400µs/div

C

LOAD

= 10µF

V

IN

= 5V

I

OUT

= -1mA TO -10mA

V

OUT

= 2.048V

-10mA

-1mA

V

OUT

AC-COUPLED
50mV/div

I

OUT

5mA/div

MAX6126_21

LINE TRANSIENT

MAX6126 toc21

2.7V

3.2V

V

OUT

AC-COUPLED
20mV/div

V

IN

200mV/div

20µs/div

V

OUT

= 2.048V C

LOAD

= 0.1µF

MAX6126_50

LINE TRANSIENT

MAX6126 toc22

5.2V

5.7V

V

OUT

AC-COUPLED
10mV/div

V

IN

200mV/div

400µs/div

V

IN

= 5.2V TO 5.7V

V

OUT

= 5V

C

LOAD

= 0.1µF

MAX6126_21

TURN-ON TRANSIENT

MAX6126 toc23

20µs/div

GND

5.5V

V

OUT

1V/div

V

IN

2V/div

C

LOAD

= 0.1µF

V

OUT

= 2.048V

MAX6126_50

TURN-ON TRANSIENT

MAX6126 toc24

GND

5.5V

V

OUT

2V/div

V

IN

2V/div

GND

200µs/div

C

LOAD

= 0.1µF

V

OUT

= 5V

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

______________________________________________________________________________________

13

Typical Operating Characteristics (continued)

(VIN= 5V for MAX6126_21/25/30/41, VIN= 5.5V for MAX6126_50, C

LOAD

= 0.1µF, I

OUT

= 0, TA= +25°C, unless otherwise specified.)

(Note 5)

MAX6126_21

TURN-ON TRANSIENT

MAX6126 toc25

GND

5.5V

V

OUT

1V/div

V

IN

2V/div

40µs/div

C

LOAD

= 10µF

V

OUT

= 2.048V

MAX6126_50

TURN-ON TRANSIENT

MAX6126 toc26

GND

5.5V

V

OUT

2V/div

V

IN

2V/div

GND

400µs/div

C

LOAD

= 10µF

V

OUT

= 5V

2.4994

2.4998

2.4996

2.5002

2.5000

2.5004

2.5006

0400200 600 800 1000

MAX6126B_25

LONG-TERM STABILITY vs. TIME (SO)

MAX6126 toc27

TIME (hr)

V

OUT

(V)

TWO TYPICAL PARTS
V

OUT

= 2.5V

2.5010

2.5005

2.5000

2.4995

2.4990
0 400200 600 800 1000

MAX6126B_25

LONG-TERM STABILITY vs. TIME (µMAX)

MAX6126 toc28

TIME (hr)

V

OUT

(V)

TWO TYPICAL PARTS
V

OUT

= 2.5V

4.9994

4.9998

4.9996

5.0002

5.0000

5.0004

5.0006

0 400200 600 800 1000

MAX6126B_50

LONG-TERM STABILITY vs. TIME (SO)

MAX6126 toc29

TIME (hr)

V

OUT

(V)

TWO TYPICAL PARTS
V

OUT

= 5V

5.0010

5.0005

5.0000

4.9995

4.9990
0 400200 600 800 1000

MAX6126B_50

LONG-TERM STABILITY vs. TIME (µMAX)

MAX6126 toc30

TIME (hr)

V

OUT

(V)

TWO TYPICAL PARTS
V

OUT

= 5V

Note 5: Many of the MAX6126

Typical Operating Characteristics

are extremely similar. The extremes of these characteristics are

found in the MAX6126_21 (2.048V output) and the MAX6126_50 (5.000V output). The

Typical Operating Characteristics

of
the remainder of the MAX6126 family typically lie between those two extremes and can be estimated based on their output
voltages.

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

14 ______________________________________________________________________________________

Detailed Description

Wideband Noise Reduction

To improve wideband noise and transient power-supply
noise, add a 0.1µF capacitor to NR (Figure 1). Larger
values do not improve noise appreciably. A 0.1µF NR
capacitor reduces the noise from 60nV/√Hz to
35nV/√Hz for the 2.048V output. Noise in the power-
supply input can affect output noise, but can be
reduced by adding an optional bypass capacitor
between IN and GND, as shown in the

Typical

Operating Circuit

.

Output Bypassing

The MAX6126 requires an output capacitor between

0.1µF and 10µF. Locate the output capacitor as close
to OUTF as possible. For applications driving switching
capacitive loads or rapidly changing load currents, it is
advantageous to use a 10µF capacitor in parallel with a

0.1µF capacitor. Larger capacitor values reduce tran­sients on the reference output.

Supply Current

The quiescent supply current of the series-mode
MAX6126 family is typically 380µA and is virtually inde­pendent of the supply voltage, with only a 2µA/V (max)
variation with supply voltage.

When the supply voltage is below the minimum speci­fied input voltage during turn-on, the device can draw

up to 300µA beyond the nominal supply current. The
input voltage source must be capable of providing this
current to ensure reliable turn-on.

Thermal Hysteresis

Thermal hysteresis is the change of output voltage at
TA= +25°C before and after the device is cycled over
its entire operating temperature range. The typical ther­mal hysteresis value is 20ppm (SO package).

Turn-On Time

These devices typically turn on and settle to within

0.1% of their final value in 200µs to 2ms depending on
the device. The turn-on time can increase up to 4ms
with the device operating at the minimum dropout volt­age and the maximum load. A noise reduction capaci­tor of 0.1µF increases the turn-on time to 20ms.

Output Force and Sense

The MAX6126 provides independent connections for the
power-circuit output (OUTF) supplying current into a
load, and for the circuit input regulating the voltage
applied to that load (OUTS). This configuration allows for
the cancellation of the voltage drop on the lines connect­ing the MAX6126 and the load. When using the Kelvin
connection made possible by the independent current
and voltage connections, take the power connection to
the load from OUTF, and bring a line from OUTS to join
the line from OUTF, at the point where the voltage accu-

Pin Description

Figure 1. Noise-Reduction Capacitor

PIN NAME FUNCTION

Noise Reduction. Connect a 0.1µF

1NR

2 IN Positive Power-Supply Input

3 GND Ground

4 GNDS

5, 8 I.C.

6 OUTS Voltage Reference Sense Output

7 OUTF

capacitor to improve wideband noise.
Leave unconnected if not used (see
Figure 1).

Ground-Sense Connection. Connect to
ground connection at load.

Internally Connected. Do not connect

anything to these pins.

Voltage Reference Force Output. Short
OUTF to OUTS as close to the load as
possible. Bypass OUTF with a
capacitor (0.1µF to 10µF) to GND.

+ 200mV) TO 12.6V INPUT

(V

OUT

IN

MAX6126

*

NR

0.1µF*

GND

GNDS

*OPTIONAL.

OUTF

OUTS

REFERENCE
OUTPUT

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

______________________________________________________________________________________ 15

racy is needed. The MAX6126 has the same type of
Kelvin connection to cancel drops in the ground return
line. Connect the load to ground and bring a connection
from GNDS to exactly the same point.

Applications Information

Precision Current Source

Figure 2 shows a typical circuit providing a precision
current source. The OUTF output provides the bias cur­rent for the bipolar transistor. OUTS and GNDS sense
the voltage across the resistor and adjust the current
sourced by OUTF accordingly. For even higher preci­sion, use a MOSFET to eliminate base current errors.

High-Resolution DAC and Reference from

a Single Supply

Figure 3 shows a typical circuit providing the reference
for a high-resolution, 16-bit MAX541 D/A converter.

Temperature Coefficient vs. Operating

Temperature Range for a 1 LSB Maximum

Error

In a data converter application, the reference voltage of
the converter must stay within a certain limit to keep the
error in the data converter smaller than the resolution
limit through the operating temperature range. Figure 4
shows the maximum allowable reference voltage tem­perature coefficient to keep the conversion error to less
than 1 LSB, as a function of the operating temperature
range (T

MAX

- T

MIN

) with the converter resolution as a
parameter. The graph assumes the reference voltage
temperature coefficient as the only parameter affecting
accuracy.

In reality, the absolute static accuracy of a data con­verter is dependent on the combination of many para­meters such as integral nonlinearity, differential
nonlinearity, offset error, gain error, as well as voltage
reference changes.

Figure 2. Precision Current Source

Figure 3. 14-Bit High-Resolution DAC and Positive Reference
from a Single 3V Supply

IN

MAX6126

OUTF

OUTS

GND

MAX6126

GND

GNDS

3V SUPPLY

IN

OUTF

OUTS

GNDS

REF

I

SOURCE

R

V

OUT(NOMINAL)

V

DD

MAX541

DAC

GND

OUT

/ R = I

SOURCE

ANALOG
OUTPUT

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

16 ______________________________________________________________________________________

Figure 4. Temperature Coefficient vs. Operating Temperature Range for a 1 LSB Maximum Error

Chip Information

PROCESS: BiCMOS

NR

OUTF

*OPTIONAL.

*

OUTS

REFERENCE
OUTPUT

(V

OUT

+ 200mV) TO 12.6V INPUT

IN

GND

GNDS

*

MAX6126

LOAD

Typical Operating Circuit

10,000

1000

100

TEMPERATURE

COEFFICIENT

(ppm/°C)

10

1

0.1

0.01
110

OPERATING TEMPERATURE RANGE (T

MAX

- T

) (°C)

MIN

8 BIT

10 BIT

12 BIT

14 BIT

16 BIT

18 BIT

20 BIT

100

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,

Series Voltage Reference

______________________________________________________________________________________ 17

Ordering Information (continued)

Package Information

For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.

PACKAGE TYPE PACKAGE CODE OUTLINE NO.

LAND

PATTERN NO.

8 µMAX U8+1

21-0036

90-0092

8 SO S8+4

21-0041

90-0096

+

Denotes a lead(Pb)-free/RoHS-compliant package.

PART TEMP RANGE

MAX6126B21+ -40°C to +125°C 8 µMAX 2.048 0.1 7 6126B21
MAX6126AASA25+ -40°C to +125°C 8 SO 2.500 0.02 3 —
MAX6126BASA25+ -40°C to +125°C 8 SO 2.500 0.06 5 —
MAX6126A25+ -40°C to +125°C 8 µMAX 2.500 0.06 3 6126A25
MAX6126B25+ -40°C to +125°C 8 µMAX 2.500 0.1 7 6126B25
MAX6126A28+ -40°C to +125°C 8 µMAX 2.800 0.06 3 6126A28
MAX6126B28+ -40°C to +125°C 8 µMAX 2.800 0.1 7 6126B28
MAX6126AASA30+ -40°C to +125°C 8 SO 3.000 0.02 3 —
MAX6126BASA30+ -40°C to +125°C 8 SO 3.000 0.06 5 —
MAX6126A30+ -40°C to +125°C 8 µMAX 3.000 0.06 3 6126A30
MAX6126B30+ -40°C to +125°C 8 µMAX 3.000 0.1 7 6126B30
MAX6126AASA41+ -40°C to +125°C 8 SO 4.096 0.02 3 —
MAX6126BASA41+ -40°C to +125°C 8 SO 4.096 0.06 5 —
MAX6126A41+ -40°C to +125°C 8 µMAX 4.096 0.06 3 6126A41
MAX6126B41+ -40°C to +125°C 8 µMAX 4.096 0.1 7 6126B41
MAX6126AASA50+ -40°C to +125°C 8 SO 5.000 0.02 3 —
MAX6126BASA50+ -40°C to +125°C 8 SO 5.000 0.06 5 —
MAX6126A50+ -40°C to +125°C 8 µMAX 5.000 0.06 3 6126A50
MAX6126B50+ -40°C to +125°C 8 µMAX 5.000 0.1 7 6126B50

PIN­PACKAGE

OUTPUT

VOLTAGE

(V)

MAXIMUM INITIAL

ACCURACY (%)

MAXIMUM TEMPCO

(-40°C to +85°C)

(ppm/°C)

TOP

MARK

MAX6126

Ultra-High-Precision, Ultra-Low-Noise,
Series Voltage Reference

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

18

____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.

Revision History

REVISION

NUMBER

0 10/02 Initial release —

1 3/03 Remove “future product” and “contact factory” notes 1, 16

2 6/03 Add “A” grade devices 1, 16

3 12/03 Change µMAX part number 1, 16

4 7/04 Add top mark to Ordering Information 1, 16

5 12/10 Add 2.8V option, add lead-free options, update Package Information 1, 2, 4, 15, 16

REVISION

DATE

DESCRIPTION PAGES CHANGED